How To Fix A Generator With No Compression That Won't Start

Generator won't start and has no compression?
Watch this video to see how I repair this compression problem without replacing any parts!
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Easy to follow and thorough step by step tutorials do it yourself (DIY) to help you with your broken lawn and garden equipment including snowblowers.
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[@ezelk1337]

I went through everything on a Kohler propane generator with 30 psi compression. It only had about 20 hours of use on it total. I finally checked the valves and they both had zero play. I set them just like you did and it started right up! You are helping out a lot of people with your videos. Subscribed .Thank you

[@petersack5074]

what ?? the factory assembly didn't set them right, as 20 hours would NOT WEAR THAT MUCH...?? or just too soft a metal on the ohv parts...

[@mwechtal]

Our Onan generator specified valve lash check and 1st oil change @ 25 hrs. Valves usually loosen up a bit at first as parts polish themselves while running. Vibration can either tighten or loosen the adjusters though.

[@danielswink8348]

Thank-you, Don! My DuroStar generator is 7 years old with only about 100 hours on it. On 12-23 the power went out. It was about 5 degrees and my generator absolutely would not start. : / All it did was backfire once about every 15 pulls. I researched for weeks, tried new oil, new gas, new spark plug, clean air filter, low oil sensor disconnect, starter fluid and even a new carburetor with no effect at all. Then I found your video. I got a set of feeler gages, I adjusted the valve clearance and about 20 minutes later my generator started on the very first pull and it runs great! 🙂

[@chrisvill54]

With KZbin you can fix anything. I was having no compression on a predator generator. Took the valve cover off and realized both valves had no gap at all when at top dead center. Adjusted them and that fixed the problem. Thanks for the video. Very helpful.

[@1hjehje]

I didn't think that the valve adjustment would change that much over time. An excellent video .. Thank You!

[@davidhiggins8505]

Thank You! ❤ Our Ryobi generator had a very similar problem(stuck valve). And, your video and expertise helped me fix the gen, and avoid a long drive and hassle. Great information, well delivered.

[@Dave7160]

Hi Donyboy73, I just wanted to tell you personally that I have tried everything to get my generator to work and it wouldn't then I saw your video about the valve adjustment and It was the exhaust valve that needed adjustment I did the adjustment of 004, 102mm and put it back together and the generator fired right up on the first pull, it was thanks to your video, you should be nominated for an Emmy award for all the help you give people in getting their equipment running, thank you much for all your help please keep up the great work big thumbs 👍to you sir.

[@eosjoe565]

I always re-check the gap after tightening the lock nut as 9 times out of 10 it changes the gap slightly. I normally have to compensate by leaving the gap a couple thousands loose prior to tightening the nut. Then when the nut is tightened the gap is right where I want it.

[@piratekiller13]

Did exactly what you said after buying the feeler gauge and I’ll be dernd if it didn’t start first pull! Thanks for the video and easy to understand instructions!

[@MRrwmac]

Didn’t know that was as much of a problem on new machines! I would have thought a head gasket. Thanks for the tip!

[@barrybebenek8691]

Weird that these things have the clearances change so easily. 🤷🏻‍♂️ Thanks for another easy fix. 🇨🇦👍🏼

[@bobfrey6953]

Have a Smarter Tools 7500 W dual fuel generator that I use at our off grid cabin. It was becoming increasingly harder to start and finally would not start. Checked the compression - ZERO! Saw this video and checked my valves (just like yours, the intake was loose, the exhaust was tight). Adjusted both to .004", put the valve cover back on and wouldn't you know it - started RIGHT up! Thanks!

[@RayTuttiver]

i have 6 generators and 4 of them would not run...but since watching this video now they all run great thanks a million

[@herbertsjeffrey]

Super clear. I enjoyed learning from the cause to solution. Great teacher!

[@rstephe]

Wow! Glad I am subscribed to learn this one. Never even knew this was an issue. Had valves back out before but never tighten to keep open. Thanks for sharing.

[@josephpuchel6497]

Hey I have found quite a few of these particular engines having to adjust valves. Excellent video Donyboy

[@sailme2day]

Thank you Don , your skills and honesty is appreciated .

[@steveb.6267]

Great video as always. Have 3 Champion generators, my oldest one has close to 3000 hours on it. Other than replacing the pull cord on it and regular oil changes haven’t had any problems with them. I never thought they’d be that good when I first bought them but now I have no trouble recommending them.

[@kevinsweir]

I have always had problem starting my Champion Generator from day one. Fixed in 10minute. Thank you for all you videos and advice.

[@robkenna2795]

Thanks enjoy your videos, and usually learn something new. You are the type of mechanic everyone would hope to know. Good stuff.

