Onan 4000 watt RV generator Repairs, Service, and Common Problems

I did safely return from my cross-country 2021 Allegro RED delivery to Kentucky, only to get back to work on this Jayco Greyhawk.
This Class C has what is known as an Onan 4KY 4000 watt RV generator. After installing the new AC unit, I spoke to the owners and discussed the issue of the generator surging sometimes. They agreed that ontop of the service they wanted performed anyway, to repair the issue with a new carburetor, as the old one was having some issues. I discovered the fuel line was also cracking, rigid and needed replacement too. I know, some would say just re-build, but re-build time is still expensive with no assurance the problem is fixed at the end, so I chose to replace and instruct owners how vital running it one hour a month is. The oil service is ridiculously easy, and DIY is a great way to recoup the money spent on a new carburetor :)
Thanks for watching!
Onan 4KY carburetor p/n A042P619: amzn.to/3BMGzUm
Air filter p/n 140-3280:
amzn.to/3QSm7po

[@Gatorwatch916]

Thanks for NOT including background music over your narration!

[@PeterPedroA.Cintron-421Pc]

I'm 60 years old and every time I see you do work like this I feel that I should be right there next to you helping you up at least holding the camera 😊✌🏽

[@AZExpert]

I'm terrible to work with

[@PeterPedroA.Cintron-421Pc]

@@AZExpert Terrible my dad was terrible but I kept my cool and just listened and worked with him I found out that if I just kept my mouth shut and paid attention that I Wood learn and I did learn that is why I was always The apprentice plus you have to remember my dad was in the Army for 8 years so I had to watch and learn he was a great mechanic back in his time he taught me everything I know now ✌🏽

[@robertlarsen5979]

I'm 73 and now my mantra is "I used to be able to do that".

[@Voyager23B]

@@AZExpert I'm sure your are hyper-focused and repairs must be 100% correct! If that's what being "terrible to work with" is, I'll take it. I operate a mobile RV service company as my second career.

[@stevemarquez9628]

I got tired of replacing nearly $400 carbs so I went with an Amazon carb. It's been 3 years, so far so good. At the time I couldn't find a carb and figured I would only be out of $30.Honestly I think the biggest fix was the in-line fuel shut off. I run my generator once a month and after an hour, open the compartment and cover and shut off the fuel. It runs dry in 2-3 minutes and fires right up next time around. If I'm out using it I don't bother until we are packing up. I wish I had put the in-line shut off in when my generator was new, it probably would have saved a lot of money and headaches.

[@AZExpert]

that's a really good idea too. Thank you

[@NackDSP]

I use my fuel shut off valve and now also open the drain screw on the float bowl. The previous owner of my RV installed the valve. Unfortunately he cut back the corrugated plastic heat shield on the fuel line so I had vapor lock happening on hot days this summer. I finally figured it out and put more shielding on the hose and aluminum tape on the heat shield. Weird that they went out of their way to run the fuel line right by the cylinder head on the way back to the carb. If the fuel line is too long it makes it worse.

[@bobblack3870]

No matter what gas-powered motor I have, if it will not be used in the next two weeks, I also turn off the fuel and run it dry. Solves lots of maintenance problems. Buy a cut-off valve to insert into the fuel line. And if your motor does not have a fuel filter, consider it mandatory - but an RV setup should have one already.

[@henryvalz93]

Do you have the link for the Amazon carb?

[@TJ-bl6lr]

Doesn't that trip an onan error code for non normal shutdown?

[@dinosaur6756]

Omg. $500 for a replacement carb is utterly insane. A tech could easily charge $1000 or more to do the job you just showed us. Spend the 5 minutes to drain the bowl if you're not planning to run the genny or before storing your rig, people. Great stuff James.

[@AZExpert]

Thanks for watching! :)

[@dinosaur6756]

@@AZExpert Are you kidding? I've watched every video you've ever posted on the channel. One day I'm gonna show up, having rented the work space next to yours, you wont be able to shut me up and I'm probably gonna need to borrow some of your tools...just kidding James, I have my own tools. Lol. No really, I love the channel and have learned loads of stuff because of it. I know it's a pain in the ass to record stuff when your trying to do a job so I truly appreciate all the effort.

[@stevegordon5243]

Excellent video! Really appreciate you taking the time to film this! Now I know how to service my Onan 4000 Generator

[@AZExpert]

You are welcome!

