DIY 12V Generator Charger - 10 Demonstration and How to Build

Please skip to the 2nd half if you just want to see it running.
Link to purchase an appropriate engine for this project:
amzn.to/2KXWlnE
Part1 of the 10 part series showing the details of construction of the generator:
• DIY 12V Generator Char...
FTC Disclosure Statement:
As an Amazon Associate I earn from qualifying purchases. Some links may be affiliate links. I may get a commission if products are purchased using the links provided.
Video demonstration of the exhaust setup:
• Quiet that Generator w...
Battery bank details:
• 1000Ah Battery Bank Pa...
How to power your house with an inverter during a power outage:
• How to Power your Hous...
This is a detailed multi-part video series in which I build a gasoline powered 12 volt DC generator and battery charger. I cover the why's, how's and reasoning behind the decisions I make and include the mistakes I make along the way so that you can avoid making the same ones.
I do not have any special fabrication skills (and it shows) so this project is one that most anyone with enough time and motivation can successfully complete.
I cannot guarantee against unauthorized modifications of this information or improper use of this information. I assume no liability for property damage or injury incurred as a result of any of the information contained in this video. Be sure to read and follow all safety instructions for any equipment seen or implied in this video, and use safe practices when working with potentially dangerous equipment. No information contained in this video shall create any express or implied warranty or guarantee. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user.

[@fosterechalimbana2160]

We have used the kzbin.infoUgkxOTeIs0vv4_9B5hsmnLsk9r930uDQLu_Y for probably 30 hours with our camper and it’s been great! The noise level is really only noticeable when running the AC and other appliances like the microwave, hair dryer, or coffee pot. It’s not huge like other ones and it has wheels so even at 90lbs, I can move it!

[@thra5herxb12s]

A suicide lead. I swaped mine for an iec plug from an old kettle. Only slightly safer but it's the best way I could think of without hard wiring and using a changover switch. I use an antique engine to charge my battery bank using an 80 amp car alternator when there's not enough sun for my solar panels. I enjoy seeing other peoples setups and learning from them. Thanks for posting.

[@conn.6847]

Glad to see someone this set up. Planning to build one myself, but on 24v setup. Way cheaper than buying a generator, as well it takes less fuel. Great job. As to silent your setup you gotta make an enclosure to it and add some foam to insulate on the inside. Just leave some air vents, for the engine to cool down, and as your setup you may add a propeller for more efficiency.

[@knurlgnar24]

I actually did this on an inverter generator a few years ago. Quiet? sure. But I couldn't find a reasonable way to prevent it from running hot enough to reduce the life of the unit unacceptably. I would have needed an enclosure the size of a shed with a reasonably large powered fan - which would waste a good portion of the electricity. I determined that I was better off just adding a muffler for future applications.

[@knurlgnar24]

BTW I agree that a 24V setup would be better!

[@conn.6847]

Or change to a Diesel engine. These doesn’t gets as hot as gasoline and they are more fuel efficient, lower rpm and more torque.. Mont a car propeller on the engine shaft. That way you won’t use electricity to power that, and will be bade by the engine while running. Mechanic propeller, not electric.

[@jwwm2]

I'm not any kind of electrical wiz, but I do learn a little from each of your videos. I sure do wish I could have a battery setup like yours, but I don't have money for that.

[@ak-joe2038]

Ive also built, destroyed and rebuilt this same machine half a dozen times now...finally i have one that works without melting belts, rectifiers, regulators, coil windings and so on. Automotive alts are absolutely not the answer. They're not meant to charge deeply discharged battery banks because that requires continuous high load output. They just can't do it. Permanent magnet alternators with external, heavy duty rectifiers are the way to go. They dont load down the engine because they're not trying to reach any 'goal voltage'. They simply put out what you put into them. The resistance is fixed so your output is controlled by rpm. Fans are important though...for the engine, alternator and rectifier. I have a 24 volt bank and my generator, with a 1/1.5 rpm ratio puts out 1800 watts at full throttle and 350 watts at just above idle. Been running it this way for some time with no loss in power or visible stress on the belt and you can just hear the engine is running easier. Thermodyne makes the bests PMA's money can buy.....check them out.

[@knurlgnar24]

The alternator I use in this video works great. You need the right alternator and the one in this video can do 100% continuous duty without any problems. It is a simple 27si without any modifications.

[@ak-joe2038]

@@knurlgnar24 my house runs completely off grid year round in Wisconsin so i have to recharge often come November thu march. I used almost part for part what you built and yes it does work great but running full tanks of gas day after day through the bad winter weeks i ended up melting down 6 alts last winter trying to draw 80-100 amps charging a 1000Ah 12V bank. Got expensive. The new setup is so so much more efficient. I get roughly 3.5 kwh per gallon of gas because the output doesn't drop as voltage rises. Its actually less load on the engine/alt as voltage rises. Very happy with everything mechanically... next step is full automation tied to my charge controller with a gene start/stop function. Love your vids though bud.... learn a lot.

[@knurlgnar24]

@@ak-joe2038 Congrats on the off grid house! There must be some miscommunication between us as I don't fully understand what you are saying, I assume you switched from the car alternator to a PMA? Interestingly enough I have been tinkering with changing to a 48V battery setup and bought a PMA and charge controller for this setup to increase efficiency and output. I haven't set it up yet so while I have all the calculations and such done I can't say whether it will all work out. I'll check out Thermodyne

[@ak-joe2038]

@@knurlgnar24 at fisrt i was using a 10si 125 amp delco. Worked great but didnt last. After 6 of those i went to the thermodyne dual core 1212 pma and 300 amp rectifier. Very happy now.

[@knurlgnar24]

@@ak-joe2038 Good job! I don't know why those 10si alternators are so popular - the design just isn't very good on them. I was happy to find the 27si that stays cool even at constant full load. A PMA would add more efficiency. Sounds like a good setup you have. I bought a WindBlue alt (still in the box) and calculated all the curves for the battery/engine/alternator/charge controller on paper and it all pencils out but I mostly expect the alternator to not perform to spec. Any idea if WindBlue is any good?

