Onan Generator 4000

Just had my Onan 4k repaired for $700 and change here in Chicago. They quoted a few hours each to remove and reinstall at similar labor rates and great professional service, but $1900 seems pretty high. I know this is an older thread but wanted to share in case anyone needs a referral... Message me.

Bordercollie wrote:
I have gotten estimates of $300 (many years ago) to remove genset, troubleshoot it on the bench and reinstall it.

This is TOO much of a difference.
Are you sure we are all talking about the same model of RV here ??

Some are mounted on rails even for easy servicing.
Mine looks like it would fall out on the ground if 6 or so bolts were removed.
Apparently some are much more complicated than that.

OR the OP has found a dishonest Cummins dealer.

I have gotten estimates of $300 (many years ago) to remove genset, troubleshoot it on the bench and reinstall it. After that, parts and labor as needed. Once they have it out, you will be charged for the removal and replacement regardless of whether you give go ahead for the fix. It's too late to shop around for a better price. If you can find an independent generator shop, you might get fixed much cheaper.

That's crazy expensive it's really not that hard you can loosen the shroud and partially lower the generator to change the starter

WOW. That sucker must be BURIED deeper than a well digger's behind.

At $100 per hour, that is about 13 hours labor.....just to remove and re-mount the unit ???

Sure sounds high to me but if it is that complicated I certainly would NOT trust the "mechanics" at CW to take a shot at it.

Ok I can now report the update.I took the RV to Cummins in Glen Burnie,MD.They called me following day that it seems starter is bad and Generator has to be taken down from the RV and they will call me if there are any other issues.I received the call 2 days later that it will cost me 1900 dollar for the repair which include servicing the Gen,replacing the starter,oil/filter change and putting it back.I was surprised with the cost of repair but they say it is mostly labour for taking it down and putting it back.Finally after much argument bill was settled at 1558 dollars of which 1330 dollar was jut labour.Is this usually the cost for Onan Gen 4000 repair cost or could it be lower if I would have taken it to camping world.

Be sure-fire-certain your coach's House (not Starting) Battery is good. Actually Good with Capital "G" Those gensets are really fussy about the battery. It'll seem good for everything else you ask it to do and won't crank the genny.

By all means, check connections, and be sure the cable ends aren't corroded WITHIN their terminals.

But if that battery's marginal, the genny will call you out on it!

Droptop351 wrote:
Had this exact problem this week. All of the answers above could be correct, low voltage, bad solenoid or starter, bad cable connections.

Mine was stupid thing turned off on compression stroke so I took a 9/16 wrench and turned flywheel and loosened it up. Started right up

If you want to rule this out take the spark plug out and hit the start button if it don't turn over and just clicks then it's one of the 3 listed above

Most small engines will come to a stop at the compression stroke, since that's where the friction/force is greatest in stopping the flywheel's rotation. The starter should be able to kick it over the compression stroke without trouble; if it can't, then either there's a bad connection or battery (so it's not getting full power) or the starter is at least partly faulty.

I had a starter that was barely able, on a good day, to overcome the first compression stroke. I eventually burned it out trying to start it on a not so good day. Upon inspection after replacement, I discovered that one of the four brushes had become disconnected, which explained the initial low starting power, as well as having one or two of the coils burned out (the final death blow).

These starters, unlike many electric motors, have four brushes and hence two pairs of magnetic poles around the rotor. If one of the four brushes is not making connection, it will still turn, just at half power. Unfortunately for people like me who need to replace the starter, it's located on the back side of the engine and is not accessible without dropping the generator and removing the outer cover entirely (not just the maintenance hatch), which makes it a rather laborious task to get to the point of replacement.

Had this exact problem this week. All of the answers above could be correct, low voltage, bad solenoid or starter, bad cable connections.

Mine was stupid thing turned off on compression stroke so I took a 9/16 wrench and turned flywheel and loosened it up. Started right up

If you want to rule this out take the spark plug out and hit the start button if it don't turn over and just clicks then it's one of the 3 listed above

When I run into this problem I start the motorhome engine and while it is running I can start the generator. That is because the alternator is providing power to both the house and chassis batteries. If the generator starts then you can pretty much rule out a problem with the starter or its solenoid and concentrate on the battery and cable connections.
Good luck!