[@alexchliwnyj5941]

Great video as always. I found something that might be really helpful. Last year my Onan 5500 wasn't running right so I removed and cleaned the carburetor only to have the same problem this year. After watching countless videos I finally found this on KZbin, "Updated Onan Marquis Gold 5500 Generator How Stop Carburetor Surging Without Removing Carburetor." In the video he removes the plastic cover that restricts the main jet altitude adjustment range . I carefully pried off the plastic cover without removing the carb.and unscrewed and cleaned the jet needle. I screwed it in until it was fully closed and then opened it 3 turns. It started right away and his rich/ lean adjustment procedure got it running perfect. Without the plastic cover you can adjust the jet and compensate for manufacturing tolerances and varnish buildup. Maybe everyone is replacing Onan carburetors because they get a little varnish and there is not enough adjustment range so it runs too lean. I just could not accept that such a simple carburetor could go bad and have to be replaced.

[@JohnSnow-de4kd]

Thanks very much for this video - I was able to replace my carb (and gas line) after being without a running generator for over a year. My model was exactly the same as the one in your video and there is probably no way I would have been able to do this job without watching your video a few times - Thanks! I have to say though, that I had a lot more trouble getting the gaskets in place and lined up in order to get the two bolts put in, but I eventually was able to get it put together and it's now purring like a kitten!! You are also correct when you say that these OEM carbs are VERY expensive...I live in British Columbia, Canada and the purchase price for the carb was $997.89 + tax (Canadian dollars), plus gaskets. Took a chance a bought it after viewing you video and thankfully it worked!

[@CrazyMooseManor]

My father had one that wouldn't stay running after sitting up for a few years. Tried cleaning the original one and could never find a rebuild kit. With no luck.. After seeing new prices and knowing he was going to sell it since he was about 85 at the time just put a knock off one on it. It ran fine for the few months he had it before it sold. After watching your video I would go with OEM for my personal toy hauler. Now I need to check the voltage and hertz after watching your video. Great video and content as always.

[@AZExpert]

Thanks Darrin!

[@corrtechit2901]

So nice to see the proper steps. Thank you so much!

[@AZExpert]

You're welcome

[@iglapsu88]

Thanks James! Using ethanol-free fuel (if you can find it) can help to avoid spoiling fuel and varnish build up in addition to running once a month under load. Love the great content! Even watched the annoying commercials to help with your KZbin stats!

[@AZExpert]

Thanks for the info! Sorry, youtube puts those breaks in automatically, but I took some out. thanks for letting me know.

[@rnreajr9184]

I second the use of ethanol-free fuel. When I store gas engines for extend periods of time I prefer to run them out of fuel first (until the engine dies) to remove any remaining fuel. I also change the oil at this point to also get any fuel-contaminated oil out of the crankcase. It seems to work for me. The downside with an RV is that (I am assuming) the generator runs off of the RV's fuel supply, so that would mean using ethanol-free fuel in the RV also, which, around Utah at least, is a bit pricier than regular unleaded. But it does have more BTU's than regular unleaded with ethanol, so there's that. If you must use ethanol'ed fuel in the RV, add a tap to the generator fuel line so that you can draw from a separate tank with the "clean" gas, or at least run it through the generator from a gas can at the end of the season. It's a lot of extra work to do, but it will help make the genset last longer, and RV's should be worth the extra care to help them last longer.

[@georgec4917]

I only use ethanol free gas in all my small engines I also put it in my Harley when winter rolls around and never have a problem when they sit for extended periods of time

[@jeffwhite3021]

These run off the motorhomes main tank. Ethanol-free isn't practical.

[@iglapsu88]

@@jeffwhite3021 good point.

[@Centexgem]

Great detail! I was able to clean the carb with SeaFoam and other products. But it took a while. Now running it monthly has maintained function. Pushing the button once a month is easier than what you just viewed here.

[@AZExpert]

Great job!

[@timjohnston9764]

Thanks for the vid. Just purchased a 2002 winni with the onan 4000 and feeling much better with understanding its issues and maintenance. It’s sad that Cummings parts are so expensive and yes their labour is too. Thanks again for sharing your knowledge and instruction! Tim from 🇨🇦

[@KevinCoop1]

James, this is the exact video I was needing! Our RV we bought must have sat for a while before they sold it to the dealer. It was running exactly like the one you showed. Hard to start and loped badly. I’ve run quite a bit of Sea foam through the RV and Generator from the tank. Now it runs much better after it starts, but is hard to start. In my mind, I can’t justify $500 for a replacement OEM carb. Just too hard to swallow that one. Thanks for the video! Respectfully, Kevin

[@AZExpert]

Replacing the whole thing is a much bigger expense in the long run

[@MR_UNOoo]

I seen a video where a guy hooked gen up directly to a gas can. And dumped double the seafoam init.. cleaned it right up..

