7500 Onan Quiet Diesel Temp sensor, thermostat, glow plug, replace/repair
This is my 2004 38N Fleetwood Bounder with quiet diesel Onan generator. Generator would die after running approx 2-3 minutes but would start right back up and die again, over and over. Code from generator was "33". High temp code, however the coolant was cool as a cucumber when I checked it after several restarts and shutdowns. So after some research I determined it was the coolant sensor was bad. My generator unfortunately does not slide out on a tray so I had to get a little creative and remove from the bottom because the entire top panel has to come off the unit. Now I am not a mechanic, RV tech, or otherwise, but I am a little knowledgeable of how things work and how to do some minor repairs. So I was able to use my motorcycle jack, some 6"x6" blocks, the RV's front hydraulic leveling jacks, and a few wrenches, removed the generator from the RV and repair it out in the open. I done it completely by myself and although it was a little time consuming (about 5 hours start to finish) I was able to successfully make the repairs and reinstall it back in the RV and fire it right up. But I'll tell you, if you have a buddy to help hand you tools and such it would of made it a lot easier and you wont be as sore as I was from getting up and down, crawling under and out from underneath getting my own tools. Also I replaced the 3 glow plugs due to the unit being extremely hard to start at first start up, would crank, crank, crank, cough, smoke, crank some more and finally start. Ordered all the thermostat parts from ebay, all OEM Onan parts for about $80, ordered the glow plugs from ebay as well, all OEM Onan plugs as well for what I thought was a WHOPPING price of about $150. But before I decided to do this myself I checked with a RV dealership and was given a ballpark price of $1000 just for labor. So it didn't take me too long to decide to do some research and tear into it myself. Hope this helps someone out, I couldn't find any videos on this particular repair.
Пікірлер: 28
I put 10,000+ hours on this model genset and it was an incredible quiet and fuel efficient generator, zero issues
@alejandrocortez2116
3 ай бұрын
My 7500 Cummins diesel generator is at 9578 hrs … was kinda scared when I purchased the rv ,,, but it runs great …
It helped me a whole lot. I sure do appreciate it Lauren, where the sensors are at glow plugs. Thank you again.
Great job explaining process, bolt head sizes and type jack used. I have an 02’ Tiffin Phaeton and getting ready to pull mine out. Thanks for the help.
I just changed mine is in drawer and comes out almost halfway so I was able to fix it in place by removing the top, right side, and back of cabinet. I had to crawl under and behind the generator to reach the temp probe. I did have to use a horseshoe shaped wrench to get the probe out. I did check the coolant level and temp, as well as removed the thermostat. It just was not running hot. if parts are on hand it can be done in one day. I changed the probe and thermostat both were in stock at the closest cummins dealer. If you try to test it before you reinstall the cabinet it will run a while longer but will overheat due to lack of air flow. Thank you Jeff for the video it was the only thing I found that put me on the right track. I don't even want to know how much it would cost in time or money to have this done in a shop.
@jeffbond001
4 жыл бұрын
Hey glad it was of some help! I was given an estimate at a RV Dealership of $1000.00 labor plus parts. Best I remember all the parts with the 3 glow plugs (glow plugs definitely the most expensive parts) was about $400
@hondaautorepair128
3 жыл бұрын
Paul, I have a 2005 Phaeton with Onan on pull-out like yours. Ordered the temp sensor and thermostat and attempted to replace today. For the life of me, I could not get the old temp sensor to break free. It is a very tight space but I could get a19mm socket on the sensor but not enough room for the socket. My socket was a 6 point but even so it tended to round the corners off the old sensor. You post mentioned using a horseshoe shape wrench. Where did you find such a creature or did you just make one out of and old 19 mm wrench? Help!
