I got called to work on a cat th560b today for a no start problem. After checking it over, found fuel system full of air. Bled it at the injectors, and got it cranked finally, and it runs good, but it’s still getting air from somewhere. If you shut it off and restart, it’s a bear to start, and has air in lines again. The fuel hoses look new from the electric pump back to tank. Wandering if the electric lift pump could be getting air somehow? The pump never shuts off if you just turn the key on, and I thought on these, the pump would prime up and shut off, and only kick on when cranking or running. Anyone have any experience on tgese? Looks to be a little 4 cylinder Perkins engine, has 8700 hrs Thanks
replace the pickup tube in the tank. It can rust and develop pin holes in the pickup tube as well as there is a plastic screen on the bottom of the pickup tube which I remove. On my third machine with this issue. Took a lot to figure the first on out