[@maverickrider4591]

Very professionally made, and at a pace I could understand, no skipped overs, a true pro is a true pleasure to watch. Questions: Does this Gen have an inverter for computers? How long can I run this on a fresh oil change for, I mean hours in a row without damaging it. I am picking up a 1987 Fleetwood Bounder that the seller bid on at an estate sale to bring home his purchases. Drove it several days ran well for him, selling it to me to recoup his bid funds for it, doesn't use it, knows nothing other than it doesn't leak, and runs well. Used it once, but key starts regularly. I have taken chances like couple times before, like my 95 YJ I got it for a price no one believes, went completely through drive train end to end at differentials, interior, brakes, shocks, top etc. Runs fantastic, looks OK too pretty people steal it. Now people stop me offering 7 to 10k, never going to sell it though.

[@dalerice9461]

Thanks James! I was shocked at the prices the factory is charging. I've been working on engines and carbs for over 60 years and decided to give the aftermarket carb a shot. I asked on our RV forum and found other have used the one I bought for $40 on Amazon. I also thought $250 for a fuel pump ridiculous and opted for a discount one at $20. Time will tell how well they hold up but I can afford to buy spares at those prices. Anyway thanks again for the great video and comments. One thing I messed up was the choke lever on the carb wound up in the wrong position (front) so I had to loosen the carb to swing into place (rear) and all was right with the world. Not an easy job for sure when it's 115 Degrees outside here in AZ.

[@AZExpert]

Yes, this video hasn't aged well with the carb price doubling so fast. And I have made the choke mistake too

[@kmr7825]

Great video, I used it as a reference to replace not only the carburetor but the fuel pump as well (gen would crank but not start, replaced with all Onan parts). It runs now, however, it surges. Oh well, the joys of RVs.

[@johnwren3976]

I was fortunate to open bowl drain and flush carb through intake hose with carb cleaner to remove varnish. Changed filter and pump for good measure. Golden...👍

[@HighCountryRambler]

On my class-C the generator is always having fuel problems and doing another carb swap currently. I'm seriously thinking about removing the generator and adding another larger inverter & charge controller and 2 more solar panels + 2 more LiFePo4 batteries and running the 120 vac off solar. My 2 current LifePo4 batteries have a 20 year warranty, same as my panels. Far longer than my new carb will last.. Thanks for the video..

[@keithsaunders2532]

Mine must be a different model. Rubber fuel line goes to the pump. Which I replaced when I checked it for fuel flow (none). Then it has rigid lines from the pump to the carb. Had the same pulsing issue. Local Cummins service center fixed it. Damn carb is $700 from Onan. And now it's slow starting and pulsing again. I'll do the Seafoam thing again. Got another pump just in case. And I'll always keep a spare on hand. You have so much hose distance for crap gas to live. I think that's the biggest issue. Bypassed the control module on my Quickie step too. Outrageous price. Double pole double throw momentary switch in the stair area. A small inconvenience but a simple fix. Thanks James. You have the best videos for us that think we can DIY. LOL. I've even replaced awning fabric. Touchy situation but not that hard. Replaced the ratchet end assembly when I did it. Like brand new. Wish I could find some good awning fabric. Or maybe make or buy a cover. Amazon fabric doesn't last long. Any suggestions? Window awnings are original cloth and work great.

[@I_wish_I_knew_something]

I hit the bell so I know when you put a video up. I can’t get enough.

[@AZExpert]

Thank you! and welcome!

[@kennyblemel2503]

Thank you. The best explanation and how to I have located.

[@AZExpert]

Glad it was helpful!

[@Georgiagreen317]

Before purchasing an expensive carburetor, try adjusting the altitude adjustment right under the fuel line. That's what it's there for. These engines are sensitive to both altitude and temperature variations. Oftentimes times a slight adjustment will cure the surge.

[@FreedomIsntFree2023]

Well done sir!! Loving the full length, step by step process on how to remedy this situation! Thank you

[@AZExpert]

Glad it was helpful!

[@j.traviscox5536]

Outstanding video! VERY helpful. Love the clear, step-by-step instructions.

[@davidpeel8431]

Excellent video, clear video, and instructions from someone who actually knows what he is doing, you are the best. Thank you so much.

