Replacing Onan Generator

Cherry T

Member
Joined
Jan 4, 2017
Messages
23
Location
Myrtle Beach
We routinely have our generator serviced between trips. When we set out on our last trip it would not start and had an error code. When we returned home we took it in for a delayed front end AC repair and to have the generator checked out. Per the mechanic he has tried several things and cannot get it to work. He thinks it needs to be replaced.

Problem per him and Camping world - they are hard to get.

DH is checking with the mechanic to find out how long it will take to get a replacement. Otherwise, we are considering upending our trip and visiting Elkhart at the start of the trip. If it is something that can be replaced there.

Any recent Thor ACE owners faced with the same issue?
 
We routinely have our generator serviced between trips. When we set out on our last trip it would not start and had an error code. When we returned home we took it in for a delayed front end AC repair and to have the generator checked out. Per the mechanic he has tried several things and cannot get it to work. He thinks it needs to be replaced.

Problem per him and Camping world - they are hard to get.

DH is checking with the mechanic to find out how long it will take to get a replacement. Otherwise, we are considering upending our trip and visiting Elkhart at the start of the trip. If it is something that can be replaced there.

Any recent Thor ACE owners faced with the same issue?
I hate generators- dirty (stinky), noisy, high maintenance, and PITA in general.
Add to that the restrictions at the campgrounds when you can operate them, and are 40X more polluting than the chassis engine. So the under-hood generator is perfect in that respect, and chassis engine is a lot quieter anyways.

I removed the Onan from my Rialta and installed 414Ah of lithium right where the generator used to be, with 3000W inverter inside, and never regretted it. I could go 2-3 days w/o plugging in.

Now with the 2022 Tellaro w/ under-hood generator, I replaced the 200Ah LFP batteries with 600Ah and now can go 5+ days w/o starting the engine or plugging in.
I rarely stay more than 3 nights at any given spot, and driving recharges the coach batteries.
On our last trip to Utah, I boondocked the whole time- no plugging in or running the UHG- all solar (380W) and battery power. Use the Microwave 2X/day or toaster, and propane heat. No problems. Off-grid rolling house!
 
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I doubt that your generator can’t be repaired. Find a Cummins/Onan service center and take it to them for a second opinion/fix.

Mine wouldn’t start and I took it to the Albany, NY Cummins/Onan service center. They replaced a circuit board and all was fine.

If you really do want to replace it, go with Onan’s new 4000i inverter model. It’s only a few hundred bucks more expensive and is more efficient and quieter. Norwall says that they can ship in 3-4 weeks. See https://norwall.com/products/cummins-onan-rv-qg-4000i-evap-gasoline-40hglba-8306a

There is another brand that is inverter based and may or may not be better than the Onan. See https://rvmp.co/collections/rv-generators

David
 
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Agree with David... find an authorized Cummins service center. Sounds like you found a "mechanic" who isn't familiar with Cummins generators... or just wants to take the easy path. I imagine if your mechanic was paying the bill it would be a different diagnosis! :LOL:
 
I'll third the Onan/Cummins dealer advice from above. A problematic generator is not an ACE problem, a Thor problem or any other RV manufacturer problem - they are in every brand RV - take it to the generator experts for diagnosis and repair.
 
Cut to the chase.
Your mechanic hasn't a single idea what he is doing.
Do not proceed, find another.
He seals his fate by not telling you if it's mechanical or electrical.

To replace my gq4000 generator the total bill was $9500+.
My extended warranty(that came with my rv) paid for all but $100 of it.

My problem was simply a small brass shaft broken off of the choke was holding open the exhaust valve. It would not start.
The mechanic could have fixed it by just removing the head and getting a new $50ish carb or a $4 choke part.
I kept the old generator and bought the $30 head gasket.
My d one works perfectly and now lives on a pallet as a spare.

Your problem may be as slight.

And
Did you look on line to see if your model generator is available and they even bothered to look?
 
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I think some folks are reading way too much into my original post.

He tried several things, found the problem and explained what is not working and what it would require to repair the problem.
 
Perhaps we're not able to read too much into it.