[@papajon6715]

You are offerring a great public service. I want to know who the six people are that dislike this video, are they just 'professional malcontents'?

[@donyboy73]

usually other guys who do small engine repair and can't make videos

[@papajon6715]

You have helped me with several mowers with problems over the past few years and I greatly appreciate your invaluable expertise. Professional jealousy had occurred to me but I didn't want to say what flashed across my mind but didn't these bastages' grandparents teach them about the golden rule or even just keeping your pie-hole shut if you can't say something positive? Sorry...

[@milwsdl39]

Well I just picked up a generator for half of a local yard sale page guy said he ran it went low on oil but then it doesn’t seem to work now no compression so hopefully it’s the valves thanks for the video

[@butler386]

Good old valve adjustment. I needed that reminder. Great video..

[@manocox1215]

had no compression on my generator just followed your instructions and it started first pull thanks buddy really helpful

[@LessThanHandy]

Another lesson for me from the very best. Thank you.

[@watermanone7567]

Great job Donny, I have found many of the 13 hp Honda's with the valves way out of adj. and making them extremely hard to pull over with the rope starter. Thanks for the video's.

[@scottfirman]

I always check the valves on any OHV engine that has starting issues after checking the carb. As you said, no compression is the biggest give away on those engines. Especially riding mowers in really good condition. I also pull the plugs first thing. An oil soaked spark plug means bad news. After seeing a no oil plug, I know then its just valves. I have had stuck valves on older generator too. A poorly maintained generator is just asking for trouble.

[@elpunto231]

RC Hobbyist Extreme ohh nice to see you here ;) i love this chanell to ;)

[@skipproctor8979]

Engine won't start, no compression. Automatic valve job. Thanks Don.

[@bobmcl2406]

Clear, well explained, and helpful. Thanks once again Dony!

[@zensterful]

This is why I love this channel!!!!!

[@jimmeyer803]

BIG "D"... THANK YOU. I just saved myself 200bucks in parts! I'll never trust any local engine guys again without looking for a fix with you 1st!

[@GrampiesWorkshop]

How's she goin'? Air, fuel and spark is all you need to make the engine run. Well not quite!!! You also need compression!!! Great video and thanks for sharing!!!

[@matthewkallevant7558]

You need a nice tight space to make the air spark and fuel go boom 💥 😂

[@michaelj38]

Thanks for this video. My exhaust valve was out and after I adjusted it the engine started right up. Engine only has nine hours on it.

[@stevenmchenry9276]

Donyboy I'm going to try it but I have not been having good luck. Thanks for the video.

[@pauldelamere]

Thanks donyboy I will check and sort my one tomorrow, I just bought it from auction site its nearly new so was glad to hear you say it can happen to nearly new as well, thank you from Edinburgh Scotland 🏴󠁧󠁢󠁳󠁣󠁴󠁿🍻👍

[@donyboy73]

No problem 👍

[@pippomonti6698]

Grazie ragazzo, ti seguo dall'Italia. Fantastici video. Sei il migliore professionista di KZbin

[@bopalouie]

Thank you! This got my little Generac 3600 going

[@jenntek.101]

Did you find TDC Before you adjusted the valves? On a Briggs (for example), you go to the compression stroke at TDC, then a 1/4 turn past TDC, and check your valves; BOTH should wiggle prior to your adjustments; If you are at TDC, and you do not have any wiggle; you are in the "Non" compression stroke. Just thought i'd put that out there, unless someone else chimed in... I'm not going to read all 230 comments to find out. Nice video!

[@mikemcgrath5905]

Thanks for the great tutorial! Very clear instructions. Very informative! Thanks for taking the time! You rock!

[@160sura]

Great video! I am sure this video will save me a lot of time and money in the future! Thanks!

[@rasmo243]

Great tip always worth checking what a difference that made to the compression

[@jill4618]

Really appreciate the video, our new champion all sudden decided it didn’t wanna start. Pulling the recoil I could tell no compression. Upon opening valve cover, both valves were sloppy loose. What causes this issue? Never had this issue with my firman genny, in fact we bought the champion to replace my firman wit 3800 hrs on it. When the champion refused to start, the firman started first pull.

[@Jake-jw3sk]

Hi Don. I've been looking every where on internet and can't find information on how much compression a generator is supposed to have! My generator that I'm working on is 2300 watts, it looks about the same size as that one. By the way great video, like always. I am interested in making a business like yours when I'm older.

[@philliphall5198]

90-120 is plenty

[@holdemNE1]

Wow, nice simple fix. Thanks for sharing.