[@rbnhood39]

James you never cease to amaze me at your knowledge of everything motor home related.

[@AZExpert]

I just play a mechanic on TV

[@rbnhood39]

@@AZExpert , you are up for an Oscar then.

[@proudtexan5513]

You do damn good quality work!!! Very detailed!!

[@AZExpert]

Thank you!

[@05rickie]

Great video for R&R the carb,much appreciated,my 4 year old Onan 4000 started doing the same surge,not too bad but the surge was there,I first replaced the fuel filter,532 hrs. on the original filter,surge was still there,I drained the fuel from the carb and removed the solenoid and float bow ,l filled the float bowl up with carb cleaner "mechanic in a bottle" from Walmart and let it sit overnight,next day I sprayed an aerosol carb cleaner in the float bowl and cleaned it all up,re assembled the float bowl,started up the gen and she purrs like a kitten,surge gone,I would advise just removing the float bowl and give it a good cleaning inside before replacing the carb.,it just might save you a lot of time and $$$$.

[@dgsantafedave1]

I have a reminder on my Mac Calendar to cycle my genset once a month. I also if I can buy the ethanol free gas in either Oregon or Nevada I remember replacing carbs on my old genset it was easy to do, but, expensive. I think that I will follow Steve M's advice a put an inline fuel shut off on mine sounds like good idea!

[@AZExpert]

Maintenance reminders are always a good idea

[@whatdontknow-jc7ve]

Great video, easier than i thought. I have gas gas leaking down from fuel pump, so now i know how to get to it. Might be hose only, i didnt drain bowl before storing it in Kenai AK. I will see how it is after some work. Thanks again

[@anthonyb2334]

Thank you for an update excellent video. I’ve had a number of carbs replaced over the last 25 years. After your video, I might try it myself next and if it happens again. I drain the fuel now. ( Learned the hard way this must get done). Great information. Thank you

[@AZExpert]

You're welcome

[@FacetsOfTruth]

You are awesome! I wish you were here in Dayton, Ohio. I need a guy for my 33' Pace Arrow. Leaking Master Cylinder, and it will still roll when in Park. It starts fine. But it will roll away on you even though it is clearly in Park. I need a guy like you. Love your videos.

[@DavidHBurkart]

Stellar fix and replacement James! Appreciate the info and troubleshooting tips! Those carbs will varnish up quickly if infrequently used. Gotta run 'em or they will fail to run correctly or at all when you need them most. Always tricky steps getting those gaskets on right.

[@AZExpert]

Thanks for watching David

[@steves3688]

When I bought my used rv and the onan had hardly ever been run -12 hours on it during 10 years(still actually started but surged badly)...lol......I did the seafoam injection directly to carb and it helped a little with the surging but it was the fuel pump that was the real culprit. It just wasnt delivering enough fuel...replaced and fixed. I would like to add that MANY people dont know about the elevation dial on the carb and that can make them surge and/or run bad. YES YES YES.....run them under load regularly and I always seafoam my fuel when I know Im not going to use my rv for a while...have used it all my life and it is excellent fuel stabilizer...AND also when Im not running my rv for extended period of time I try and get as much NON ETHANOL fuel in it as I can....call me over devoted!!! LOLLLLL

[@AZExpert]

Thanks for the advice for the subscribers!

[@kellyyetter1355]

Well I'm a carpenter and a drummer. Not really good with mechanical stuff. I know I could take it all apart, getting it back together is another story. Lol ! That was a great demostration tho brother. Thank you for sharing. I fo have the same generator only it's in a tighter spot on my camper. Ugh

[@contactmiller]

My 1990 Onan 2.8 had a bad magneto. That took me a lot of troubleshooting to figure out because the failure was intermittent. I had to pull the flywheel to change it. Big job on a small motor. I was able to easily dissemble and clean the carb. Pretty similar to a lawn mower. Runs great ever since. Lawnmower magneto is $10, Onan magneto is $150.

