ONAN 7.5 Diesel Generator

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mike2011

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OK, here I am back again begging for help. I have an 07 Phaeton that has a 7.5 Onan Quiet Diesel generator. I have never had a minute of problem from this generator until now. Recently we were using the generator and I had the generator slide in the front of the coach slightly opened. As we were getting ready to leave, while the generator was running, I slid the slide back into the coach. The generator immediately stopped and would not restart. I ran the diagnostic and the code is 19, GOV ACTUATOR FAULT. Which seems to also indicate the possibility of a short or open circuit. I suspect that when I slid the slide back in I may have created a broken wire. I've read where some have experienced this as a result of a broken wire around the GOV control. Can anyone tell me where that is located on the generator or if you have other ideas of things to check. Thanks.
Mike
 

Utclmjmpr

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  On the curbside front corner of the enclosure you will find the gang plug where the house wiring connects to the generator wiring,, I would look around there, maybe became dislodged?>>>Dan
 

mike2011

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Utclmjmpr said:
  On the curbside front corner of the enclosure you will find the gang plug where the house wiring connects to the generator wiring,, I would look around there, maybe became dislodged?>>>Dan
I looked at that area very good. I took off the maintenance cover on that corner and checked all connections at the terminal block---all good. Following that wire bundle from the generator to the coach, after about 2 feet there is a cannon plug connection. I took it apart and checked connections and cleanliness ---- all good. Still giving me the 19 code and will not start. Thanks for the suggestion.

Fixed quote
 

Utclmjmpr

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Roll underneath and at the center rear is the battery connections and the fuel connections, I would remove the battery cables,, clean and reattach.  Then push down and hold the lower part of the rocker starter switch for a few seconds, this is a work around for most causes,,( worth a try), then try again.>>>Dan
 

billwild

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Mike, here is hoping you can fix this one yourself. My genie quit working at the switch on the dash, and I finally had to take it in. Turns out it was the same problem you are having, broken wire in that bundle that leads to the genie. Unfortunately I was paying for their time to find the problem and it was expensive. Sure was nice to have it back working though. Perhaps if you pulled the genie all the way out on the slide and had someone push the dash switch while you moved the wires around you may get a connection, and track down the broken wire


Bill
 

mike2011

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I checked, cleaned and retightened battery connections on the rear of the generator. Still a NO-GO at this station. The generator will turn over when I depress the start button, both inside and on the generator. It just wont start. I appreciate all the advice, I'm checking everything that is mentioned.
 

Utclmjmpr

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At the bottom of the box, open the trap door,(where you would go to drain the oil), you will find the fuel pump with two wires connected to it using spade connectors. Remove and test each wire (with a multi meter) see if you get current when someone pushes the start switch.. If the pump is toast obviously it won't start.>>>Dan  ( Pump is available at NAPA stores)
 

Gary RV_Wizard

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If it cranks, you are down to air or fuel delivery as the problem.  Well, maybe the glow plugs too. The Onan diesels can be very hard to start if the glow plugs aren't functioning.
 

mike2011

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Today I went into the lower compartment where the oil filter and fuel pump are located. I took apart the spade connectors and put a multimeter on them and had my wife press the start button.  It would not turn over at all in that condition. I suspect it has to complete the circuit through the fuel pump to turn over. However I reconnected the spade connectors and tried again. This time it turned over but again wouldn't start. I cracked the fittings going into and coming out of the fuel filter. I had fuel at both connections as I pressed the start button but still didn't start. I have gone all over the gen looking for loose wires. Everything seems to be in order. When I depress the start button it pauses like it always has while the glow plug heats up and after 5-7 seconds turns over but will not start. Does anyone know where the glow plug is located? Or how to check it? I still think it goes back to a wire somewhere because as I pushed the slide back into the coach, the generator simultaneously quit running. I have thoroughly checked wires outside the generator enclosure. Any ideas? Thanks
 

mike2011

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Utclmjmpr said:
Did you check for a kink in the fuel line? Your going to find it's something stupid.>>>Dan
I did check for a fuel line kink. Everything good there. Plus I get fuel coming out of the fuel filter. My next step is to take the top off the generator cover and check it out. I've done some reading and it says the governor is located at the top back corner. I'm going to check wiring there since I started with a 19 code.
 

mike2011

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Drum roll please. I fixed it!  I took off the top cover over the generator, about 12-14 bolts, and took a hard look inside. Sitting in the back, driver side, corner is a black plastic cover that is over the governor. Coming through the very top are two male spade connectors. A quick glimpse looked normal but when I reached back and wiggled the wires the right wire had popped off and was actually beside the connector. I reattached and tried the gen, it ran perfectly. Thanks for all the advice. 
 

Utclmjmpr

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I don't know how much "time" is on your generator,,but now would be a great opportunity to inspect the water pump BELT for wear and possible need to be replaced.>>>Dan
 

mike2011

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Utclmjmpr said:
I don't know how much "time" is on your generator,,but now would be a great opportunity to inspect the water pump BELT for wear and possible need to be replaced.>>>Dan
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I've got about 1300 hours on it. I've already put the top back on it. Is that all that needs to be removed, just the top?
 

Utclmjmpr

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With top off you can see and access the belt on my HDAK model,, your mileage may vary.>>>Dan (Mine has 2650 hrs. on it.>>>)
 
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