[@mikemcgrath5905]

Awesome vid again, Tony! I've learned so much from you. I sure wish you lived in my area! I would keep you busy, for sure! Really appreciate you taking all the time and effort to make these videos, and would also like to complement you on how well the videos are shot. Nice camera angles and closeups, and you're easy to understand and listen to. You, my man, rock and roll! You are the absolute best!! Thanks and much appreciation and admiration from here just north of the Motor City in beautiful Michigan!

[@transportationdisasterprev6250]

Nice video. All info with no BS. Thanks for your time

[@thelawnranger184]

A genius at work.

[@chuckvoss9344]

Very good. First time I have heard of this type of problem. Tks.

[@genehensley767]

You're a genius no doubt about it

[@f.demascio1857]

Seeing those valve adjustments reminded me of the many VW's I owned in the past. Seems like I was adjusting those damn things every other weekend, & #3 was always tight due to the excessive heat at that part of the engine (Type 3's.)

[@gigiraymond9267]

Thanks Dony for the information , this is very important to know . Thanks for the video , God bless you .

[@alvarosantibanez5565]

I like the way you explain

[@angrybobking5083]

I have a Honda EB3000c generator that died on me ice fishing this year never ran again. Just did a compression test wet/dry and failed miserably. Was gonna just throw it away and go get a new one when I thought " ah I'll just check and see how bad it is to tear these down. Stumbled upon this video and that exactly what it was set the valves to .004 and started first pull. Can't believe I almost threw this away when it was a 3 min fix!

[@sajid390390]

Hi, Thank you so much for sharing such nice info. My generator is starting correctly and running the load correctly. But there is one issue. The generator is bubbling too heavily. It has too much vibration. Looks like it will break the frame or some parts of the engine. Please guide me on how to fix it and make it smooth. The frequency is stable and controllable. Voltages are correct. Only too much vibration and bubbling.

[@BradleyRains]

@donyboy73 .. thanks for the video man!! Saved my butt! This was the exact issue. Dealing with the power outages out here in California having to rely on generators. Thought mine had cooked a ring- nope- you totally saved the day! Didn’t have feeler gauges but got it good enough by feel and using a headlamp in middle of the night. Got power going just in time for the mrs to get home and have heat and lights. Thanks Again!

[@rexbenoit1073]

thank you I think you just solved my trouble with my champion generator.

[@themishernandez1738]

Hi, great videos super easy to understand, I have a problem with the battery connection to start, could you helo me with the process of instaling the battery in a gasoline engine

[@rdpaullin]

Thank you Donyboy73, excellent video. I appreciate your information

[@BigDmike24]

Awesome fix. Didn't know that information. Thanks!

[@mattludlum1916]

Just bought a "broken" generator with only 1-2 PSI compression - cylinder seemed ok so a quick search later brought me here. Exhaust valve was very tight with no play. Loosening it and setting to .004" seemed to restore the compression - I could tell just by air whooshing out of the spark plug hole. Put it back together and the generator came to life off started fluid. It'd be good to have a general "guide" to compression for small engines, including what "unloaders" will do to the readings.

[@charlesroberts3910]

Thank you for the tips Donyboy

[@kennethwalker3028]

What happens to cause the rope to snatch back, is that valve setting also?

[@jamesws3]

How is the "One valve open, one valve closed" method different from adjusting with both closed and piston at TDC on compression stroke as I've also seen? Either way, great video as always!!

[@cedricmerritt7664]

Great video! I knew it was the valves!

[@daydaysaint6657]

I have this jonsered st2261e snowblower about a year old no spark anything you could tell me to do or try anyway I think your KZbin is great thanks Dave

[@unfundedopportunities7278]

Donny, if replacements for carburetor-mounting and exhaust gaskets are not available, what do you think of cleaning both sides of existing gaskets and coating with gasket maker? Making a gasket is difficult.

[@zx8401ztv]

Those adjustments do seem to wander off over time, easy to forget :-)

[@lifeintnchevalier]

Same issue on my Preditor 3500. More China junk. My Honda 3000 just runs on, after 1000 hours the valves lash still in spec. I feel it is poor steel on the seats or just incorrect heat treatment. Good video, thanks

[@iamrichrocker]

with Honda being so darn expensive i have bought a Champion and am very happy...this video will be great reference if ever this happens..thx..

[@barbeonline351]

I am just learning... This seemed to be quite a departure from other No Compression videos I have seen. No mention of scored pistons/cylinders? Is there a tip-off that says to check the valves first rather than pull the muffler and have a look inside? Is it a 4 cycle vs. 2 cycle thing?

[@jefferyoneil944]

Thanks Donny

[@colinevans7134]

Another good video from croydon surrey England 👍 👏 👍

[@lebaroncars]

Mine doing the same great video thanks

[@vetterfellow]

Outstanding DB73; The first thing I thought of was rings among other culprits :-( This is why you get the BIG money :-) Thanks you for another video My Friend, God Bless !!!!.

