Onan 2800 starter problem

[Brital]

I have a 2003 Leisure travel van with an Onan2800 generator
Suddenly the starter seems to have seized.
I get a "clunk" noise and the lights dim when I press the starter even on shore power and when the engine is running.
I suspected a loose ground but the connections at the battery are OK. I do not know how to access the battery wires where they go into the generator as it is practically inaccessible.
As usual the service people are fully booked.
Any suggestions?

[TaxWonk]

How old are your house batteries? Since the lights are dimming, are your batteries fully charged? it could be a battery connection, so that would be the first thing I would checked. Next I would monitor the voltage at the batteries and make sure the voltage is not dropping too much. Generator starters like 12 volts if you are seeing below 10 volts at your batteries then it could be your batteries.

The service manual has a very detailed trouble shooting guide.

https://onan.xmsi.net/981-0506%20Ona...0(03-1991).pdf

Good luck.

[mkguitar]

check first the battery and cables to ensure that the starter is getting power


a good battery will be able to provide the high current power the starter needs, your running engine or shore power cannot





a "clunk" may indicate that power is sufficient and that the solenoid switch is moving


in this case, holding the starter button down can further damage the solenoid ( contact points, disk) or the starter windings can burn if the starter is not turning ( expensive) a whine can indicate the windings burning




often with a duff battery the solenoid will "chatter", it will have enough power to the coil to move the contact disk, but when it makes contact the power to the coil collapses and the disk will retract, then be pushed forward again and the cycle repeats
-the contacts and the disk can arc causing pitting on the disk and leaving carbon deposits

(most solenoids can be serviced by flipping over the contact disk to the clean side )




if the battery and cables are good



the starter and solenoid will have to come out for service


most solenoids and starters are easily serviced they are simple devices


in a starter if the windings are burnt, it is done.


otherwise the bearings may be worn, worn brushes or the commutator ( the spinny part ) cleaned, sometimes with a hacksaw or thin blade to remove insulating material build up


the service manuals are available on the web to download







mike

[ChicagoTom]

Never start the generator while on shore power.

[ChicagoTom]

Having the chassis running will give it a boost. I’m not sure why you think that. It gives a boost to the house battery and that in turn gives a boost to the generator. Have you ever stated the chassis with the fantastic fan on. Just listen to it increase speed. Same concept.

[RT-NY]

Something similar happened to me once and (I think) the problem was that the starter gear was hung up the flywheel. I managed to get a socket in there to manually turn the flywheel and that freed it up and it was able to start.

[RT-NY]

. . . also, you should probably not ever try to start an Onan 2800 on an older RV without the engine running. I think what caused the gear to hang up was trying to start it with a insufficiently charged battery.

[Brital]

The problem was the solenoid and the starter gear. The return spring was very weak and the gear was worn and jammed. The solution was a new starter.