Your generator has nothing specific to do with ace.

Since you know what's wrong and haven't told us, we're not even sure what your question is.

Of course others have had broken generators.

'He thinks' is not a diagnosis.
He's about to poke you for $9500...solely on a speculation.

Weigh what we ALL said about your mechanic.
 
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We routinely have our generator serviced between trips. When we set out on our last trip it would not start and had an error code. When we returned home we took it in for a delayed front end AC repair and to have the generator checked out. Per the mechanic he has tried several things and cannot get it to work. He thinks it needs to be replaced.

Problem per him and Camping world - they are hard to get.

DH is checking with the mechanic to find out how long it will take to get a replacement. Otherwise, we are considering upending our trip and visiting Elkhart at the start of the trip. If it is something that can be replaced there.

Any recent Thor ACE owners faced with the same issue?
Please make an appt and go to Onan.
They gave me an extra 2 years.
4 years zero running issues
 
We routinely have our generator serviced between trips. When we set out on our last trip it would not start and had an error code. When we returned home we took it in for a delayed front end AC repair and to have the generator checked out. Per the mechanic he has tried several things and cannot get it to work. He thinks it needs to be replaced.

Problem per him and Camping world - they are hard to get.

DH is checking with the mechanic to find out how long it will take to get a replacement. Otherwise, we are considering upending our trip and visiting Elkhart at the start of the trip. If it is something that can be replaced there.

Any recent Thor ACE owners faced with the same issue?

:peace:

Take a deep breath. You came to this forum for a reason. Follow your instinct, listen to what it is being said, don't assume your mechanic or Camping World is right.

Not to agitate, but the questions are to get more insight, the better the information the better your answers. Think being at Doctor's office to diagnose pain in a shoulder, the number of question may seem irrelevant to you, but for the experts all the answers helps with a better diagnosis.

When I 1st read your thread, I wondered why you would routinely have your generator serviced in between trips? What type of service was done in between these trips?

The 2nd thing is you did not say what model Onan, how old is it, and how many hours?

The 3rd thing was when it was being serviced, have you been using different mechanics each time? 4 Chefs are asked to make a Lemon Frosted Chocolate cake and you get 4 different ways of baking the cake.

My comments and views.

A properly serviced Onan will never have any issues. Other than brand new they only need service once ever 150 hours of usage. I service mine once a year, but that is on a convenient schedule for me.

Onan extended my warranty out additional 2 years just because I had an Onan Authorized Dealer install my Onan EC-30 AGS. I have spoken with Onan Engineering and they insist the #1 issue or cause of failures in Onan Generator is lack of use. I run mine for every possible thing I can think of and still can only get about 120 hours / year. i.e. in the summer I drive with my Genny running.

Please follow the advice above. Call Onan directly, tell them your story, they will direct you to Authorized dealer.

I for one would love to know what Onan says. I can almost guarantee you that they will NOT say it needs to replaced if it has been properly serviced as you suggest. They make the things, and would love for you to buy another one, but your genny is an Engineering wonder. They will run test to find out exactly why it does not start and get that fixed.

When fixed you can take the $8k - $9k that you may save and buy something else that you and your family would enjoy.
 
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Mine wouldn't start after sitting unused for several months. It's a gasoline unit, Onan 4 Kw. The gas tank had fuel stabilizer. I took it to a mechanic who works on these a lot. He removed the carburetor, disassembled it, cleaned everything thoroughly, and put it back together, for about $400. Definitely a job for someone with experience. Works like a charm now. Now I make sure to start it, along with all the propane devices (frig, water heater, furnace), once every week or two, and everything fires right up.
 
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Our 4k Onan seized about 18 months ago and a replacement was stated to be 12-18 months out. Did some research and found a unit that would ship in 1-2 weeks, was built to replace the Onan, runs on gas or propane, provides more power, less noise and costs less, only $3588 at the time. Our RV tech had no issues changing it out and we have had zero problems with it so far, one of the hidden pluses is when the card starts getting gummed up on gas, hook an LPG hose to it and it cleans everything out.