[@PeterPedroA.Cintron-421Pc]

My dad was a great mechanic he learned his trade a new Army along with infantry but I used to help him out a lot working on cars he would do side jobs on vehicles and up to this day I do work on vehicles

[@AZExpert]

Awesome

[@dytetonic]

Great attention to detail..doing it right, and especially keeping clients safe👍🏻

[@AZExpert]

Thanks Diane :)

[@23thebull]

I don't have an rv yet but I'll know what to do to service my generator..thanks you the man 👍💯😎

[@AZExpert]

Have fun looking for one

[@RecumbentRider]

Excellent video! One noteworthy mention, is like 99% of the other videos I watched, no one mentions how they get past the problem with the choke and throttle butterflies closed at the same time so the carb will slip out. One KZbin video I watched said they had to bend the tab on the choke linkage up so that it would clear the throttle linkage, thus enabling both choke and throttle butterflies to be closed (counterclockwise) and slip the old carb out and the new one in. Also, it would be helpful to know how you got the gaskets to line up for the bolts to pass through to secure the carb in place. I read in Cummin's service manual that we should not use gasket sealant to hold the gaskets in place. Besides, it's such a tight fit, I'm not sure that it would hold it on. I did find that pushing on the wall (side with air filter box), that created a slight bit of space to allow you to adjust the gaskets for proper fit, but even then, it's pure luck or Devine ntervention in my case, that allowed me to successfully get the carb installed and work first time without leaks. So again, if you could go back and add an addendum to your video on the subject of getting the carb out and new one in as it relates to those butterflies, that would be a huge help. I didn't like bending the tab on choke and then having to bend it back into place (making sure it was back to a 90 degree position so throttle would open and close like it should.

[@loridubiel1638]

Thank you! I followed your instructions and my new carburetor is working!!

[@edwardneilander6427]

Great Video, love the insight and detail. The shorts at the end are great!

[@AZExpert]

Much appreciated!

[@Chris_In_Texas]

Quick fix, use EFI. I guess I have been spoiled with all the marine generators that I have owned have been EFI based units both gas and diesel, from 5KW up to 32KW. Seem as compact and hard to get to as most marine units as well, especially when they put them in sound shield boxes. Great job sir. 🤠👍

[@AZExpert]

Thanks for the tip

[@myk55501]

Hey here a tip Permatex® High Tack® Spray-A-Gasket® Sealant, it will hold the gasket on making it easier.

[@AZExpert]

Great tip! I'm leery to spray on the carb surfaces and clogging orifices and it's a tight fit so often the gasket gets damaged when held onto the surfaces.

[@myk55501]

@@AZExpert they have brush on too but i use towel plug hole or spray gasket it self away from part. Using it for years no problems yeat. Lol. I makes the job easier and faster.

[@gereshomeE]

You REALLY know your stuff! WELL DONE! ☺

[@AZExpert]

Sometimes :)

[@badgerpa9]

Surprised they do not have a crush washer on the drain plug, but using a little pipe dope is better than teflon tape getting in the oil, especially with no oil filter. Stay safe and healthy.

[@AZExpert]

I mostly did that because I know I would hear about it ENDLESSLY lol

[@MililaniJag]

WOW! OEM carb IS expensive! Great info!

[@AZExpert]

It really is! but worth it in my opinion

[@cavemanmaine1314]

I had a 99 Brave with one of these 4000 quiet onan and it was brand new.After running for about 15 minutes it would start to surge and then die.It was closeing up the gap on spark plug.Open up gap and it would start rite back up.

[@gdejackmo]

One word for those gaskets... Permatex High Tack Gasket Sealant. It's a Gasket dressing you apply to the mating metal. Your Gasket will stick to the mating surface so you can assemble with ease!!!!

[@rlmc29er]

Great video on the Gen maintenance. I have one of these to do tomorrow. Thanks for your videos.

[@clydedenny8661]

I know the grounding wire for the carb solenoid has a screw that goes into the chassis, but I found it strange that you didn't place the lead behind the painted surface of the starter housing. other than that trial piece, I really appreciate your explanations on how to do things.

[@Imwright720]

My generator is from 2006. I’ve always run it dry. A few days ago it started doing what yours is. I took mine apart and it was perfect. I kid you not it looked perfect. The surging is still there but mine has an electronic governor. It needs 12 volts to work properly and is only getting 10.5-11. It’s not always the carb

[@AZExpert]

Thanks for the comment

[@Rotormansa]

Great video with awesome details. My gen is the same except the air filter bracket is broken. I thought I'd be able to replace it myself but..... all the gasket alignment could be challenging. If you are just replacing the el-cheapo bracket for the air filter would have to replace the carb gaskets. My hope is the existing gaskets would stay in place and just have to remove the bolts and broken bracket with a new bracket. If not, then it's off to someone with better dexterity than me.

[@spoolin55psi]

I guess that’s why the Rv I got didn’t have a control board. The owner knew it needed a part that was expensive but didn’t know what it was. Now at least I do

[@jebediahkerman3946]

One of the most common failures on onan generators is overfilling the oil. If your generator has problems running for 10 or 20 minutes then dying, make sure the oil level is just above the low mark on the dipstick then try again. This is a very common issue that Onan apparently can't seem to diagnose themselves.

