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5-8 Error Code on Onan 7KW Gas Generator

MobileAviator
Explorer
Explorer
My Class A Gasser has an Onan 7KW gasoline powered generator. The rig was purchased new in August 2015, the generator has had regular annual maintenance with semi-regular monthly exercise, and currently has 346.5 hours and is due it's next service.

A couple of months ago, the generator died after running @ 1/2 hour, and the status light on the generator itself showed error code 5-8 indicating excessive exhaust gas temperature. The error code on the dash mounted hour meter shows 8111.5.

Recently, the run time got as low as 5 minutes until shut down, and now will not start at all, immediately showing the 8111.5 error code on the hour meter.

Thinking there might be a wasp nest or other exhaust pipe blockage, I ran a flexible drain cleaning tool up the exhaust pipe, but there was no evidence of blockage.

I've downloaded the Onan Mobile Gen Set Service Manual, Part 1 and Part 2, but the trouble shooting section stops at error code 5-7. Go figure!!

Any ideas or suggestions?

Thanks!!!
3 REPLIES 3

GREGORYJ
Explorer
Explorer
I assume the error code was read counting the 2 sets of the number of
blinks by the start button red light, that is after the first 3 blinks showing a shut down, then pressing the start button once showed 5 blinks followed by 8 blinks for code 58.
Ellen & Greg
08 National Dolphin DL-35Ci, Kelderman Air Ride, Rear Trac Bar
Workhorse W22, RoadMaster Rear Sway Bar, Towing 08 Smart Car

Horsedoc
Explorer II
Explorer II
Where does one see these codes?
horsedoc
2008 Damon Essence
2013 Jeep Sahara Unlimited
Blue Ox tow

K_Charles
Explorer
Explorer
Code 81: Exhaust Gas Temperature Sensor Open
Code 58: Exhaust Gas Temperature Shutdown