[@Townsonbck]

nice setup! I am off the grid and have simular set up. during winter months I just let it run 24 hrs 7 days a week do to short days and not enough sun. Runs my whole house. I all so run a PMA with a 440 charge Controller instead of a alt. Works great. Nice setup again.

[@gatorsmith4428]

I like this, thanks. I have converted a self propelled push mower to a Gen. with a simular setup.. alternator ran off of belt drive for self propelled, to a 63 amp alt, charging two 1000w car batteries, that powers a 1000w inverter.i also use it to jump start cars,wheelers, motorcycles, even my camper anything. I've got $60.00 in my setup and it's paid for its self many times

[@MrMrWrench]

Great video. Love the technical details that you certainly spent a lot of effort researching. Great Help. Thanks.

[@brianc5592]

That series where you built this was one of your greatest hits. Though I can't really use anything like that here. I live in a condo so I have to think small and quiet.

[@knurlgnar24]

Even in my neighborhood it is difficult due to the small lot sizes. One of those inverter/generators from Honda/Yamaha or the like may be your best bet. They can be modified with additional custom exhaust features for more flexibility. They certainly won't be as silent as advertized (all small engines are loud regardless of what they claim) but they are about as good as you'll get within reason.

[@47alpha62]

Believe guys those batteries videos and this one was worthy watching for me ,imagine a sollar setup and thins charging method as backup for some like me it's gold 😄

[@JohnDoe-td2ug]

Thank you for your excellent research and taking the time to go in depth on the engineering. Ignore the low brow non STEM grasping cretins... Can you elaborate on the claw type couplings? I've read that the new urethane spiders can withstand up to 1100 RPM, would that make direct drive reliable? Also, where do you source your pulleys/woodruff keys, belts etc?

[@jerrymctee5996]

I saw a youtuber use an ordinary heater hose!

[@eddieallen8982]

You should look around for a busted generator that's for sale cheap to get the frame and gas tank and transfer everything to it. That way you will have a sturdy frame and a bigger gas tank. Or make a frame and get some gas tanks from used riding mowers.

[@schickmann]

Great explanation knulgar, regarding my cs130 alternator. Thank you. I have not yet loaded it to the peak for longer duration than 2 hours. Also, my smaller engine, 2hp, which i had on hand, is not capabile of fully driving this alternator at peak output. These two factors maybe why i havent experienced any short commings yet with the cs130. Also i am only charging a battery bank of 600ah (golf cart 6volt batteries series/parrall).

[@knurlgnar24]

With a 2hp engine I am sure that you'll continue to be just fine! That smaller engine isn't going to be capable of overworking the alternator so it's a non-issue I would think.. With the benefit that CS130s are so common they practically give lightly used ones away at salvage yards.

[@MrSnapy1]

Nice work! My dad had something like this to charge boat batteries. Which you could add another belt and pump water out of the well. While not the best water pressure when the power went off we had water.

[@dota9925]

Haven't yet watched the build videos, and certainly not read all the comments, but it occurs to me that if you're driving the alternator 1:1, why not direct drive the alternator and nix the belt altogether? Also, would it be worth considering a voltage sensing capable alternator (like Chevy CS series) to offset voltage drop (though with the voltage reading at your bank, you probably already are?). Now off to watch your build vids! :)

[@Townsonbck]

Love it. Nice job. I've done the same thing. Works great. Thanks for sharing. You still use it today? I see the video is 7 years old.

[@knurlgnar24]

Still have it, still works. I generally use a standard generator and an industrial battery charger now instead. Fun project though and this simple system is infinitely repairable unlike my more complex setup today.

[@narcissistinjurygiver2932]

have you considered getting a slow speed diesel like an old Lister diesel and use that to power your system

[@SprucePlywood]

About 10% loss for belt setup. Why not mount alternator straight on output shaft, as you are running 1 to 1 anyway?

[@jangofet3756]

SprucePlywood he ran this with a love joy coupler and the rubber spider in the coupler didn't like it.

[@billclinton2255]

Hypro adapter.

[@Coolkeys2009]

First!, You made us wait for that I'm sure I watched the other 9 videos 2 yeas ago waiting for you to start the engine :-) Can you briefly mention the safety precautions you take to avoid back feeding and inverter destruction?

[@knurlgnar24]

Coolkeys2009 I have a few videos out there on safely connecting to the house. One is how NOT to connect an inverter to your house and the other covers the many safety issues with this 'backfeed' technique.

[@jetstreamblueZ06]

***** wonderfully informative videos, for those that stumble on this channel can you please mention how important it is to disconnect the house from the grid before operation if you are going to backfeed your house with a secondary voltage, for the safety of utility workers. You can't mention it enough, a simple lockout on the main breakers would suffice. Keep up the good work Knurlgnar24 knowledge is power.

[@danyala.1659]

***** Your videos are awesome! They cover every category I can think of, for the most part. Although, I have to ask you, why a alternator over a dc motor?

[@knurlgnar24]

Danyal Ahmad DC motors that can be used as generators use brushes which are unreliable. Alternators use slip rings which can run for thousands of hours without service. In addition, they are more common and much less expensive for a similar build quality. Alternators are mass produced, field tested for millions of hours in various equipment, and readily available. Most brushed DC motors can only operate for a few hundred hours at full load before failure while alternators run for a few thousand.

