Thread: Changing Filters - ISUZU 110

Mmmm. Sounds like a small air leak.

Top of fuel tank is above the sedimenter and maybe fuel is being fed in by gravity when full. One possibility is the pressure from the pump is being relieved from the source of least resistence and with a full tank the fuel instead of air would be that source. When the fuel drops and requires more pressure to lift the fuel from the tank, it sucks air from a leak instead.

Maybe the o rings at the top of the cav unit where the bolt head sits need replacing. I suppose this would not be replaced often as it involves unbolting the cav unit or unbolting the floor.

I found the air leak in my cav type unit by putting it into a bucket of water and pressurised it with a compressor, the bubbles showed the leak. The air was leaking from a bung at the top.

Small air leak, probably on the CAV element. Been there.

John

I have to agree that it will be a small airleak.
I had a similar but much more annoying incident after haveing the pickup out of the tank. Ran out of fuel every 70ks or so. Prime and away it would go. Only happened when tank was below 1/2. Tightened all the connections and it was fixed. They weren't loose.