[@RobertSmith-wb3qv]

Why do they say must run the generator once a month(?) the Gas will dry out of the carb. and the fuel pump will not operate with the engine not running one must disconnect the fuel pump wire run it to a twelve volt and fill the carb. first.

[@craigjohnson3603]

Good video, I use old fashioned carb dip solution and have good luck with that. But I see your point about liability anything can fail. I had an old 1972 Winnie with a Onan 4k that I replaced brushes in so I found out what a pain they can be to work on!

[@daniellebenjamin2971]

My generator hasn't been run in years (long story short: my brother was borrowing the RV, got hurt, was in the hospital and now generally immobile). I'm flying to him so I can pick it up in a couple weeks. I live in Texas... I hope I can get it working or I'm sure to melt.

[@daniellebenjamin2971]

Hey.... any tips for diagnosing the problem? You think I should I start by just replacing the carburetor.... I imagine it's all gunked up.

[@itchntohitch4143]

More thanks coming right at you! You are a treasure.

[@richb4099]

If you put the wingnut and air filter lid back on after removing the carb bolts, the carb comes off easy. I glue the gaskets in place. Those carbs are over $400 now. I've tried the Chinese knockoffs but they may or may not work. I had 1 out of the last 3 that actually worked. Last time I tried them, 2 went in the garbage....A used Onan ran fine.......If you would have removed the black limiter cap on the "altitude" adjustment and richened it up 1/2 to 1 turn the surging would likely stop.......That is the main mixture adjustment, needle valve.....The throttle shaft also gets worn sometimes and the carb does need to be replaced...

[@hindegarrison970]

Thanks for your videos! This one has been super helpful. We do our own generator maintenance on the gas-powered micro-lite 4K on our 1995 Coachmen Santara QB280. Ran into an issue two weeks ago that still has us flummoxed. The U-shaped bracket for the air filter that is attached to the frame of the generator (to which the cap holding the filter screws) fell off. While the generator was running! What do we do to reattach it? Seems a bit beyond "bondo..." Tack weld it back into place? Anyone else had this happen?

[@ShayanAhmed-w5y]

STRONG WORK WITH HUMBLE

[@thecemeteryguy]

I thank you for all your shares, your awesome.

[@AZExpert]

Thanks!!! I appreciate that

[@rvmonkey1669]

Super glue is your friend with these gaskets makes life happy

[@AZExpert]

Unless you have to take it off again?

[@rvmonkey1669]

@@AZExpert Just two dots on each gasket

[@TimothyMichaels]

I have the Onan 6300, propane. Won't start, propane full, steps won't work unless I start the coach. Heart interface inverter panel is dead. Worked when I first bought it a few weeks ago. Plugged in at Quartzsite AZ RV park, so I guess not needed at the moment.

[@mikeinsanediego]

No truer words have been spoken...."whatever you do dont hit the switch with the oil cap off, it will splash you in the face" yep...been there.

[@AZExpert]

I speak from experience

[@haroldyoungblood8287]

If you use startron every time you fill up and you will not have varnish build up. Never ever. I used stabil for years but seemed to have rubber breakdown issues. I have rebuilt or cleaned hundreds of carbs. Use Berryman carb cleaner, disassemble carb completely, blow all jet passages with high pressure air. In my life time I only found one carb on a high pressure washer that wouldn’t tune after a cleaning. Spraying carb cleaner on a dirty carb won’t always fix your problems. Weed eater type like Waldon, I get it. You can’t find kits like you use to.

[@yyl3683]

Excellent work and excellent video as always

[@AZExpert]

Thanks!

[@BillLadd-s8d]

Great video content James! I just did a tune up on my 1995 Winnebago including spark plug. The oil was nasty black like it had not been changed in years! It has white smoke until it warms up. Was thinking of trying some Lucas leak stop! Do you have any suggestions for possible leaking valve seals?

[@ku567318]

how many times have I commented on this video, BUT, thank you again.

[@daviscrt]

Great informational video. Thanks again Don

[@AZExpert]

You are very welcome

[@caryrodriguez7040]

Very informative, thanks James! 👍

[@somchaiwongma3813]

If you fill the oil all the way to the top of the filler neck you overfilled it. If you had shown the oil dipstick after screwing it all the way in, it would have been clear that the oil level was way over the MAX mark. The correct level is somewhere at the bottom of the filling neck.

