philcarrell Posted August 17, 2023 Share Posted August 17, 2023 I have a 10KW HDKA generator that will not stay running. It started last year and would run about 3 hours shut down and there was a 3-6 code, air filter or fuel filter. I replaced both and next rip same thing, same code. After it shuts down you can wait a bit clear the code, start it back up and it will run about an hour. It sat all winter not being run and we just got back from our last trip same thing same code. I looked up in the air intake and did not see any obstructions. I don't think it is either filter as I don't have any engine or Aqua Hot fuel issues. Any thing else I should check. Link to comment Share on other sites More sharing options...
CMillet86 Posted August 17, 2023 Share Posted August 17, 2023 On my 7500, there was a wire that had come loose Inside the case, it was just a spade terminal, it either wouldn’t start or wouldn’t stay running. I’m not sure if the 10k is the same. But I would also look at your fuel pump. Link to comment Share on other sites More sharing options...
D.Ellison Posted August 17, 2023 Share Posted August 17, 2023 My 10kw did the exact same thing your describing and a short version of a long story is i had to replace the control unit , basically the fuel pump stops running others had run an extra toggle switch but i was wanting my ags system to work so replaced the controller with one from flight systems and it took care of it . If it comes to that the part # is on the old ecm. 1 Link to comment Share on other sites More sharing options...
Dr4Film Posted August 17, 2023 Share Posted August 17, 2023 Bad sensor possibly giving you a false code. Link to comment Share on other sites More sharing options...
Tom Cherry Posted August 17, 2023 Share Posted August 17, 2023 2 hours ago, CMillet86 said: On my 7500, there was a wire that had come loose Inside the case, it was just a spade terminal, it either wouldn’t start or wouldn’t stay running. I’m not sure if the 10k is the same. But I would also look at your fuel pump. Yes and NO. The boards are quite different. The 10 (maybe the 12) are prone to water (or coolant) damage and NOT as robust as the 7.5 or 8 KW. Most mobile techs, if they’re worth a cuss, will carry a NEW board. Some only a rebuilt one…or some, BOTH… sad but true… Link to comment Share on other sites More sharing options...
Flyinhy Posted August 17, 2023 Share Posted August 17, 2023 I had the same problem when I purchased mine. Ended up being the main control board. Flight Systems at the time was working on a prototype board and sent it to me for 300 dollars. Still working just fine. Ivan is the man who needs to chime in on this thread. Link to comment Share on other sites More sharing options...
96 EVO Posted August 17, 2023 Share Posted August 17, 2023 7 minutes ago, Tom Cherry said: Yes and NO. The boards are quite different. The 10 (maybe the 12) are prone to water (or coolant) damage and NOT as robust as the 7.5 or 8 KW. Most movile techs, if they’re worth a cuss, will carry a NEW board. Some only a rebuilt one…or some, BOTH… sad but true… Likely leaking onto the controller from their Crappola, leaky overflow tanks! I patched mine up a couple of times. It's now living it's golden years in the landfill! I replaced it with a generic aluminum bottle, mounted outside the cover. Link to comment Share on other sites More sharing options...
philcarrell Posted August 17, 2023 Author Share Posted August 17, 2023 15 minutes ago, 96 EVO said: Likely leaking onto the controller from their Crappola, leaky overflow tanks! I patched mine up a couple of times. It's now living it's golden years in the landfill! I replaced it with a generic aluminum bottle, mounted outside the cover. No leaks on rank Link to comment Share on other sites More sharing options...
Ivan K Posted August 17, 2023 Share Posted August 17, 2023 I have a 12.5 with Isuzu motor but the principal remains the same. As far as code 36, it is a catch all code for uncommanded shutdown (ie. the controller has no clue) and yes, is usually associated with fuel supply but not always. I got that same code 36 with burned out stator. But relax, that's not you case. Since your genny runs for hours before shutdown, it'll be difficult to wait and check for a specific reason this long. Any of the above responses are a possibility. But my question is, what is happening after the shutdown while you can't restart and have to wait an hour or so? Do you hear the pump clicking while priming or just before it turns over? Does it even turn over, likely yes, right? The pump is powered from the controller so it depends on your answer. Link to comment Share on other sites More sharing options...
philcarrell Posted August 17, 2023 Author Share Posted August 17, 2023 2 hours ago, D.Ellison said: 2 hours ago, D.Ellison said: My 10kw did the exact same thing your describing and a short version of a long story is i had to replace the control unit , basically the fuel pump stops running others had run an extra toggle switch but i was wanting my ags system to work so replaced the controller with one from flight systems and it took care of it . If it comes to that the part # is on the old ecm. Sounds like my problem Link to comment Share on other sites More sharing options...
