Onan shuts down

Multiengine · 07-06-2010, 08:05 PM

Onan 7500 watt Diesel shuts down under load after about 5 min. Codes say high coolant temp shut down ?????. Coolant and oil OK, air inlet and outlet OK. Gen. has 140 hr. Drained coolant, flushed and refilled no help. Can't get into shop before the 15th any ideas?

thanks
Dave

KennethM · 07-07-2010, 03:32 AM

Dave, just a thought but the Onan has a water pump belt that may have seen its useful life and be loose or broken. The problem with our coaches that an easy repair is made almost impossible because you have to lower the Onan out the bottom of a raised coach to remove the top cover. The Onan weighs just about 500 lbs so it is not something most owners would attempt.

squeak · 07-07-2010, 07:49 AM

Dave before you do anything check underneath the gen. you will see the radator and make sure that it is clear. mind had leaves paper grass hosed it off now it is fine. I have changed my belt on my onan when it was in my MH lot of work.

AFChap · 07-07-2010, 11:48 AM

I had shut down due to "coolant temp" code after I had the coolant changed. After one shutdown I heard the coolant gurgling. I had to pull the coolant fill tube out of the enclosure and run it awhile w/o the cap to "burp" all the air out. If there is an air pocket, the genny will shut down with a hi temp error even though the coolant itself is not hot.

squeak · 07-07-2010, 10:06 PM

ok all is fine?

RVDude · 07-07-2010, 10:28 PM

AFCHap has it, burp that radiator cap!

After changing the coolant it takes a while to get it to completely fill all the internal areas. Running it open and then capping it for a while and then just cracking the cap when slightly warm will all help get the air out.