[@danyala.1659]

***** Alternators produce AC electricity, and must be run at a extremely high rpm to get a good 120v out of them. However a DC motor obviously produces DC electricity, and is very easy to get power out of. I can actually spin them with my hand and get a easy 12v out of them. I have tried using several used Treadmill motors, from ebay for only about $50 each. Where has I have purchased busted up Alternators from the junk yard for the same price. Also, Alternators need some input to start generating. I would guess that that there is a difference in current between the two. You are right about how long they survive, for the most part. I think a DC motor running 24/7 will survive about 4 years. Its hard to say how long a alternator will survive, in the best scenario possible they'll run 100,000 miles. I'm just trying to say there's cons on both side! How much output do you get from it? I'm pretty sure you can get real good results with a 6 horse power engine. And this is all based off of me using a Professional Series electric drill which wasn't ever close to 1/2 horsepower. Have fun experimenting, that's all I can say. Please tell me if I have made any mistakes.

[@2299jsimon]

Didn't see where anyone mentioned the venting of he hydrogen gas... if you drain your batteries down, charging will generate quite a bit... nice job.

[@DormantIdeasNIQ]

Keeping the belt tension-free when not in use, and having to use the lever each time... hmmm! I would install an infinite screw mechanism with a lock nut lever and small crank. ...and if you want to go smack as perfect as you tend to do on everything you deal with, a tensometer can be attached in parallel(so can be unlatched) so that you only tension the exact amount each time. (easy with the infinite screw crank device) Or a cantilevered that locks on a lock pinion spring-loaded pin. A big oil filter like wrench that grabs the alternator full-body and centered may be the easy solution. ...and to quiet down the whole thing, besides the sound proof box I mentioned on the other video, put this thing on 4 spring legs! you will be amazed at the smoothness gained!

[@patb9375]

He said he did not have that stuff laying around so he did not do that.

[@Langsta1000]

You Rock knurlgnar! I had the chance to drive all over creation last night to get a free 4 cycle weedwhacker (for a similar DIY generator... but smaller) !! but I fell asleep. (stupidstupidstupid) (troy bilt) prolly not the best quality! id better follow your lead and save up for a Subaru Robin or some such!!! keep up the good work! my whole idea is to perhaps have a motorized-bicycle, mini generator, and WHO KNOWS WHAT ELSE!!! built around one easily swappable engine! then just acquire a few identical engine units, learn to service them to the bone, and always have at least two up and running at any given moment! (this is sort of like an 'ultimate road trip accessory' type thing rather than an 'off the grid home' type of thing, but similar tech and yeah I need to get my butt in gear!!! one critique! not sure if you have dogs or cats or small children around ever, but I would add some safety features on there (at a minimum and enclosure for the pulley system!) I think one of the most important parts of DIY is helping to shepherd people towards safety oriented design. build it so that anyone could safely use it and laminate an 'instruction page' and staple it on there! that way when you have two broken legs and your neighbor has 1.5 broken legs and the power is out and its 28 below you can be like, "Hey buddy, I don't think I can make it, Can you crawl down to the garage and start up the emergency generator so we can run the space heater." "its safe to operate and the instructions are posted on the side, here take my headlamp, and if youre not back in 15 minutes ill try to call for help" yep

[@ananayakandpal9491]

Thanks for sharing with us. Thank you.

[@austin30233]

Are you running your house almost exclusively on your generator setup? It seems like thats what you implied in the annotations @17:43

[@knurlgnar24]

austin30233 I can use this to power my whole house and have done so, but I use use the normal electric utility like everyone else most of the time. (is that what you mean?) Everything works just like it normally would on this setup except that I am more careful about my energy use, and nothing that requires 240V operates. I have kerosene for heat and a portable propane stove for heating water. (I can also use the microwave oven for cooking)

[@JeffsTravels]

Excellent video. You must be an engineer in real life.

[@scaniawahl]

Is the generator strong enough to run a fan? So you could mount it in a box and drop it over the generator😊 would help some against the soundwaves 😊

[@mobitronicsolarmobitronics6052]

Merry Christmas and a happy new year. Xxx Charles Rotterdam Nederland.... --

[@nhhbbyloggr5022]

Knurlgnar, I've enjoyed the videos focusing on the Battery Bank / Inverter system. They were the motivating factors which led me to the Samlex 3000 which you spoke so highly of. I did call the factory and the US rep for these particular Inverters and they were responsive, informative and a great help for our particular application. Currently we are running 8- 12 volt deep cycle with a 774 Ah total rating, Your # 10 video shows a new duel 20 amp outlet , pigtailed to a 220 Volt drier plug. I understand the connections ( not show ) for the L-1 - L2 connections but how did you wire the neutral in the duel outlet plug.? I assuming you had to tie them together , sharing the neutral from each neutral from the Inverter to share as a common neutral at the point of connection to the drier receptacle. " Assuming " usually gets me in trouble so would you please clarify how you dealt with the neutral as it could affect the ground fault circuit of the Inverter. NH Hbbyloggr

[@knurlgnar24]

You are exactly correct. The neutral was shared between the two outlets and the 'hot' was connected to the corresponding hot phases. It would be best to test this setup with an ordinary 120V load on each phase to ensure it is all connected properly before using it with an inverter. As always, be aware of any safety issues.

[@nhhbbyloggr5022]

***** Thanks for clarifying. Also because of the conflict with the GFI you do not connect the GROUND ? I see there is a separate grounding lug on the rear of the set. Do you use that at all to " bond" to the house ground? Thanks for your help. NH Hbbyloggr

[@knurlgnar24]

NH Hbbyloggr I actually didn't connect the GND to the inverter in this case to avoid GFI issues. The grounding lug is a no-connect internally in the inverter and is only there so that you can guarantee the inverter case is electrically grounded. It's required to be there per UL spec but isn't really necessary even for safety except for specialized applications.

[@nhhbbyloggr5022]

***** Thank you. That ties up the loose ends and now I can eliminate possible " oh crap " moments. Happy New Year !

[@michaelmahney4698]

I don't understand saying no ground ok or 2 grounds both wrong dangerous.

[@codymiller4909]

Where does the momentary switch hook too?

