Onan 7.5 mdje

[Trojan]

I had a strange one Saturday. I started the generator and it ran for about 35 minutes and started to run ruff and quit. I started checking today and I did the obvious. I changed the filters. Nope no go. So I removed the fuel exit line and found no fuel. Great a bad lift pump. I removed it thinking maybe a bad diaphragm. Nope The diaphragm was good. What the heck. I started looking and to my surprise when I turned the pump top over, the exit check valve was just lightly pushed into the hole UPSIDE DOWN. Now, how did that happened? I don't know. I checked the valve and reinstalled it with a driver and upset the edges of the hole so it won't come out again and reassembled the pump. Then reinstalled the pump and the generator took right off running. What a brake. Saved a boat buck there.
BILL

 

[Boatsb]

Bill the pump is about $350.00 I have the same issue. I have been too gentle to the valve in the housing so I re set it 4 times. The last one included a small bit of Aluminum Foil around the valve to hold it tight and then a few good whacks to seat it. I put 10 hours on it since and hope to never have that problem again . Good luck on yours.

FWIW the first 3 times I did it I had the unit o the bench. The installation is now done and the access is better than originally planned because of that.

 

[Trojan]

Thanks for the warning. The next time I will use loctite bearing stuff. I didn't know this was so common.

BILL