onan 4000 dying
My Onan 4000 runs for 15-20 minutes then dies. Wont restart. 3 flashing lights at the panel. Gas tank is half full. ?
Forum Discussion
OK this is what I did to replace the pump:
First disconnect shore power and negative cables from House and Chassis batteries.
In the picture below the pump and filter are visible below the heavy white wire with the red insulation on the connector. The fuel line enters the side of the generator box and is clamped onto the filter. Crawl under the RV and remove the clamp, pull the hose off and plug the hose to stop gas from draining. I think I used a short piece of 1/4 inch dowel.
In order to get at the pump, which is below the control board, disconnect the heavy red wire from the solenoid and the connector that has the multiple white wires. Remove the two Torx screws (visible at the bottom of the picture below) that hold the control board to the generator box. I think I had to unbolt the solenoid as well to get the control board out.
Once the control board is out of the way, the pump is accessible. The pump is held in place with one Torx screw through a foot. The other foot fits into a slot in the bottom of the box. Below is a picture of the old pump and filter assembly. The discharge hose that goes to the carburetor is still attached.
I replaced both the pump and filter and used a screw clamp on the pump discharge hose. After putting everything back together, the generator ran fine. I did have one issue though. I didn't get a good seal on the pump/filter connection and had a slight drip of gas. Fortunately it wasn't necessary to disassemble everything again because the filter can be removed from the outside. I removed and plugged the fuel line at the filter inlet and used a 9/16 deep socket to unscrew the filter from the pump. I put a small amount of pipe dope on the male threads of the filter, being careful to keep the dope away from the end, so none would get into the pump or carburetor.
It has been 7 years since and no more leaks or trouble with the pump.
Below is a picture showing the part number for the filter.
First disconnect shore power and negative cables from House and Chassis batteries.
In the picture below the pump and filter are visible below the heavy white wire with the red insulation on the connector. The fuel line enters the side of the generator box and is clamped onto the filter. Crawl under the RV and remove the clamp, pull the hose off and plug the hose to stop gas from draining. I think I used a short piece of 1/4 inch dowel.
In order to get at the pump, which is below the control board, disconnect the heavy red wire from the solenoid and the connector that has the multiple white wires. Remove the two Torx screws (visible at the bottom of the picture below) that hold the control board to the generator box. I think I had to unbolt the solenoid as well to get the control board out.
Once the control board is out of the way, the pump is accessible. The pump is held in place with one Torx screw through a foot. The other foot fits into a slot in the bottom of the box. Below is a picture of the old pump and filter assembly. The discharge hose that goes to the carburetor is still attached.
I replaced both the pump and filter and used a screw clamp on the pump discharge hose. After putting everything back together, the generator ran fine. I did have one issue though. I didn't get a good seal on the pump/filter connection and had a slight drip of gas. Fortunately it wasn't necessary to disassemble everything again because the filter can be removed from the outside. I removed and plugged the fuel line at the filter inlet and used a 9/16 deep socket to unscrew the filter from the pump. I put a small amount of pipe dope on the male threads of the filter, being careful to keep the dope away from the end, so none would get into the pump or carburetor.
It has been 7 years since and no more leaks or trouble with the pump.
Below is a picture showing the part number for the filter.