[@X02switchblades]

can you use this for a range extender in an electric car? In a system with two battery packs, when one of them is almost depleted, the electric motor switches to the fully charged and then if you want you can switch on the "range extender" to charge the depleted one. Can you charge a battery and run a motor at the same time so you have one battery pack?

[@tiorobot]

Thanks for posting. I enjoyed watching your videos and learned some things alone the way. I built a 12v power plant like this once but I think the motor was too small. It would start and run just fine then bog down and stall. I wanted it for running spotlights to do some night fishing in Arroyo City, Tx. If someone wanted to build a "portable air conditioner" how big of a motor do you think it would take? In other words, a gas or diesel powered, stand alone system such as yours, but for cooling air instead of charging batteries. I drive a truck "over the road" and have to comply with idle laws in certain cities and states. Some things I prefer to build myself from scratch.

[@JohnSmith-ug5ci]

So here s my question. When charging the battery bank how do you achieve a balanced charge on all those batteries with them hooked up like that or is it not an issue? Thanks.

[@occlcll48]

I read the avg home uses 920KW of energy. This set up was shown to work with 5kw. How many kw does this set up support. Also how much was all this.

[@acet7]

Nice set up

[@rexhorning7228]

I can get a lot of I formation from a running engine. Is it laboring, freewheeling or missing out sort of stuff. Some decision’s are made by what the equipment is telling you not just the math.

[@knurlgnar24]

If you do your math right the equipment will tell you you got it right. If you get your math wrong the equipment will be very willing to call you on your errors!

[@keithparent8970]

All this talk about amps and watts and volts gets a little confusing. "I am sorry but it is what it is." So my question to you if you can answer is: can your 12v set up provide me with 1200 to 1300 watts that I think I would need to run my pellet stove and fridge and a few lights during a power outage, any extra would recharge the batteries? Thank you in advance for your assistance and answer. ....... Keith

[@knurlgnar24]

This setup will provide about 1kw. If you need 1200 or 1300watts that's OK as long as you have a battery or two connected and you allow the battery to recharge between use, as you will be pulling 200 or 300 watts out of the battery. (e.g. a refrigerator won't run 100% of the time) You can get higher output alternators but the 12V ones that can truly provide continuous power in an applcation like this are uncommon and expensive (think busses, semis, etc) and you would need a larger hp engine. At that point you're probably better off with a gen set. This setup uses an extremely common and cheap alternator and an engine you can buy for $100 at harbor freight with a coupon making repair parts extremely cheap and easy to get for decades here on. This wood base lasted for many tens of hours so far and still works just fine but it certainly isn't ideal - just commenting to note that I realize this fact. It does show that one doesn't need metal fab skills to build a good working setup though.

[@koningbolo4700]

I have two similar batteries which I like to use in my van to power a small fridge and some other low powered appliances. I plan to use a charging relay which will switch the two batteries parallel to the existing car (starter) battery if that one has reached full charge. I have heard I have to modify the alternator to output less voltage (then the standard 14.4 V) by having a diode in series with the sensing wire to the alternator, which should make the alternator put out about 13.7 V - since a diode takes about 0.7 V away from the sensing voltage thus preventing the field coils reaching the standard voltage. This is supposedly needed to prevent overloading the batteries. May batteries are Northstar NSB 100FT (RED) which float charges at 13.6 V and boost charges at 14.1 V. Are your batteries different or did my source err too much on the side of caution??

[@CHARLES12STRING]

always wanted to build one - I have my motor picked out and now I'm glad I found your videos for tips on build - but then I run into build cost - why are the pre-built so much cheaper ? generac inverter generator is $600 and you cant find a pure sine 2000 watt for that -

[@CHARLES12STRING]

www.northerntool.com/shop/tools/product_200402909_200402909 as I understand this is pure sine wave also correct ?

[@CHARLES12STRING]

CHARLES12STRING 208 cc was the engine I had picked out with a cast iron sleave www.northerntool.com/shop/tools/product_200638383_200638383 but I thought that I would have to guess at the pully size , so the 1 to 1 at 5 inch pully sounds great- I had planed to use a gm one wire set up but now you have changed my mind on that also-

[@knurlgnar24]

CHARLES12STRING Yes, the inverter you linked to is pure sine. It is about an 1800W inverter with only a 2000W (actual) surge so take that into account. A 2kw inverter will be more capable in reality.

[@knurlgnar24]

CHARLES12STRING That's a great deal on that engine. I wouldn't hesitate to purchase one for your project! It isn't going to be ultra reliable like a Honda GX or a Briggs Vanguard but small engine technology is pretty well stable now so even the cheap ones do it pretty well excluding manufacturing defects. That engine would be a great starting point for this project.

[@knurlgnar24]

The pre-built ones will always be cheaper, but keep in mind that they need to run 24/7 to give you continuous power. If you have a battery bank then there is advantage to the alternator-inverter setup. For most people just purchasing an inverter-generator is the most practical solution. For those who have aspirations for solar, renewable energy, or silent night operation the separate inverter/alternator setup is a good alternative. My setup is designed for a reliable 2000 hour operating life which is better than one can expect from the Generac style inverters, and closer to what you would expect from the Honda inverter generators.

[@w4nio]

Thank you knurlgnar for all the videos on the 12vdc generator. I cant imagine all the hours and money you put into this project. I bought a Predator motor yesterday and need to order the parts. Would you please give me the part number of the 5 inch pulley form Jegs. Is the Kevlar belt used for the two 5 inch pulleys 4 L 36 inch? The alternator is a 27si OEM? Thank again !

[@GeorgeOu]

If it's 1:1 transmission ratio, why can't you directly couple the output shaft to the alternator?

[@knurlgnar24]

1st, standard engine rotation turns the alternator backwards. You can get a modified or non-directional fan to mostly fix this (the brushes are not in an ideal arrangement but it will work). 2nd I tried that in this video series and the spider coupling blew apart. Alignment needs to be nearly perfect and a coupling rated for reciprocating loads must be used. I found a belt to be easier to build and maintain long term.

