Community Forums

Gadget Man · 11-20-2012, 02:27 PM

My motorhone is equipped with an Onan 7.5kw diesel generator.

I took my coach to my local RV Onan authorized repair facility to have them service my genny’s cooling system. They did not want to change out the t-stat because my genny in not on a slide. They said the entire generator would have to be dropped from the MH chassis in order to get to the genny’s t-stat, which would cost me big $$ for labor. The service manager said they would be happy to change the coolant (I can do that myself), but recommended running the genny with the factory t-stat. He added that the genny would shut itself down if it were to overheat due to a faulty t-stat, but claims they have never had a customer come in with one that was bad.

Again, this is a factory authorized Onan RV Generator repair shop. Anyone else run into this?

Craig

tquarles · 11-20-2012, 03:04 PM

Not exactly this, but when I had the temp. sensor fail on the *last* day of my warranty, I'm really glad I stopped at the nearest cummins dealer and logged it, even if they couldn't even look at it that day. When I eventually got it in to my regular dealer for the work, it required 6 hours of labor to remove my non-slide generator from the rig, 30 minutes to open it up, replace the temp. sensor, test, load test, close it up, then 4 hours of labor to put it back in.

at $110/hour.

Sure glad that was on cummins/onan's tab.

Everything else in my generator except filters/fluids is factory original and I'm not looking forward to the day I have to have it removed on my dime for service.

Gary RVRoamer · 11-20-2012, 08:19 PM

Having changed one this past summer, I can attest that the thermostat is hard to reach if not on a slide. I help a buddy on his 2004 HR Endeavor - we had to get at the coolant temperature sensor which is on the housing below the t-stat and it was a real bear.

The top cover of the Onan 7.5 has to be removed and the t-stat is all the way in the back. If you can get the cover off without pulling the genny out, then maybe, just maybe, you could reach in far enough to get at the thermostat housing.

I would not change the thermostat unless there is a problem with it. The coolant temp is monitored closely by the genny's controller, and if the temp sensor fails, there is a check on that as well. Don't worry about it.

Gadget Man · 11-21-2012, 09:19 AM

Thanks Gary. You're one of the most knowledgeable people in here. In fact, I trust your word more than that shop manager. I feel more at ease now...

Craig

Gary RVRoamer · 11-23-2012, 09:39 AM

I'm blushing!

Barlow46 · 11-25-2012, 06:15 PM

Craig..hit the "thanks" button for Gary....he needs more "campfires" for all that he does for us.

Genset · 11-27-2012, 07:30 AM

We have found on the older Onan 7.5DKD model, the most frequent failure was the V-Belt on fan/water pump failing, about every 3-4 k hours. This is prior to the sound housing models. I am certain there are many tuff areas to get into the newer models, just changing oil etc can be difficult on some installations.
Cheers
Dave