David Pratt Posted August 17, 2023 Share Posted August 17, 2023 This is a known problem with the Onan QD 10K and 12.5K Generators. Code 36 is a generic code and it means the Generator shut down from and outside source or the operator. Cummins will tell you it is fuel related because it has no stored codes or you may have low fuel or a weak fuel pump that is intermittently shutting the Generator down. IT IS NONE OF THESE. The issue is the Control Unit that is at fault and needs to be replaced. Do NOT REPLACE IT WITH A NEW ONAN CONTROL BOARD OR YOU WILL STILL HAVE THE PROBLEM. If the generators starts and runs normal and then for no reason it shuts down, but it will re-start and run normally again this is the issue. The generator may run only a few minutes or a couple of hours and shut down for no apparent reason, but will always restart and run again. Sometimes the Generator may run normally for several hours or cycles without the issue. Mike Hadley, who purchased my 05 Exec started to have the issue with the 10KQD. Sometimes the generator would start and run for several hours and several cycles/days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart and run for hours and cycles and days before it would do it again. On a couple of occasions it would not restart until it had set for a while. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit, but did admit it was an issue they new about and had no fix. I was having this same issue with the 12.5QD in the Foretravel since new. Sometimes the generator would start and run for several hours and several days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart, run for hours/cycles and days before it would shut down again. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit. Cummins finally did replace the control unit and it ran normally for a few trips and started again, but not as bad, but still with the symptoms. Thankfully all the repairs were covered under warranty. Mike found a company, "Flight Systems, Inc " that sells rebuilt Onan Control Units for half the price of the new Onan Control unit. He purchased a rebuilt Control Unit from the and replaced the Onan Control Unit and it solved the problem. No more Shutting down. I had a Mobile Technician come out and Verify that I was having and issue with the generator shutting down and the Extended Warranty approved the replacement of the Control Unit. I replaced it with a rebuilt Control Unit from Flight Systems, Inc. My generator has not shut down since the Replacement. Several other members who were having the same issue with their 10K/12.5K generators have purchased the Flight Systems rebuilt unit and the problem was fixed. This may not fix the issue with your 10K/12.5K generator, but it might be worth looking into. The Onan part number for the Control unit is 300-5961. The Flight Systems replacement part number is 56-5961-00 for their rebuilt unit. Cummins/Onan cost for their new Control Unit is $1000-$1200. Flight Systems price for their rebuilt unit is $695.00. The rebuilt Control Unit is sealed an epoxy material to prevent moisture contamination. Flight systems contact info is; https://www.flightsystems.com 1-800-333-9912 2 Link to comment Share on other sites More sharing options...