[@GeorgeOu]

@@knurlgnar24 Fair enough, thanks.

[@mmccann9850]

I watched most of these and read a lot of the comments and maybe I missed it, but did you do this at all for cost savings reasons? Obviously you like to tinker, learn and DIY and I think that is awesome, but at the end of the day, would Joe Sixpack who might not have ever swapped an alternator in a car, or know the difference between a neoprene vs kevlar belt find any financial advantages to this setup vs. picking up a prebuilt generator?

[@patb9375]

He is charging his batteries if the solar does not keep up, a prebuilt generator would produce power at 120v ac so what then plug a battery charger into that? and Joe sixpack would know how to swap an alternator. People don't listen.

[@v.khelawan6162]

hey i have and idea why dont y have 2 alternator and connect it in parallel . and use tye engine to run both of them

[@jimwade5712]

Have 10 motors 20 gen....than you can power the house..

[@lukerediger8431]

I've just started building my own, I watched the series years ago and the algorithms for the internet must have cross referenced my recent orders with previous youtube viewing and put this on my youtube home page. I've found L-095 jaw coupler that should handle the load so I intend to avoid belts, if you're still around, would you comment on your generator's current status, is it still working, any pit falls to look for?

[@knurlgnar24]

Still working though I admit I haven't actually used it in a couple of years and I had plans to convert it to a 48V setup with an external regulator mod or a PMA which I also purchased. Two more video ideas that I never did... Anyway if you use that jaw coupler make sure the spider and couplers are rated for a reciprocating load or it will tear itself apart after a short time, and alignment is critical. More than a couple degrees out of alignment and service life will be short. Those spiders don't like vibration and will not last as long as a belt which is also more easily replaceable. I do like the coupler setup better overall though for other reasons. Oh, and be sure to pay attention to cooling fan rotation direction if it is directional on your alternator.

[@lukerediger8431]

Thanks for the feed back! I intend to build a cage out of angle iron to house the setup, and use threaded rod adjustments on the alternator mount so I can fine tune the alignment one 3 axis. I winced when was re watching the video where you talked about jaw couplers not being great for reciprocating loads right after I paid 90 bucks ordering them :D We'll see how it handles it. I was considering adding a hefty fly wheel to the engine to reduce the impulses on the coupler... I may end up just using a belt I guess. I ordered a urethane spider, we'll see how it works compared to rubber. I'm going to use a 10ohm 100w potentiometer/rehostat on the field windings, I was watching another guy (kzbin.info/www/bejne/fYaup3p8mb6olbs) who built one and it seems that if the battery is low or a sudden large load comes online, the alternator can't keep up. He uses one to limit the current so that the batteries take the load spike rather than stall out the engine. I suspect this isn't an issue for you since your battery bank is massive comparatively, as well as the length of the leads between your generator and the bank provide current limiting so it's not an issue. Since I'm starting out with just a single 95AH Deep cycle, I'm worried about charging too fast and want to be able to limit the current as well to ensure I don't boil them. He also uses an external regulator from chemlec (chemelec.com/Projects/Alternator/Alternator-Reg.htm) which I'm going to build as well. My alternator is supposed to be a 3 wire but I got sent a 1 wire, so I might as well just jump right into it. I'm going to make a youtube project out of it, I don't think I'll try to become a tuber, but I'll make the video's public as a knowledge repository. I'll send you the links when I get started, though I'm picking away at it slowly right now and I'm still working (from home) so I don't have as much free time as I thought I was going to get. Thanks for keeping your channel alive, I think it was you that I talked about fixing an 800 watt ProWatt years ago? had a bad switch, still going strong. That and a 1000W pure sine inverter are what I'm going to use on my setup. Eventually I intend to automate it with a micro controller to make it work like a storebought inverter/generator that auto starts to top up the battery bank, but I'll be happy to just be able to keep a charge and runs some stuff first in the short term. Sorry to figuratively talk your ear off. Cheers!

[@TruckinBeagle]

Don't let your insurance see this video! 🔥

[@knurlgnar24]

It's not a permanent install and so not against any codes. Not an issue.

[@frar.841]

Hi, How do u know when the batteries are fully charged and stop the alternator from overcharge them and/or damage them? Also, when u connect the plug from your inverter to your house, do you turn off the main power switch on the panel?

[@victorystonephotography8211]

The alternator will not overcharge the batteries, it has a charge controller built in

[@sitealive]

Could you tell me what all would I have to get and do, to make an electrical engine with a altinator? Also to have it recharge the battery at the same time?

[@jamiemcmann8748]

that makes zero sense

[@mitchelljustus5154]

love the setup but where u have the wire going threw the wall threw insulation i would put conduit or pipe and have the wires go threw that for fire safety sakes i know u have fuses and such but i had a house fire and now i check and account for every stupid small things

[@patb9375]

It is 12 volt dc you could put you tongue on it, might tickle.

[@ThatGuyKappa]

you should modify the governor to run at optimal rpms in all load conditions.

[@patb9375]

He said he didn't want to do that.

[@Loopyengineeringco]

Hey knurlgnar. Your build insipired me to build a similar system! It's running but my supposedly as-new 22SI is putting out 17v! + goes to battery +. Gnd goes to gnd/battery -. One of the twin spades goes to +. I and R unconnected. Does the wiring sound right to you? Maybe it's needing a load on the 2nd spade connector (simulated bulb)? The 2 spades are electrically connected. Edit: without the battery as load, it's at 18.5v!

[@koollee]

he knows more than I, but it sounds like youre spinning too fast. --- u posted months ago.. please tell us how U turned out with yours. Thanks

[@Loopyengineeringco]

It turned out that one of the field winding wires on the rotor were shorting to ground, because of a careless rebuild! (I bought the alternator on ebay as 'reconditioned'). So it was always running full power, because the other end of the field winding was full 13v. It works perfectly now. I'll do a video soon. Thanks for replying

[@RelentlessLegacy2020]

can you make a video explaining how to wire up that 240 wire you showed

[@patb9375]

don't use piggy backed plugs if you forget to trip the main breaker you are feeding out to the main power line and can kill or hurt a lineman working on the power line. there are device to switch you for $50 on ebay.