[@NackDSP]

That generator is the biggest head ache on my RV. Some folks on youTube claim that if you put more than the 1.5 liters of oil in, the generator will stop on hot days. I'm careful to measure out the oil. It's also 21 ft-lbs torque on the drain plug. Measure and you don't need to wonder if it will work. It's a shame they don't install generators with fuel injection and an inverter in these RV's. I may pull out this 175 lb monster and replace it with six solar panels and a bunch of LFE batteries. For the $4,000 they get for this generator, I could buy lots of panels and batteries.

[@AZExpert]

I agree. There are some fuel injected emerald series now, but yeah, for $4000, these should never have issues like this.

[@MaryWehmeier]

Ours has had surge issues too. And the price here in LA is more than $4k. 🤦‍♀️

[@nickvallerga1411]

We purchased our Sunseeker new, Onan QG4000 had 2 hours on it. Did a oil change at about 30 hours and 70 hours. Around 90 hours while were out camping I could not get the gen started, I ended up using my EU2000. Once I got home I decided to change the spark plug and air filter. I found the plug black and fouled. I could not understand why the plug fouled, I always set the proper altitude on the carb. So I ended up putting in a one step hotter NGK plug and it ran fine. At 100 hours I decided to do another oil change and found the oil level only 1/4 up the hashtag on the dipstick after 30 hours. I know when I had changed it before I filled it to the top of the hashtag, so this told me that it is burning oil and fouling the plug. I do keep a spare plug on board now. Looking at the RV forums this appears to be a common problem with these. So I'm trying a "break-in" procedure to see if oil consumption improves. I've been running it at near max load for one hour for several days, and then I'll check the oil level after 30 hours. Has anyone else had oil usage issues with these also?

[@MagaRickn]

Dang, sure wish you were closer to Ft. Worth! :)

[@AZExpert]

I've been through Texas enough this year LOL

[@rickhodges1731]

Overall another successful restoration. Took two wrecks to make one good one. 👍 Still think it looks like a giant refrigerator or a delivery van. Accent stripping would make big positive improvement to the coaches exterior appearance.

[@AZExpert]

Not my coach

[@rickhodges1731]

@@AZExpert Ops was intended for the Niko Brothers channel. Sorry about that!

[@wickblackwell5218]

Great job. Love watching.

[@davidmcgee2126]

Like your videos I would have hit it with some air and brake cleaner to get rid of some crud before tearing down I would have tried seafoam before replacing. I find it works more often than not. Just have to let sit overnight

[@DaveGray-j7q]

I've rebuilt hundreds of mower and motorcycle carbs. I'm pretty sure I'm trying that before spending 400 bucks on a new one.

[@alanbolla8443]

Wow!! now I have to check mine for that drain plug on the under side, I've had to pump the oil out to change!!!🤔🤔

[@AZExpert]

It's sneaky

[@Robert-u3w]

Great video

[@twylabowman4247]

Thank you for this video. Very helpful. I have the same generator and just replaced the carb, fuel filter and pump as well as the spark plug and air filter. I even changed the oil. I was so excited to fire it up….When I did, there was a fuel leak due to a faulty, Chinese filter. I replaced it the an Onan filter and when I went to start it ….NOTHING. In the process of testing it out, I turned on the air to put it under a load and that’s when it started surging. I must have thrown the Manuel breaker because everything else checks out fine. My problem is that I can’t locate the manual breaker. If anyone has a clue, I’d surely appreciate it. I have an 04 Tioga class C

[@brentmcmahon8188]