@paulferguson6624
3 жыл бұрын
@@hondaautorepair128 Sorry I don't have you tube notifications turned on I just happened to look at the video again. The wrench I used was one of a set that my mother bought me years ago I had never found a use for them until now. I have no idea where she found the thing she found below is a link to a picture. I hope you got it out by now but at least you will know what i used. By the way my motor home is an 03 Phaeton. drive.google.com/file/d/1VFgDsRfJ7vS9dB8uXXkRnzuBaM81tzx_/view?usp=sharing
Thanks, I have a Discovery on a Freightliner. My generator runs between 55 and 65 seconds and stops but well start immediately. Today I order the sender unit part # 193-0318. I have the some jack. Here I go.
Great video,Nice job.
Awesome video!! I have the same issue with my generator and have been dreading removing it.
@jeffbond001
4 жыл бұрын
It really wasn't all that bad, if you have a helper to hand you tools and such it would be even easier and quicker. Thanks! Jeff
I have same generator in my semi truck for my big sleeper... I was prepared to drop generator but look like i can pull my big stainless box and get those 10mm bolts to replace the sender...
Thank you so much. I am looking at removing mine and it's in the same way.
@jeffbond001
4 жыл бұрын
It's really not hard to do, just time consuming. If you have a helper to hand you tools it'll save a lot of time. I feel like it went back in easier than it came out, probably because I already knew what I'd need and how it was done.
Thank you jeff for your video, I have a question for you if you have some time for me. I have the same generator and It runs great but no power is coming out of the unit after power stopped while using convection microwave. Where do I test with my meter to see if generator is making power? All breakers are good and I have a error code of #38. Thank you Dave
I am having the same problem but am having absolutely no luck locating the sending unit. (1930318) any suggestions on where to look?
Please share the parts list. My gen just started throwing the temp code at me so now I get to follow in your footsteps...
@jeffbond001
3 жыл бұрын
7500 Quiet diesel Onan, HDKAJ. Here's the parts list I needed. Onan water temp sender 193-0318, Thermostat A046Z961 185-5458, Thermostat housing gasket 185-2238, Bypass hose 185-5722, Glow plug 185-5421, Water pump belt (which I didn't change but if yours looks at all worn this would be the time to do it since it's exposed) 511-0235. Also the inline fuel filter is Wix brand 33252. I ordered everything online and a few parts from eBay, saved me quite a bit of bucks rather than going to Cummins dealer. Its really not that hard to do, especially if you have a helper. Mine's still running strong. Hope this helps. Jeff
Thanks, I have same issue mine runs 5 minutes then coolant code. How did you know it was the sensor? Would hate to do all this and not fix problem
@paulferguson6624
4 жыл бұрын
If the temp probe is your problem it just won't be hot. see my comment above.
@jeffbond001
4 жыл бұрын
I just went by research and the code flashes on the unit itself. It was giving a high temp code but the coolant was never even warm. So after research I was 99% sure it was the problem. My temp sensor had a lot of buildup attached to it, made me wonder if periodically changing the fluid would of helped? Also I have all the part numbers if that would help you. They were a little hard to find, but I'll be glad to post them if you need them. Jeff
@iscreamcandytv9642
3 жыл бұрын
@@jeffbond001 pls share part info
can. you run the generator out of the rv to be sure it is right? i have this to do and want to make sure it runs right before I put it back in.
@jeffbond001
Жыл бұрын
Sorry for such a delay in my response. I don't think you would be able to run in out of the vehicle because your fuel lines won't reach that far to hook back up.
@FreedomIsntFree2023
Жыл бұрын
Just for future reference......Yes, you can operate the genny outside of the RV to test before reinstallation. This will require some creativity on your part. So, to do this, you'll need to run a supply and return fuel line to some type of jug (gas can, milk jug, coffee can, etc.) with an appropriate amount of fuel in it. Then you can fashion a battery source to connect to the +/- terminals on the generator. Battery jumper cables will work fine for this. Lastly, if you plan to run the generator for more than a few minutes, make sure all the sheet metal covers are back in place, as the cooling system relies on those to direct air flow across the radiator.
Was it shutting down because of the temperature probe?
@jeffbond001
Жыл бұрын
Yes, the temperature sensor was bad, telling the computer it was too hot, therefore shutting the generator off.