[@richardwatts2294]

Stay with the first hose,then five gal.bucket with water in it.coil the hose inside.no sound,no smog.if a fire breaks out you have water.

[@knurlgnar24]

That's a good idea which is obvious in hindsight but not a common approach - water muffles very well.

[@knartfocker_]

Could you grill a panini on that muffler?? Would be an added feature.

[@KSfixitman]

Love your videos. I have sort of the same set up. Same size motor but knock off make. Alternator was planned for a wind turbine so it has been changed to magnetic rotor with the rare earth magnets. I had the same problem with the pulleys and ended up with a close set up to what you have. Question off this subject. Have you dealt with grid tie inverters much? Why I ask is I have a 300 watt one that I wondered if there was a way to make it in to a regular inverter since its already pure sine wave.

[@knurlgnar24]

KSfixitman Interesting that you ended up with a similar setup! I have not worked with grid tie inverters much, but I doubt you can 'convert' one into a stand alone inverter if it is not designed to be one. The inexpensive ones generally rely on the grid waveform to operate and augment the crests with additional voltage to shove some power backward into the lines and they don't really have the smarts or components to operate as a proper stand-alone inverter.

[@KSfixitman]

That makes a lot of sense. I was kind of thinking it would not be possible but I thought Id ask. Thanks for the response.

[@tommyb.6064]

Your cable length and voltage drop should be really huge, limiting the charge speed of your batteries. I have a camper van with a 80 amp alternator and every cable under the hood had been doubled, ground from the alternator chassis to the body (1ft 4awg) and battery to alternator with a( 2x 4awg). My battery bank consisting of 6 large truck bateries are located at the back, i had to run (3x 4awg) calbes, in order to keep the voltage drop from the front to the back below 0.5v when the batteries are at 25% of charge and the engine rev at cruise speed. I instaled a bridge amp meter close to the alternator and having only one 4awg was limiting my charge current to about 30 amp... i was haiving 14.5 at front and 13.xx at the back sometimes.. now the needle peak up all the time at least to 75 amp. And on your setup you have double the cable length since you are not using the body as the ground conductor... One thing that can be done to acomodate long cable... well sort of a thing.. is to use an externally regulated alternator and set the regulator voltage probe at the battery bank instead at the alternator contact. The voltage will push the alternator voltage to compensate the voltage drop.. well, the most the alternator can do it. but keeping your alternator voltage as low as you can by reducing cable length and increasing like HELL the cable size will keep the whole system more efficient. For those who wonder why i used 3x 4 awg cable.. well, first that's what i had, second, it was a great deal, and tersio, it was easier to manage that one big and stiff double zero gauge cable.

[@patb9375]

He was using triple ought (3zero) and his drop would be nothing at 30 feet total. The body on your vehicle may be your problem. You should run one of those wires on the negative side it will probably help you. He said he is running it at about 70% and it charges his batteries quickly, so he did well. When ever you think you need an extra cable for your vehicle run both positive and negative same size it will be more efficient.

[@norcal8718]

Awesome video very informative. What do you think of a set up with a battery and alternator and an electric motor no need for a gas engine or diesel engine? Alternator powers the battery the battery powers the motor and bam you have electricity. What are your thoughts? Thank you so much 💡

[@patb9375]

He would need you to stick your thumb on the pulley to hold the belt

[@KevinCoop1]

Wow, you just came up with a free energy device. Seriously, it will not work.

[@norcal8718]

@@KevinCoop1 Why not? Think about it, rotating movement of the right materials creates electricity so why can't it come full circle?? I know it sounds too easy and if it works why isn't it already being done blah blah blah, I know I get it. I'm going to set it up you never know unless you try it right 👍🏼

[@KevinCoop1]

NorCal Ok, lets think about this for a minute please. A battery is charged by utility power and runs a dc motor. The motor has loses of energy, as is apparent in that under a load, it produces heat. The motor is coupled to a alternator that produces voltage and also produces heat or losses. The alternator provides power to charge the battery. So it will work as long as the energy stored in the battery will last and then stop working. Now connect a load to it like in the video. Now your system will work until the previous losses plus the new load deplete the energy from the battery. To make this system work longer, tags out the motor and the alternator, and you will only have the load draining the battery. I hope this helps make sense of what you were wanting to do.

[@allthingsmowing]

Jesus, 13:10 to hear it run and operate of that's what you came for. WAY over 10 minutes of flapping gums to get to what we all waited for. There ya go

[@stevejones1777]

UR ONE VERY CLEVER MAN TY

[@terrytytula]

I'm looking for a generator for a VAT's ( vertical axis wind turbine) your pulley and belt system look's ideal. Your thought's?

[@victorystonephotography8211]

a treadmill motor is better for wind turbines, alternators wont get the RPM needed to generate enough power

[@iamamo2min595]

Nice video, I have a question what's the best pure sine wave inverter 500w ( decent price ), ? I intend to run my laptop (120w no Battery) and 2x 15w fans off the solar system. thanks for help ...

[@knurlgnar24]

You probably don't need pure sine for your applications, however the Tiger Claw 1500W inverter may be a good choice if you want the flexibility.

[@dano4572]

very good. thankyou!

[@gardentechniciantom4845]

How did you connect the hour meater to the engine.

[@knurlgnar24]

These type of meters simply wrap around the spark plug wire to get their signal. Wrap it 10 times or so to ensure you get a solid signal. Many of the negative reviews you see from this type of item are from people who don't properly install them - they work great!

[@jonnycrackles8026]

how much did you spend overall?