[@rickster7834]

Another great video and tip. Thanks!

[@RangerTim]

Great video

[@Honestandtruth007]

So Valves adjustment on Generator Is Similar of Lawnmower Valves adjustment 👍😅👍

[@donyboy73]

yes

[@clintsmith3408]

I have zero clearance on exhaust side no matter where at in the stroke. What Could be the issue?

[@clintsmith3408]

Figured it out. The valve keepers are being worn down, replaced and 1.5 hours later, same thing.

[@davidsteinfeld9123]

Hi Don I have a powermate 5500 And just the other day everything was fine then I go to start it and it's makeing a clunking noise as I am pulling to start don't want to start doing things till I am sure I know what I am going to be doing now I have had this machine pretty sure since 20011 it's got 188 hours of run Time on it till it started makeing noise and now it will not start at all Your input as to what this could be and how it can be fixed and the if is still in question Thank you in advance ☺️

[@garrettstevensen2467]

Damn I love this channel!!!

[@robertmailhos8159]

Great fix on the motor my canadian brother 😄😊🙂😃😁😀

[@clauslundberg9224]

Super useful - thanks for sharing

[@themowerman]

Great job well done

[@petersack5074]

the factory assembly settings, must have been off, or too much wear, and maybe too soft a metal on all the ohv parts...??? which ? or maybe both ?? i got a old yamaha eh2800 gen which, seems to have low compression. free at garage sale, and tank inside is rusty, but overall seems ok. no rubbing or other noises when pull the start rope....got to redo carb too. any advice on valve settings ?? plug is ok, good slight grey color....thanks for the advice....in central alberta....

[@nashguy207]

Good Job donyboy great tip for people!!!

[@soldierscraft9213]

Any idea why a champion generator would shake a lot where it moves and spark plug was dry with lots of carbon?

[@tomycodd]

Thank you Don for the great video! Where do you get your parts for Champion generators?

[@thomasramsay4286]

Have you ever run into a 16hp Wen generator that breaks exhaust valves? Twice it has broken off the top of the valve. No damage to the piston so I'm suspecting a valve guide that is a bit under sized. Any thoughts would be appreciated.

[@michaelchilders1658]

Awesome teacher!! Thanks so much!!👍🔥

[@aronschmidt6108]

Make sure you’re on top dead center before performing valve adjustments. Other than that great vid!

[@JimFixIt74]

Great video Don! Very helpful.

[@lostfound8112]

Great vid as always bruther

[@shadowfox929]

Great video. On my compressor I have so much compression I can't use the pull cord at all. I always have to use the battery start. What do you do in a situation like that?

[@edwardkawecki8101]

Isolate the problem first. Is it an eng. problem or is the compressor not releasing head pressure after it is run. If engine problem, check valve adjustment and make sure auto compression realease is working. Also check that cyl./piston is not hydro locking from too much fuel. If eng. is ok, drain down air tank and see if you can easily manually start it. If you can your compressor may not be bleeding down the head pressure and may have to be corrected so you can pull start easy when air tank is full or partially full. If you can disconnect the compressor from eng. that may be the easiest way to check the eng. problem first. Just my take on it after doing a quick precheck on all the normal things first. Hope it helps.

[@shadowfox929]

@@edwardkawecki8101 Thanks for taking the time to reply to my post. As I was reading I couldn't figure out why you were talking about air pressure and the like. I went back and read my post and realized I wrote "compressor" instead of "Generator". I guess my feeble mind wrote it that way because I had compression on my mind. It was very kind of you to take the time to respond and for that I thank you. All I can say, is it is hell to get old. (I'm 74...LOL)

[@edwardkawecki8101]

You're welcome.

[@jamesbolt7090]

Thank you!

[@eosjoe565]

It appears like it was the exhaust valve that was too tight. Having an exhaust valve too tight can burn the valve. If you have to choose between too tight and a bit loose, a bit loose is better. Of course, having both properly adjusted is the preferred option. :-)

[@clsmallenginerepair3814]

Hey man,, i hav a hot frame on a troybilt,, New solenoid, battery..just clicks when i use the key. Was gonna use jumper cables to bypass the system, to check starter. I hook the cables up to a battery, as soon as i touch the negative side to the frame, starter turns.. Any thought? Thanks

[@joytrucker5709]

I ran out of gas while my generator was running and under a load. Added new gas and now it won't start. I'm going to try and do this compression fix. Do you think it will work, or is it something else?

[@Pitross20]

Great work as usual .

[@jamestackett2879]

Good video thanks for sharing.

[@ronraby4561]

Thank you sir

[@ebfromwyoming4118]

great video sir thks