Tom Cherry Posted August 17, 2023 Share Posted August 17, 2023 44 minutes ago, David Pratt said: This is a known problem with the Onan QD 10K and 12.5K Generators. Code 36 is a generic code and it means the Generator shut down from and outside source or the operator. Cummins will tell you it is fuel related because it has no stored codes or you may have low fuel or a weak fuel pump that is intermittently shutting the Generator down. IT IS NONE OF THESE. The issue is the Control Unit that is at fault and needs to be replaced. Do NOT REPLACE IT WITH A NEW ONAN CONTROL BOARD OR YOU WILL STILL HAVE THE PROBLEM. If the generators starts and runs normal and then for no reason it shuts down, but it will re-start and run normally again this is the issue. The generator may run only a few minutes or a couple of hours and shut down for no apparent reason, but will always restart and run again. Sometimes the Generator may run normally for several hours or cycles without the issue. Mike Hadley, who purchased my 05 Exec started to have the issue with the 10KQD. Sometimes the generator would start and run for several hours and several cycles/days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart and run for hours and cycles and days before it would do it again. On a couple of occasions it would not restart until it had set for a while. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit, but did admit it was an issue they new about and had no fix. I was having this same issue with the 12.5QD in the Foretravel since new. Sometimes the generator would start and run for several hours and several days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart, run for hours/cycles and days before it would shut down again. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit. Cummins finally did replace the control unit and it ran normally for a few trips and started again, but not as bad, but still with the symptoms. Thankfully all the repairs were covered under warranty. Mike found a company, "Flight Systems, Inc " that sells rebuilt Onan Control Units for half the price of the new Onan Control unit. He purchased a rebuilt Control Unit from the and replaced the Onan Control Unit and it solved the problem. No more Shutting down. I had a Mobile Technician come out and Verify that I was having and issue with the generator shutting down and the Extended Warranty approved the replacement of the Control Unit. I replaced it with a rebuilt Control Unit from Flight Systems, Inc. My generator has not shut down since the Replacement. Several other members who were having the same issue with their 10K/12.5K generators have purchased the Flight Systems rebuilt unit and the problem was fixed. This may not fix the issue with your 10K/12.5K generator, but it might be worth looking into. The Onan part number for the Control unit is 300-5961. The Flight Systems replacement part number is 56-5961-00 for their rebuilt unit. Cummins/Onan cost for their new Control Unit is $1000-$1200. Flight Systems price for their rebuilt unit is $695.00. The rebuilt Control Unit is sealed an epoxy material to prevent moisture contamination. Flight systems contact info is; https://www.flightsystems.com 1-800-333-9912 AMEN. You expanded what I know and several members have experienced. A friend sold his 3 year old, meticulously maintained 09 Camelot. Called me and said new owner has a Genny issue. He was providing support as David does. We three way talked to tech. He “made us smart”, but I was multitasking. Bingo. Real issue. He carried both new (Onan) and Flight (rebuilt). The new owner opted for Flight. Last I heard a few years ago…Genny working like a Timex watch. I talked once to a Flight tech support guy. Very smart and their website did or has a lot of great tech and troubleshooting help. I admit to forgetting the name “Flight” or I would have included. David has more insight and research and such and has facts, not shooting from hip. Thanks for filling in a lot and also confirming my recollection of this issue AGAIN….THE 7.5/8.0 are not as prone or hardly ever…so be aware if is the 240 models (10 & 12.5]. Link to comment Share on other sites More sharing options...
Georgia Mike Posted August 17, 2023 Share Posted August 17, 2023 When I bought my Dynasty with a 10k Onan the guy had just replaced the control board and said it was $1000. So does it get wet or is there something you can do to prevent it from failing? Is the one from Flight systems sealed better? Link to comment Share on other sites More sharing options...
96 EVO Posted August 17, 2023 Share Posted August 17, 2023 2 hours ago, philcarrell said: No leaks on rank Lucky you! Maybe The HULK was on vacation the day your tank was assembled. Link to comment Share on other sites More sharing options...
philcarrell Posted August 17, 2023 Author Share Posted August 17, 2023 1 hour ago, David Pratt said: This is a known problem with the Onan QD 10K and 12.5K Generators. Code 36 is a generic code and it means the Generator shut down from and outside source or the operator. Cummins will tell you it is fuel related because it has no stored codes or you may have low fuel or a weak fuel pump that is intermittently shutting the Generator down. IT IS NONE OF THESE. The issue is the Control Unit that is at fault and needs to be replaced. Do NOT REPLACE IT WITH A NEW ONAN CONTROL BOARD OR YOU WILL STILL HAVE THE PROBLEM. If the generators starts and runs normal and then for no reason it shuts down, but it will re-start and run normally again this is the issue. The generator may run only a few minutes or a couple of hours and shut down for no apparent reason, but will always restart and run again. Sometimes the Generator may run normally for several hours or cycles without the issue. Mike Hadley, who purchased my 05 Exec started to have the issue with the 10KQD. Sometimes the generator would start and run for several hours and several cycles/days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart and run for hours and cycles and days before it would do it again. On a couple of occasions it would not restart until it had set for a while. