spray some penetrating oil like PB blaster, kroil or liquid wrench on it and place your socket on it and tap lightly with a hammer do this several times to allow oil to penetrate.
don't use an impact hammer.
kg5388 wrote: spray some penetrating oil like PB blaster, kroil or liquid wrench on it and place your socket on it and tap lightly with a hammer do this several times to allow oil to penetrate.
don't use an impact hammer.
Last night I had already started the Liquid Wrench penetrating oil procedure, and I continued this morning. I followed your instructions on the tapping, penetrating oil, and trying to loosen the sender. It finally started turning, and I was able to unscrew it off. Except, the internal 'bulb' was corroded stuck, and broke off. I had to stuff an oiled rag into the thermostat housing(to catch the chips), and then drilled it out with my long 3/8" drill bit. Then, had to size the hole to original .396" diameter.
I put it all back together, with new sensor and thermostat, carefully filled it with coolant, and cranked it up.
It ran for 25 minutes and quit. I waited 5 minutes and restarted it. It ran for 10 minutes and quit. The fault code is still 33.
In other words, there was no change in the symptoms.
So, the thing that comes to mind is that if it's still overheating and commanding a shutdown, perhaps it's a pump impeller that's faulty, somehow. Heck, I don't even know how to check to see if water is circulating.
But, I'm glad I went through this process of elimination. With 1,058 hours, it was time to do it anyway.
And, I truly appreciate it. You've helped me a lot. It's just one of those things, where I have to continue with the education.
Willie & Betty Sue
Miko & Sparky
2003 41 ft Dutch Star Diesel Pusher/Spartan
Floorplan 4010
Blazer toad & Ranger bassboat
kg5388 wrote: did you have the top off when you ran it? that will cause it to overheat.
you need to check the temp when it shuts down
I had it completely buttoned up. I even plugged the hole I made in that plastic partition. The radiator is clean, the pump pulleys and belt are intact, everything visible is as it was when everything was working normally.
Check the temp? Oh how I wish it had an ole analog temp gauge that I could do that with. All I have is a infra-red thermometer gun with laser sight. So, how/where do you check the temp?
Thanks
What I'm saying is that I not only don't know the standard procedure of monitoring the exact temperature of the coolant, I don't even know at what temperature the Onan system commands it to shut down.
I find nothing in the owner's/operator's manual to help me with this.
Also, it might seem that I'm 'stubbornly' directing my attention to a possible malfunction of the cooling system. However, there ARE two main developments which drive me to still suspect something in the cooling system. Firstly, there is the fault code (33). Secondly, the duration of the two 'runs' is consistent with what I would suspect would occur if the engine was overheating (25 minutes followed by 10 minutes).
Question: Do Onan specialists use a temperature gauge that hooks up to the 'electronic box', in order to monitor the exact temperature?
I ask because I noticed in the manual that some vehicles(RV's) come equipped with a remote control panel which has water temp and oil pressure gauges.
Thanks
kg5388 wrote: i just lift the top and hit the thermostat housing with a temp gun.
96bounder30e has the parts and service manual for your genset send him a pm at the top right of the page and he will email it to you for free
I requested a copy of the Repair/Service Manual, but apparently Bounder is not yet in service...
Meanwhile, I ran the temp test.
The starting temp, at the thermostat housing, was 92* and the ending temp, one minute after it quit, was 240*
True to form, it quit after 26 minutes of running.
I'm scratching my head, thinking. On the surface, the 240 sounds like a reasonable cutoff temp,....but I don't have any reference, other than the normal running temp of the 8.3 Cummins ISC, which is 200 to 210.
If I assume that this Onan quits due to a command due to overtemp, then it kinda puts me back where I started. Or, I can look for something OTHER than those items I've replaced:
Low water level? The only thing there that I can imagine is the kink in the long filler hose. I suppose I could shorten it and that would keep it from kinking.
Water not circulating? The only thing I can think of is removing the water pump and checking it.
I'm still working on solving the overheating problem with my 7.5 Onan QD, and I'll have an update soon. But, I wanted to post this photo for Kevin, as he's been helping me via PM.
The photo shows some buildup 'stuff' that came out during one of the times that I drained the system.
I have NOT found the fix to my Onan overheating problem. Apparently, this problem is rare enough that I haven't found anyone who has run into something similar.
I haven't even been able to verify that the controller is programmed to shut down whenever the temperature reaches 240 degrees. Onan's customer service does not give out technical information unless you're a registered Onan dealer/repair station.
The ONLY commanded shut-down fault code that it has ever produced is #33. Plus, every time that I've taken a temperature reading, it's been 240* at the thermostat housing (right after it quits). This is the reason I'm still looking at the cooling system. The next thing that I was going to do is replace the water pump, ALL hoses, plus remove the radiator and have it taken apart and cleaned (radiator shop).
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