Just a question for you I have a 10.6 Bigfoot truck camper and ran my exhaust pipe all the way up past my roof a little bit and it has a slash at top to point the opening towards the back because I didn’t want to hear it or smell and it works great but a tiny bit of straight pipe sound and if my wife complains I may have to put a small muffler 3/4 the way up but I like the sounds it makes. When we get 3/4 of the way to where we are going to stop . I start the generator and AC to get it cooled down so when get inside it’s nice and cool inside and my 2500 Onan is run on propane and the only thing that happens is if is 2 table spoons of oil is just enough to let it start and motor slings oil all up in the motor and it will die. And it always happens when we are at a camp ground and some one will say how cool that is that my exhaust is above my roof and I tell them you can not point them straight up and blow soot water and tiny bit of gas and it will blow that stuff all over your camper and then somebody will ask me about their generator and 99 % of the time they are low on oil and I alway fill it at top oil full line and when they start their genset starts and stays running and then they say how much they spent at shops trying to fix it and the tec always says the same if that doesn’t do it you will have to find a Onan repair shop and the guy I bought it from then try to tell me they drained and fill it with synthetic oil and bugs all over the front of camper and I don’t think he did one thing right. He had duck tape on a crack on the cover for roof top ac and I camper lot that does alot of repairs and the parts gal me 90 bucks for cover and 90 shipping and the front happy Jack on drivers side was wrapped with duck tape because the manual socket would fall out. I got on Amazon AC was 90 bucks with free shipping and the happy Jack was a 15 cent C clip some people are so cheap and would not fix it or didn’t know how and both rear happy jacks was pulled lose from camper so I drilled the plate to the next size bigger lag bolts and I dipped the tip of each lag bolt wit a tiny bit West Marine and it is solid as a rock but if we go to Alaska I will take all four jacks of and roll them up in a piece of carpet,somebody doest hit them or me going threw a dip and there only 3-4 nuts to take them off and unplug the and screw cover back on. I seen a guy do that and said that’s a good ideal .

[@jamesisbrandt2855]

Will you come out to Mobile, Alabama and work on MY generator ? You look very confident and knowledgeable.

[@lindanadaud9698]

Thank you for the video.

[@AZExpert]

Thanks for watching!

[@jimmethven8074]

The generator runs fine but the gen breaker keeps tripping. As soon as it's up to speed it trips. No codes. Can't find a short anywhere. Shore power is fine, with no issues. Suggestions?

[@brentmcmahon8188]

I sure wish Oman would up date their stuff like smart throttle and fuel injection like Honda and it only adds gas to match the load and the number one thing that I tell people when camping ? Did you change your oil before this trip and they almost always say yes and I ask them does it start and die and I tell them your low on oil and my best advice is to fill your oil to the high mark and they fire right up .

[@alanthompson7674]

Thanks so much for what you do for all of us viewers! Love your stuff.

[@AZExpert]

sneaky how they cover it up

[@artbentley4887]

Hello, I have an older Kohler 4500watt. My start stop switch went bad so I removed it and left the wires disconnected and put in a key switch and now I don’t have any power from the generator. Does this need voltage for the exciter in order to have power!! It starts and runs great but no power. Thanks

[@wildstringdom]

Hey just wondering if you've heard of some of these not having the fuel drain screw that you were talking about my carburetor does not have that so I could not find anywhere to drain my gas from the carburetor and i'm frustrated

[@TracyHaynes-z2h]

I am trying to find out how to adjust a float because in my generator which I have a I have a McGraw Edison on in 6.5 RV genset and I need to adjust the float in the carburetor and I need to know how to do it

[@brentmcmahon8188]

I’ve broke fittings with Teflon tape , so I kinda stick with pipe dope.

[@EdwardBonnieSimonson]

Watching you do this looks easy. But I am no mechanic. My problem is the generator runs great for all appliances until I turn the Air conditioner on then the generator just sputters out and dies. Any tips? Great video here and I have subscribed to your KZbin channel to learn more and follow you. Thank you.

[@coreybabcock2023]

I actually run e15 u88 in my wen 3800 and not a issue yet but they'd cause I run it all the time so yes it does keep it clean and running well

[@AZExpert]

Awesome!

[@coreybabcock2023]

@@AZExpert definitely

[@rowdyrowboat]

to help with the gasket install use some dabs of indian head shellack. it will bond the gasket to the carb and the plastic plenum to the gasket.

[@robertanthony2015]

Any clue why my RV QG 400 would have oil on the air cleaner cover, control board, solenoid and battery cable? I did find a very small drip at the bottom of the head cover gasket right above the oil fill but the left side away from the engine is very oily. Thank you in advance

[@jamiegoroski9409]

So I have an onan 4000 gensst no spark. I replaced the coil, module, rotor and circuit board. Still no spark. Turns over but no spark. I'm running.g out of hair to pull out do you have anything on that?? I'd really appreciate any kind of help. Thank you!

[@janetcraft6339]

I need help not on generator, I have followed all your kiwee steps instructions but mine still I purchase a new part someone helped from rv place in Columbia he did wires now nothing they are bungee now.help

[@lutomson3496]

Add seafood to fuel helps the engine and generator to start with never had a problem and I do the same with my diesel with additives for my engine and generator and running them is important

[@AZExpert]

I know you meant Seafoam. I'm assuming you arent adding in shrimp to your tank. :D