onan 4000 gen dies
I'm I the only one with trouble keeping 4000 onan running? at wits end! Things I have replaced 1- fuel filter 2- fuel pump 3- carburetor 4- replaced gas cap on motor home (Think...
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I've been fighting my Onan 4BGE spec G generator with the same problem. Runs for about 15 minutes then dies. I have hooked up a spark light tester and I can tell it is dropping spark.
I sent my Flight Systems voltage regulator and control board back to Flight Systems for testing. They were OK, but said VR was borderline. They gave me a good deal on one so I bought a Slip Stick slip ring cleaner and VR for $209. Would have been $70+ shipping for testing anyway.
I have recently replaced a faulty ICM with a used one; It could still be suspect. I tested my coil primary and secondary coils and they were within spec for resistance.
This weekend I'm going to clean the slip rings (currently measuring 80 ohms - should clean if higher than 30) and then install the new VR and the old board and see if it runs. If not, I will replace the ICM.
I already replaced my fuel pump, though I am pretty sure the one I replaced was fine.
Fuel tank is full.
There are 5 electrical components on my genset. Coil, ICM, VR, CB, Fuel Pump.
All are fairly easy to replace yourself. My fuel pump has a bolt that is very hard to get to when the genset is in the RV as the entire genset sits in a heavy steel "tray". The lip of the tray makes it impossible to access the bolt. I solved this by using a small hole saw to cut a hole in the lip which provides access to the bolt with a socket.
The trick with removing the ICM is to remove the two screws holding the bracket in place (do not drop them down into the genset!), and then you have to manually turn the engine until you find the one, single short fan blade and have it line up with the ICM slot. Then, and only then, can you remove the ICM. My genset uses a 3/8" hex bit on the gen head side of the generator to crank it over. Make sure you disconnect spark plugs first so engine can't fire and run and hurt you. It's easier to turn the engine if you take the plugs themselves out.
VR and CB are behind the front panel and are super easy to get at.
Coil is on the back top and a little harder to get to but not impossible on my RV with a hinged swing-down genset mounting.
Coil, about $100
ICM, about $100
VR, about $200
CB, about $200
Steve
I sent my Flight Systems voltage regulator and control board back to Flight Systems for testing. They were OK, but said VR was borderline. They gave me a good deal on one so I bought a Slip Stick slip ring cleaner and VR for $209. Would have been $70+ shipping for testing anyway.
I have recently replaced a faulty ICM with a used one; It could still be suspect. I tested my coil primary and secondary coils and they were within spec for resistance.
This weekend I'm going to clean the slip rings (currently measuring 80 ohms - should clean if higher than 30) and then install the new VR and the old board and see if it runs. If not, I will replace the ICM.
I already replaced my fuel pump, though I am pretty sure the one I replaced was fine.
Fuel tank is full.
There are 5 electrical components on my genset. Coil, ICM, VR, CB, Fuel Pump.
All are fairly easy to replace yourself. My fuel pump has a bolt that is very hard to get to when the genset is in the RV as the entire genset sits in a heavy steel "tray". The lip of the tray makes it impossible to access the bolt. I solved this by using a small hole saw to cut a hole in the lip which provides access to the bolt with a socket.
The trick with removing the ICM is to remove the two screws holding the bracket in place (do not drop them down into the genset!), and then you have to manually turn the engine until you find the one, single short fan blade and have it line up with the ICM slot. Then, and only then, can you remove the ICM. My genset uses a 3/8" hex bit on the gen head side of the generator to crank it over. Make sure you disconnect spark plugs first so engine can't fire and run and hurt you. It's easier to turn the engine if you take the plugs themselves out.
VR and CB are behind the front panel and are super easy to get at.
Coil is on the back top and a little harder to get to but not impossible on my RV with a hinged swing-down genset mounting.
Coil, about $100
ICM, about $100
VR, about $200
CB, about $200
Steve
