Onan 8000 quiet diesel shutting down code 33 fix
After many hours of frustration before coming up with the fix, i'm thinking I can save someone aggravation and money by sharing my experience. My genset has 405 hrs. mounted in a 2003 Travel Supreme. Everything was going along fine until one day the genset started shutting down after only a few minutes of running under load. The fault code 33 indicated an overheating shutdown. The fix turned out to be a combination of temperature switch and a cooling system in need of a good flushing. When I removed the temperature switch it was sludged in so bad the lower half broke off and stayed in the housing. When I tried to remove the broken piece with an easy out it dropped into the water jacket instead; hope it doesn't cause problems later. I finally got a new sending unit installed. Then I gave the unit a good flushing with Fleeetguard Restore according to directions on the container, I also changed the thermostat and gave the unit an oil change for good measure. Touch wood everything is running as it should. I'm thinking a lot of problems could be avoided by flushing the cooling system as a matter of general maintenance. A good quality 50/50 diesel anti-freeze, anti-corrosion should be used to re-fill. Drive safe.