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit, but did admit it was an issue they new about and had no fix. I was having this same issue with the 12.5QD in the Foretravel since new. Sometimes the generator would start and run for several hours and several days with no issues. Intermittently it would start and run 15 minutes and shut down and then restart, run for hours/cycles and days before it would shut down again. After several trips to Cummins/Onan and replacing the fuel pump, fuel control solenoid it did not fix the problem. Because it was not throwing any codes Cummins did not believe it was the control unit. Cummins finally did replace the control unit and it ran normally for a few trips and started again, but not as bad, but still with the symptoms. Thankfully all the repairs were covered under warranty. Mike found a company, "Flight Systems, Inc " that sells rebuilt Onan Control Units for half the price of the new Onan Control unit. He purchased a rebuilt Control Unit from the and replaced the Onan Control Unit and it solved the problem. No more Shutting down. I had a Mobile Technician come out and Verify that I was having and issue with the generator shutting down and the Extended Warranty approved the replacement of the Control Unit. I replaced it with a rebuilt Control Unit from Flight Systems, Inc. My generator has not shut down since the Replacement. Several other members who were having the same issue with their 10K/12.5K generators have purchased the Flight Systems rebuilt unit and the problem was fixed. This may not fix the issue with your 10K/12.5K generator, but it might be worth looking into. The Onan part number for the Control unit is 300-5961. The Flight Systems replacement part number is 56-5961-00 for their rebuilt unit. Cummins/Onan cost for their new Control Unit is $1000-$1200. Flight Systems price for their rebuilt unit is $695.00. The rebuilt Control Unit is sealed an epoxy material to prevent moisture contamination. Flight systems contact info is; https://www.flightsystems.com 1-800-333-9912 Thanks David sounds like I will have to get one. 51 minutes ago, Tom Cherry said: AMEN. You expanded what I know and several members have experienced. A friend sold his 3 year old, meticulously maintained 09 Camelot. Called me and said new owner has a Genny issue. He was providing support as David does. We three way talked to tech. He “made us smart”, but I was multitasking. Bingo. Real issue. He carried both new (Onan) and Flight (rebuilt). The new owner opted for Flight. Last I heard a few years ago…Genny working like a Timex watch. I talked once to a Flight tech support guy. Very smart and their website did or has a lot of great tech and troubleshooting help. I admit to forgetting the name “Flight” or I would have included. David has more insight and research and such and has facts, not shooting from hip. Thanks for filling in a lot and also confirming my recollection of this issue AGAIN….THE 7.5/8.0 are not as prone or hardly ever…so be aware if is the 240 models (10 & 12.5]. Thanks Tom will keepeveryone posted on my progress but sounds like I need a board from Flight Link to comment Share on other sites More sharing options...
philcarrell Posted August 17, 2023 Author Share Posted August 17, 2023 2 hours ago, Ivan K said: I have a 12.5 with Isuzu motor but the principal remains the same. As far as code 36, it is a catch all code for uncommanded shutdown (ie. the controller has no clue) and yes, is usually associated with fuel supply but not always. I got that same code 36 with burned out stator. But relax, that's not you case. Since your genny runs for hours before shutdown, it'll be difficult to wait and check for a specific reason this long. Any of the above responses are a possibility. But my question is, what is happening after the shutdown while you can't restart and have to wait an hour or so? Do you hear the pump clicking while priming or just before it turns over? Does it even turn over, likely yes, right? The pump is powered from the controller so it depends on your answer. It will start back up immediately with no hesitation. It just won't stay running as long as it does on first start. Really doesn't have to reprime. Link to comment Share on other sites More sharing options...
Ivan K Posted August 17, 2023 Share Posted August 17, 2023 12 minutes ago, philcarrell said: It will start back up immediately with no hesitation. It just won't stay running as long as it does on first start. Really doesn't have to reprime. Ok. I thought it wouldn't start for an hour, different story then. Link to comment Share on other sites More sharing options...
philcarrell Posted August 17, 2023 Author Share Posted August 17, 2023 52 minutes ago, Ivan K said: Ok. I thought it wouldn't start for an hour, different story then. After 1st shutdown will run an hor or so before shutting down. Link to comment Share on other sites More sharing options...
Donflem Posted August 17, 2023 Share Posted August 17, 2023 Mine has been doing that just shuts off but will start right back up. Wow you guys on this forum just amazing all the time I can honestly say buying my Dynasty and having the group of people on this forum is such a Blessing. I learned so much from all you guys. 👏👏👏👏🙏🙏🙏🙏👊👊👊👊 Link to comment Share on other sites More sharing options...
