Onan no start

[g1g]

I have a 1994 Onan 2.8 KW model KY. It was running great just a couple days ago but now as soon as I let go of the start switch it dies. Runs nice as long as the switch is pressed. The oil is full and recently changed with synthetic and the tank is full of gas. I get he same thing if I try the switch by the genny as when I use the remote start.

[TEXAS]

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

[gunny357]

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.

[Handbasket]

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."

[g1g]

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

[JaxDad]

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.

[TEXAS]

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.

[powderman426]

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.

[j-d]

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.