Here is the company we purchased it from... AP Electric & Generators LLC
https://apelectric.com/

and here is the Item Info: RVMP 4000i Flex Power 4000W Dual Fuel RV Generator RVMP-AM-4L1-RV401
 
https://www.amazon.com/gp/aw/d/B07K7BC1CZ?psc=1&ref=ppx_pop_mob_b_asin_image

https://www.amazon.com/140-3280-Fil...09-b074-29ad1225c57d&pd_rd_i=B01M759L7W&psc=1

https://www.amazon.com/Generators-r...38-9a42-2fed646739d0&pd_rd_i=B07C4PZ34G&psc=1

Under 70 bucks for carb, airfilter, fuel filter combined.

You might have been abused.
It's a 30 minute install if it's not your first time seeing that model generator.
My first time took almost an hour.

Cleaning that carb was a lot of useless labor.

So let me see if I follow these points.

I can spend $9,500 to follow what a mechanic & camping world says, or I can pay $70 to rebuild, or I can follow the Onan instructions verbatim running and exercising as prescribed for free :rolleyes:

Wow this is hard, let me get back to you.

If every time a Onan generator thread was created, and if everyone went outside and ran their generator for 1 hour & serviced every 150 hours there would be no more generator issues :coolsmiley:
 
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Take your generator to a certified Cummins Onan service facility. I would not trust, and do not trust Camping World to perform any type of repair!! Sorry I've been burned by them enough!
 
It is silly to let the guy who didn't apply the dicor correctly before lunch
to work on your generator after lunch.

Once warranty ends there is no reason to ever step back into a do-it-all dealer type shop. Find an oil shop, find a cabinet shop, find an ac shop, find a stereo shop, find an electrician. Find a handyman.

Look where my spare air filter lives.
The oil for the 10 minute oil change lives just above it.
A quart, a pint, and half a cup puts you about a tablespoon within the 1.6quarts booked.

And
Look it up:
The dipstick readings are wrong on many qg4000 by about an ounce.
Close is good enough on these size/type engines.

I'm not advocating DIY. Tell your tech how much oil it takes and show him where the spare air filter is.
 

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Take your generator to a certified Cummins Onan service facility. I would not trust, and do not trust Camping World to perform any type of repair!! Sorry I've been burned by them enough!

Amen. Did same.
Onan extended warranty
 
It is silly to let the guy who didn't apply the dicor correctly before lunch
to work on your generator after lunch.

Once warranty ends there is no reason to ever step back into a do-it-all dealer type shop. Fi d an o shop, find a ca inet shop, find an ac shop, find a stereo shop, find an electrician. Find a handyman.

Look where my spare air filter lives.
The oil for the 10 minute oil change lives just above it.
A quart, a pint, and half a cup puts you about a tablespoon within the 1.6quarts booked.

And
Look it up:
The dipstick readings are wrong on many qg4000 by about an ounce.
Close is good enough on these size/type engines.

I'm not advocating DIY. Tell your tech how much oil it takes and show him where the spare air filter is.

Genius
 
It is silly to let the guy who didn't apply the dicor correctly before lunch
to work on your generator after lunch.

Once warranty ends there is no reason to ever step back into a do-it-all dealer type shop. Find an oil shop, find a cabinet shop, find an ac shop, find a stereo shop, find an electrician. Find a handyman.

Look where my spare air filter lives.
The oil for the 10 minute oil change lives just above it.
A quart, a pint, and half a cup puts you about a tablespoon within the 1.6quarts booked.

And
Look it up:
The dipstick readings are wrong on many qg4000 by about an ounce.
Close is good enough on these size/type engines.

I'm not advocating DIY. Tell your tech how much oil it takes and show him where the spare air filter is.

If it ever stops raining and I get some time I am gonna create a new thread where I clean and service my Onan 5500. It is at the 5 year milestone and just purrs away. It powered the house last week during power outage when 80 mph winds came out of no where and hit Dallas. Firing up the Onan Generator and my EC-30 AGS is still my favorite part of the RV experience. If it was not for the weight issue, I could put a saltwater tank in the RV knowing I could always have power as needed to maintain the water temperature for delicate fish :rolleyes:
 

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