Onan 2800 Shuts Down After Start

[Deiganator]

Hi all,

Looking for some advice! My Onan Microlite 2800 (gas) starts then shuts down between 5-10 seconds.

History:
- Purchased 1999 Islander with built in generator in September 2017
- Generator ran OK, but needed a tune up (hard to start after off for awhile, blows a bit of white smoke at start up, occasional surging)
- Changed oil (spilled a bit in the bottom of the case)
- This problem started immediately after changing the oil
- Changed the spark plug (old plug was covered in oil), issue still persisted
- Changed the air filter, no change
- Changed the fuel filter, set would not start at all
- Drained a bit of oil (from 7/8 to "1/8") as I read that the sensors on these sets can falsely read overfull, no change
- Next day tried again, started and shutoff again, would not start again
- Sprayed some carb cleaner in, started and shutoff again
- Now back to same issue, start and shuts off after 5-10 seconds

I am thinking its the oil pressure switch, but not sure if there is anything else I can try before the major project of pulling it out of the RV to service the sensor?

Thanks!

[hbn7hj]

There is no oil pressure switch. There is an oil level switch. I've never heard of an over full sensor. Just guessing but if it isn't too low oil it may be a failing fuel pump. Once the carb bowl empties, the engine quits.

[Deiganator]

Ha! Of course as soon as I post I sort it out. It was the oil sensor (whatever it senses). I disconnected it and it runs fine (aside from white smoke).

[lgpacker]

Could you answer exactly how you disconnected the low oil switch? From my reading and engine examination, the wiring isn't readily accessible and neither is the switch itself in the oil pan. Oh, your exact engine model number would be helpful too. Thanks.

[Deiganator]

It was on the right lower side near the control module, a single wire with a pig tail connector, hard to reach and will probably never be able to reconnect it without totally removing the set. Model is FA26100G.

Oh and after a second oil change (oil was still dirty after first) and a good run for a couple hours, there's no more smoke

[rowiebowie]

Originally Posted by Deiganator

It was on the right lower side near the control module, a single wire with a pig tail connector, hard to reach and will probably never be able to reconnect it without totally removing the set. Model is FA26100G.

Oh and after a second oil change (oil was still dirty after first) and a good run for a couple hours, there's no more smoke

Good to hear. Thanks for the update.
.

[Joe]

Have had many problems with my Onan 2800. I have replaced or had replaced the carberator, oil level switch, starter, muffler, pipe and stater. Now I have a intermittent tapping sound. It does not always keep up with rpms. Sometimes it tapps seconds apart then stops for a few. Also, the other day I left a freezing climate. I spent the night in a much warmer area. I had left the generator in winter mode. The temp got up to high 70s. The generator stopped and would not start. About an hour later I started it and seemed to run fine. Any thoughts???