Onan 4000 Gen Set Service

[jands]

If I take my coach to have the Onan 4000 Gen Set serviced, what work can I expect to be done?

Thank you in advance!

[Chateau_Nomad]

Originally Posted by jands

If I take my coach to have the Onan 4000 Gen Set serviced, what work can I expect to be done?

Thank you in advance!

Depends on the hours... about the only thing I wouldn't do myself is valve lash adjustment. And that's a LONG time down the road.

Look up the service manual for your model. It tells you exactly what should be done and when.

[Muggs]

Easy oil change see youtube. Air filter check/replacement no difficult.

One of my buddies paid $150 for gen oil change and grease e450 front end.

[MJC62]

Depends on the hours on the genny as the Nomad said. At a minimum the oil changed & inspect the air filter.
I purchased the Onan tune up kit from Amazoon if I remember it was around $45 for Onan OEM parts. Air & fuel filters & spark plug. A little salty IMO but genuine Onan parts. Bought the synthetic oil at O'Henry's Auto Parts. An hour an a half on a nice day and the Genny is ready for a season.

[CRFTN]

Hi.
I hope its ok to ask a slightly off-topic question about the generator.
My new to me 2017 Thor Vegas has the Onan 4000btu generator also, and I can't get a good reading on the dipstick. The dealer I bought it from claims they replaced the oil, but a week ago when checking the level, there was NO oil on the dipstick. It may be that the RV has to be really level to get an accurate reading?
Thanks in advance,
Chris

[EA37TS]

Originally Posted by CRFTN

Hi.
I hope its ok to ask a slightly off-topic question about the generator.
My new to me 2017 Thor Vegas has the Onan 4000btu generator also, and I can't get a good reading on the dipstick. The dealer I bought it from claims they replaced the oil, but a week ago when checking the level, there was NO oil on the dipstick. It may be that the RV has to be really level to get an accurate reading?
Thanks in advance,
Chris

If it were me I would first verify you have the correct dipstick. I would then add oil to see if it shows and if not I would then drain the oil and add the amount specified in the gen specs.

[Chateau_Nomad]

You probably have a yellow threaded oil cap with a short integrated dipstick.

Be sure your RV is level. Run the engine until warm. Shut off and wait about 15 minutes. Thor does not require the dipstick to be threaded in when checking the oil.

If the oil isn't between the full and add marks, either drain or add oil. If there is NO OIL showing on the dipstick at all - it is LOW.

I suggest NOT trusting a dealer with checking oil level... DO IT YOURSELF... then you KNOW it's correct.

[16ACE27]

I just changed the oil on my generator today. I used 10w-40 synthetic and it was very clear and hard to see the level on the dipstick. And yeah - make sure the MH is level.

[CRFTN]

Thanks for the quick replies! The dipstick is yellow, and I tried to find a flat parking lot to then check the level again, but it still didn't even register on the stick. I started adding oil to see if I could get a reading, but still barely showing. I'll verify a truly flat spot to check again. If it's like my 150hp Yamaha outboard, the tilt of the engine can be changed by just a few degrees and the oil level reading will be way off.
I appreciate the help!

[abjbrtd]

Originally Posted by CRFTN

Hi.
I hope its ok to ask a slightly off-topic question about the generator.
My new to me 2017 Thor Vegas has the Onan 4000btu generator also, and I can't get a good reading on the dipstick. The dealer I bought it from claims they replaced the oil, but a week ago when checking the level, there was NO oil on the dipstick. It may be that the RV has to be really level to get an accurate reading?
Thanks in advance,
Chris

you would NOT be the first victim of the high school dropout that drained the oil then went for a smoke, and started another oil change

OR be the buyer of a certified BMW that the same dropout forgot to DRAIN the used oil but remembered to change the filter and put new oil in.
I can't believe I didn't at least pull the dip stick, take the radiator cap off etc etc before diving our new to us " Certified" BMW 30 miles home

PLEASE MAKE SURE THERE IS OIL in your generator BEFOR TRYING to start it!

[Chateau_Nomad]

Originally Posted by abjbrtd

you would NOT be the first victim of the high school dropout that drained the oil then went for a smoke, and started another oil change

OR be the buyer of a certified BMW that the same dropout forgot to DRAIN the used oil but remembered to change the filter and put new oil in.
I can't believe I didn't at least pull the dip stick, take the radiator cap off etc etc before diving our new to us " Certified" BMW 30 miles home

PLEASE MAKE SURE THERE IS OIL in your generator BEFOR TRYING to start it!

100% AGREE!! Me? I'd keep adding oil until it shows on the dipstick!! Otherwise... THE OIL IS LOW!! Don't ASS.U.ME. Even if you over fill it, you will KNOW where the oil level is! Then just drain a little out.

[Pete'sMH]

It only uses about a quart and a half. If it was mine I’d pull the drain plug and see what comes out. Then put in the correct amount. It’ll only cost a few bucks and the. You’ll know.

[Chateau_Nomad]

Originally Posted by Pete'sMH

It only uses about a quart and a half. If it was mine I’d pull the drain plug and see what comes out. Then put in the correct amount. It’ll only cost a few bucks and the. You’ll know.

AGREE!! This is even better!!

[Scubawise]

Originally Posted by Pete'sMH

It only uses about a quart and a half. If it was mine I’d pull the drain plug and see what comes out. Then put in the correct amount. It’ll only cost a few bucks and the. You’ll know.

Agree 100%

[paulwadley]

The oil is a cheap insurance to be sure it is correct by doing it yourself. It is an easy job and then you know for sure it is done right.


Paul

[z28]

Originally Posted by Chateau_Nomad

Depends on the hours... about the only thing I wouldn't do myself is valve lash adjustment. And that's a LONG time down the road.

Look up the service manual for your model. It tells you exactly what should be done and when.

They will drain and flush your wallet. Do it yourself it's really not that difficult, just keep food records and use the correct products.

[Scubawise]

Originally Posted by paulwadley

The oil is a cheap insurance to be sure it is correct by doing it yourself. It is an easy job and then you know for sure it is done right.


Paul

It is easy....folks here helped and see youtube

[Chateau_Nomad]

It's so easy... I might have my 3 year old grandson watch/help me in a couple weeks when I change ours for the winter hibernation. He loves anything mechanical! Nothing wrong starting him early!

[71_340]

Originally Posted by Chateau_Nomad

You probably have a yellow threaded oil cap with a short integrated dipstick.

Be sure your RV is level. Run the engine until warm. Shut off and wait about 15 minutes. Thor does not require the dipstick to be threaded in when checking the oil.

If the oil isn't between the full and add marks, either drain or add oil. If there is NO OIL showing on the dipstick at all - it is LOW.

I suggest NOT trusting a dealer with checking oil level... DO IT YOURSELF... then you KNOW it's correct.

My Onan manual states to screw the oil filler cap in to check. Obviously your coach has to be perfectly level to get an accurate reading.

[Chateau_Nomad]

To be clear... it doesn't state to thread it. It just says to insert it into the filler tube.

Odd... on all my small engine power equipment (lawnmowers, tiller, etc.) I've always threaded, but Onan doesn't specify that in mine...

EDIT: Here is copied text from my Onan manual. Now... you tell me exactly what they're trying to say here. Looks like either a typo, or a contradiction!

1. Unscrew the oil fill cap and pull out the dipstick.
2. Wipe off the dipstick and thread back into the fill neck.
3. Reinsert the dipstick and remove it again to check oil level.
4. Add or drain oil as necessary. Keep the oil level between the full and add marks.

I think threading is the correct procedure...