96 EVO Posted August 18, 2023 Share Posted August 18, 2023 1 hour ago, philcarrell said: It will start back up immediately with no hesitation. It just won't stay running as long as it does on first start. Really doesn't have to reprime. How many hours on the fuel filter? Link to comment Share on other sites More sharing options...
philcarrell Posted August 18, 2023 Author Share Posted August 18, 2023 56 minutes ago, 96 EVO said: How many hours on the fuel filter? Maybe ten. I changed it and nothing changed. Link to comment Share on other sites More sharing options...
David Pratt Posted August 18, 2023 Share Posted August 18, 2023 Let me expand more on this issue. The Cummins/Onan Control Units for the 10K-12.5K Generators are sealed in Epoxy and moisture/water will not effect their performance. The Harness plug is sealed when plugged into the control unit to prevent any moisture intrusion. Dirty fuel filters or low fuel is not the issue. there is a component on the control unit circuit board that is getting hot and causing the Generator to shut down. In most cases the generator will immediately restart and run. Mike's started to shut down and would not restart and run until it was shutdown for a longer length of time, probably waiting for the area on the circuit board to cool down. Five of the six Control Units that I have been involved with all showed signs of an overheating issue. Looking at the Control Unit after is has been removed and looking at the Circuit Board side that is Epoxied, there is an area on the board that is discolored about 1.5 square inches. On a couple of the boards the color was light brown and a couple of the other boards were much darker. Only one board showed no signs of discoloring and that board was from my Foretravel. Mike took a picture of the Onan CU that he replaced that showed signs of this overheating. If he still has it I will try to post it here. It leads me to believe that it may be a cold solder joint in that area, but that is just a wild ass guess on my part. The Control Unit is not difficult to replace takes about a half hour. Flight Systems Tech support is very good, but I could not get an answer from them what they find wrong on the CB they rebuild. I have been in contact with Cummins/Onan about what I have found and the fix. It will be interesting to see how far it goes with them. I am sure that there are many more coaches out there equipped with the 10K-12.5K QD generators with this issue and the owners have spent a lot of $$$$ replacing parts that are not the problem. Link to comment Share on other sites More sharing options...
philcarrell Posted August 18, 2023 Author Share Posted August 18, 2023 1 hour ago, David Pratt said: Let me expand more on this issue. The Cummins/Onan Control Units for the 10K-12.5K Generators are sealed in Epoxy and moisture/water will not effect their performance. The Harness plug is sealed when plugged into the control unit to prevent any moisture intrusion. Dirty fuel filters or low fuel is not the issue. there is a component on the control unit circuit board that is getting hot and causing the Generator to shut down. In most cases the generator will immediately restart and run. Mike's started to shut down and would not restart and run until it was shutdown for a longer length of time, probably waiting for the area on the circuit board to cool down. Five of the six Control Units that I have been involved with all showed signs of an overheating issue. Looking at the Control Unit after is has been removed and looking at the Circuit Board side that is Epoxied, there is an area on the board that is discolored about 1.5 square inches. On a couple of the boards the color was light brown and a couple of the other boards were much darker. Only one board showed no signs of discoloring and that board was from my Foretravel. Mike took a picture of the Onan CU that he replaced that showed signs of this overheating. If he still has it I will try to post it here. It leads me to believe that it may be a cold solder joint in that area, but that is just a wild ass guess on my part. The Control Unit is not difficult to replace takes about a half hour. Flight Systems Tech support is very good, but I could not get an answer from them what they find wrong on the CB they rebuild. I have been in contact with Cummins/Onan about what I have found and the fix. It will be interesting to see how far it goes with them. I am sure that there are many more coaches out there equipped with the 10K-12.5K QD generators with this issue and the owners have spent a lot of $$$$ replacing parts that are not the problem. David thanks for the education it leads me to believe that is the issue. You said 30 minutes to replace. Where is it located? I don't want to take everything apart if not necessary. Tried to get the repair manual off of Cummins but no luck. Link to comment Share on other sites More sharing options...
96 EVO Posted August 18, 2023 Share Posted August 18, 2023 If my memory is correct, I think I would have had the room to change mine with the front narrow strip of top cover removed. Of course, to get that piece of cover off, most of the larger top cover screws need to be removed, or a few just loosened. Link to comment Share on other sites More sharing options...
philcarrell Posted August 18, 2023 Author Share Posted August 18, 2023 Thanks will try that. Link to comment Share on other sites More sharing options...
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