[@gelumiro1160]

dear friend I could send the assembly diagram inside the MPPT Solar Charge Controller EP eTracer 60A 12/24/36 / 48V, or at least one can of photos inside, because I do not remember where you connect the bridge rectifier thank you very much

[@richsavala7390]

Don't understand going to the large pull on the alt. you are losing amps. with that set up because you are one to one with the motor. I've made a set up for boondock camping with a 5.5 hp. Honda lawn mower motor with 5 inch pull on motor and 2 1/4 inch alt. which is GM rated at 105 amps. I can run engine at a little above idle with 14.4 volt's and 70 to 105 amps depended on load and battery charge on low sun days I may need to run 1 to 1 1/2 hours to top off charge.

[@mitchelljustus5154]

oh and backfeeding is dangerous just it the rightway to panel and get a disconnect

[@sjlouvieify]

thanks in advance!

[@martinonumero]

Good day, what inverter do you use on this project ?

[@patb9375]

watch the video

[@arthurstacey2730]

for $63.50 I got a NEW CHROME BBC SBC CHEVY ALTERNATOR 110 AMP 1 WIRE HO ALT. easy to wire up ,, with it being a 110 amp it charges battery bank fast

[@donboehner6005]

Thanks.

[@blandman3471]

I like your setup, but I think it would be safer in a shed or doghouse.

[@benmudn]

What is the gas tank capacity?

[@knurlgnar24]

Ben Bat just shy of 1 gallon

[@cloroxbleach1200]

0:52 "Backup heat" Is that the waste 'heat' from this generator? :D

[@patb9375]

Wood stove

[@josephpenley4283]

FORGET ABOUT THE SOLAR PANEL. SOLAR IS OUT. RETURN THE ALTERNATOR. GO OUT JERK THE ALTERNATOR OFF THAT BROKE DOWN CAR IN THE YARD. IF NOT WHAT THE PROBLEM IS. TEAR THE GUTS OUT OF IT. MOUNT TO VANGUARD MOTOR. TAKE THE AC OUTPUT U GETTING OUT OF IT. PUT A RECEPTACLE ON IT. PLUG IN EXTENSION CORD. GO OVER THERE GRAB THAT BATTERY CHARGER PLUG IT IN TO BATTERIES IN THE BASEMENT.

[@wilipno]

Anybody know what ever happened to knurlgnar24? He hasn't had any videos in a few years!

[@cptbricky]

R I P

[@shanegrangrad8559]

Motor oil in these little engines needs to be hi zinc oil . Run in motor oil is very good as its hi in additives tgat these small engines need to get long life . Normal car engine oil is ok but not optimum . A purpose made motor cycle oil for engines without filters or pumps ( splash feed oil ) is best . But very expensive . $40 per litre average price . Chain drive is best less drag to the driven equipment .

[@karltaylor7378]

Would have been cheeper to just buy a diesel site generator

[@JodBronson]

YES !!! Don't knock on my homies with poor Mathematics! LMFAO :D

[@flitsies]

It's good that you can make this stuff but at the price of generators it seems a lot of time and money when you can buy one that will do exactly the same thing for less, I don't mean this as a criticism. I bought a fantastic 3.5kw inverter generator for less than £500 it was fully oiled up and ready to use all for that price the only thing I needed to do was put petrol in, and it was electric start so you just turn the key no need to pull the string even though its there. You can buy these generators on ebay, they come with digital panel displaying a multitude of information, and they have safety features built in and they are very quiet. So I wonder why you would build something like this when you could buy one ready to go probably cheaper? Are generators very expensive where you are?

[@flitsies]

***** Here's one not overly expensive little bit smaller than my one but still pretty useful. www.ebay.com/itm/SUPER-SILENT-2200W-PORTABLE-SUITCASE-INVERTER-GENERATOR-GG-2000-Si-/221469513188?pt=LH_DefaultDomain_3&hash=item33909c95e4 Here's another similar to my own one but my one has 3.5kw. www.ebay.com/itm/EPS-Inverter-Generator-/191534608213?hash=item2c985a2f55&vxp=mtr Anyway just have a look through ebay you can find some good one's at reasonable prices. These are on the USA ebay. If you want it to run computers and things like that it will need to have an inverter but you can use an ordinary generator and plug an external inverter into the 12 outlet so long as it has one of course.

[@patb9375]

you did not listen at all to what he is doing. watch the video again and listen this time. if he wanted a generator producing house voltage he could build it, that is not what he did.

[@deathincarnatesplace]

you could do the same with an ebike motor

[@davidjones1393]

NICE

[@theoldwizard998]

I am 100% with xboxer1985 ! While I know that you are an intelligent person and understand the risk and how to mitigate them using a "suicide cord", Unfortunately there are too many people in this world who aren't very smart and will NOT heed your warnings. The potential is an unsuspecting utility workers getting ZAPPED !

[@patb9375]

It is not a suicide plug it is more likely to hurt the linemen fixing the outside plant than the homeowner. That is why it is illegal, is when you don't disconnect from line you feed back and can hurt a lineman. Calling it a suicide plug makes people think well I won't make that mistake so I will be ok, but if they kill someone they will not be ok.

[@rjakiel73]

So you bought a $300 engine and $120 alternator and custom racing pulley. Then had to go through the whole fabrication process. OR you could have spent the same amount on a new 4750 watt surge / 3750 watt continuous dual fuel generator with factory warranty.

[@knurlgnar24]

I think you're missing the point of this whole project. If you want a generator then buy a generator, yes I agree with that.

[@REVIEW_JUJUR]

A 2stroke 1000w gator generator is very cheap. Less than $100. I cant imagine how much that batteries & inverter cost...

[@jasonfelci3672]

The batteries he got for almost nothing

[@SandraSantos-rp6yl]

Since the ratio is one to one, you could make a more compact unit by mating the alt to the engine through a male and female spline shaft

[@BOREDANDWELLBORED]

Can you explain what you mean?

