Onan no start

Please post the complete Model and Serial Numbers. The Spec Code (last character in Model Number) is particularly important. With that info, somebody here should be able to send you a Service Manual.

Some if the older Onan's had a wire wound resister that would drop the voltage and save wear and tear on the ignition system. When cranking it bypassed the register giving full voltage for starting. If the resister opens you will get that symptom. It's easy to check by putting an ohm meter on it.

Most common problem is no AC output. With the full model and serial number. You can get the service manual. Has all the test you need to check it out yourself.

Check your coach battery charge state and the connections of it.

If the battery is just a little low (but still lots to start the genset) it will not allow it to run since they work on a power in / power out basis. Anything below 12 volts will give you less than 120 volts.

I did find out it is a KV not the ky i stated earlier. model 2.8 KVfa26100c so I take it that it is a spec C and serial# f943187708

The battery has _nothing_ to do with it as long as it will start it. You're seeing either a failure in a safety like the low oil switch or a failure to produce voltage.

These 2800 Onans (I've owned 3) get the starting ignition current from the battery while cranking, but change over to self-generated power when the start switch is released.

Both of my similar failures have been failure to produce voltage; once under warranty, it was the rotor/stator, the other time it was the voltage regulator. Fairly easy to diagnose with the service manual and a volt-ohm meter. There's also troubleshooting steps at the Flight Systems website.

All 3 of mine were built after they deleted the low oil switch. Not sure about yours. If you have it, it's a possible source. Also be sure you're checking the oil level the right way. For all of mine, after wiping the dipstick, it's to be rested in the lip of the hole, _not_ screwed in. If you read it after screwing it in, you are always low on oil.

Good luck with it. They can be dang frustrating.

Jim, "Instant human, just add coffee."

Handbasket wrote:
The battery has _nothing_ to do with it as long as it will start it. You're seeing either a failure in a safety like the low oil switch or a failure to produce voltage.

These 2800 Onans (I've owned 3) get the starting ignition current from the battery while cranking, but change over to self-generated power when the start switch is released.

Both of my similar failures have been failure to produce voltage; once under warranty, it was the rotor/stator, the other time it was the voltage regulator. Fairly easy to diagnose with the service manual and a volt-ohm meter. There's also troubleshooting steps at the Flight Systems website.

All 3 of mine were built after they deleted the low oil switch. Not sure about yours. If you have it, it's a possible source. Also be sure you're checking the oil level the right way. For all of mine, after wiping the dipstick, it's to be rested in the lip of the hole, _not_ screwed in. If you read it after screwing it in, you are always low on oil.

Good luck with it. They can be dang frustrating.

Jim, "Instant human, just add coffee."

Great advice here.

Good advice from Handbasket. Onan stopped using the low oil level switch. Because it caused so many false shutdowns. Just unplug the switch wire.