Air in Volvo Engine

[peterbeale]

I have a Volvo MD 17 C engine. After 4 to 6 hours running the engine stops because of air. It is easy to bleed and it starts right away. I have searched from the fuel tank to the injectors and cannot find an air leak. It seems to like to stop just before docking. Any suggestions of how to locate the leak?

[Jason Flare]

No real suggestions but I found an air leak at a hose clamp and barb on the 3/8" fuel hose. I was snugging up the hose clamps and the hose came off.

It was the type of barb that had a mushroom head rather than three or four barbs and the clamp was squeezing the hose on the mushroom head and after a couple of hundred hours, and me tightening it, it worked itself off the mushroom head.

[NoTies]

Suction leaks can be a real bear to find. If you can access the bottom of the pick up tube, try hooking an air line to it with about 1 bar of pressure then do the soapy water test along the entire line.

[rwidman]

If you can't find the leak, just re do every connection between the tank and the engine. If that doesn't help, you have a hole in a hose or tubing. Replace them.

[Lepke]

Leak will probably be between the tank and the lift pump. After the lift pump it's pressurized and would leak fuel. Isolate the fuel line and pressurize it with air. Add a gauge and see if it holds pressure. Usually I can hear the air leak and have bad hearing. Look for places where the line can rub a hole, loose or broken fittings.
As a last resort, don't dock and it may never fail.

[jamhass]

bad o-ring in filter?

[jannw]

look first at your filter ... most likely source of a small air leak