[@billclinton2255]

Hypro adapter

[@bmw328igearhead]

You never want to direct drive an alternator. The pulses of power from the engine don't play well with the bearings in the alternator. Its best to have a belt, or rubber coupler between the engine and alternator, it dampens the spikes considerably. Things last longer, everybody happy. Unless you use a large flywheel. The mass itself is used to absorb the pulses, and if a large enough wheel is used, it becomes a mechanical battery. Storing and releasing energy as supplied and demanded. (Edit: consider this, using an RPM based on-off switch, to control the alternators rotor windings. Flywheel slows down below limit, cut power to alternator, Flywheel speeds up, then once above speed set, turn back on the rotor windings. Balance is achieved with minimal issue. Or use a bigger engine. 20hp for every 100amp worth of alternator) But hey... that's just my take on your question. May peace be upon you, in all facets of life. Stay safe out there.

[@Tanks-Link]

I had something like this set up but hatted all the noise extra wiring so I had an idea I bought a wrecked motorcycle had the stator rewound to a 200 watt stator and hooked it up to my batteries. works great electric starter etc. and runs very quite FYI I did hook up a 14"12V fan to the radiator. cost $150 for bike, $30 for fan at wrecking yard, $100 to rewind stator so for under $300 awesome charging system

[@stevejones1777]

CAN U DO A VIDEO of YOUR SET UP? TY

[@TheBigdawg0614]

late to the party, but thoroughly enjoy your videos. was curious aside from time, effort, and the batteries, how much did you have to invest in your little setup. I am working my way through a similar setup, but with solar as my primary battery charger. have been trying to figure out what I can do for a secondary/back up charger. this looks great, as well as looks to be semi portable from a emergency sense. love any input. will definitely be spending a lot of time catching up on your other videos

[@wire54321]

13:08 R.I.P. Headphones wearers

[@glasstronic]

I'd do it differently, but I very much enjoyed watching this. Well done! It does what you built it for. Thanks for posting!

[@KuntalGhosh]

connect the voltage scence line of the aultarnator to the battery not in the the out put of the aultarnator because there is a line voltage drop and to prevent voltage drop many aultarnator have scence line and i can see that the alutarnator that you used in this video also has one and you have connected it to the out of the aultarnator.... if you put the scene line on the battery then it will maintain 14.4v on the battery but put more load and higher voltage on the out put post of the aultarnator...

[@ericdrisgula3879]

I dont understand a few things , first of the exhaust, why didn't you just buy one of those $7 universal tube style small engine mufflers and attatch some simple 1 inch diameter flex line or even pvc type tube for an exhaust it'd have been cheaper and more correct for the engine giving you proper back pressure . Second your in the end doing all this just to get 3000 watts out of a single inverter so why the battery bank ? Why not just run the inverter directly off the alternator as a store bought generator head is powered directly off the crank shaft and don't use battery banks so why the need for the battery bank . 3rd why didn't you just spent $350-400 on a decent 3000 watt store bought premade gas generator if all you need is 3000 watts I mean you really spent way too much money and Installed way to much unneeded equipment just to only get 3k watts, seems like alotta work for nothing and a large waste of money to me I dunno maybe Im missing something but I don't think so. I mean 40feet of cabling dude seriously, and 12 batteries in your bank all in the end just to get 3k watts , which can be had from any store bought $400 or so generator so yeah what is the deal what am I missing here lol.

[@stevethompson1488]

because gas Engine are Not very efficient You lose most of the energy going out the exhaust, gas Engines are more efficient under load but Not with small load and If You do Not want to continuously run the Engine then store the energy Into batteries and use large batteries and power Inverter

[@ChaplainDaveSparks]

"Chinese junk"? Isn't that what they call some of their boats? 73 de AF6AS

[@NSNorfolk]

Nice overview at the system level. Perfect for charging the batteries on cloudy days.

[@AdamBatchelder]

So a few things that would help your set up. 1 if you are running 1 to 1 why not ditch the belt and use a direct drive and get your 10 percent back. 2. If you pull the regulator rectifier out of the altunator and run wild ac for the run to the batterys and re install the regulator rectifier there your line loss will be much less.

[@sedevacantist1]

That is great advice, also save a lot on copper wire which must be over three hundred dollars for 1/0 welding cable.

[@hexinli]

I really appreciate that you exposed your challenges as well as your successes in the video series, and especially appreciate that you used Anderson PowerPole Connectors for your DC setup, but you should never, ever setup a PowerPole matrix where your connectors interconnect with different colors. Give your setup another thought - your connectors should connect with like colors on the opposite side.

[@robertpolicastro9403]

That is an under drive pulley! for under driving the alternator so the belt doesn't come off.

[@robertpolicastro9403]

yes its called a racing pulley but it under drives the alternator.

[@davidca96]

Suicide cable! Haha.

[@jerrymctee5996]

He should have a transfer switch. Do it legal do it right.

[@DougHanchard]

One comment and I'll leave it at that when doing anything with generators and connecting it to your home. Deadman Switch. If you don't have one, chances are, you are in violation of 99% of electrical building codes in place throughout North America. #StayAlive

[@trongdao7459]

Doug Hanchard GREAT IDEA.

[@grpsmartgrpsmart5285]

You need Drive Belt Tensioner Pulley :D

[@Mike588]

Now add a couple of 100 or 250 watt solar panels to charge on sunny days, less running of your generator, and is just another backup.

[@Bassguitarist1985]

Great video knurlgnar! Though still kinds suprised you havnt invested into a proper interlock system. You spent all the money on inverter, cabling, and engine. A $20 double pole breaker and ~$150 interlock kit more would make this setup much safer than with suicide cords. Great job on muffler and exhaust btw!

[@blackz06]

What are suicide cords?

[@5.43v]

@@blackz06 male to male

[@Rumple1968]

Can you run 2 ALTERNATORS @ the same Time either on a 2ND PULLEY or Larger BELT in a TRIANGLE style set up?,