I have a caterpillar dc6 and the transfer pump overflow pipe is pissing out fuel I’ve had 2 new pumps aftermarket still leaks totally new fuel lines new rebuilt injector pump I give up now any ideas
I'm gonna go out on a limb and ask "What's your machine's serial number?" Should help the experts here look up which bits you have so they can provide you an educated guess (diagnosis) on what's happening. Without knowing your machine configuration, it's just a plain old guess.
Do you have a t handle bleed screw on the top of the pump left open by chance?
Added to what @LCA078 posted above some photos of your fuel transfer & fuel injection pumps might also help. There were quite a few different injection systems on machines of that era.
17j2877
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47j2877
Pretty much what I was thinking. From what I understand it will be either a D333C or a 3306 engine with the compact injector pump. The transfer pump has it's own inbuilt relief valve that simply diverts fuel from the outlet side to the inlet side. The only pipe in the fuel tank is the outlet pipe. There is only the air bleed tap and associated pipe on top of the filter housing where fuel can get out of the system other then a failure of something like a cracked housing. I have seen that little round tap come loose and fuel starts coming out the pipe. Unfortunately in the photo it has been cut off so it cannot be pointed out.
Not showing what we need to see....area around filter!!! Bleed valve flow and transfer pump leakage flows to the drain off the bottom of the accessory drive housing. If transfer pump is not the culprit then check the bleed valve needle and seat, they have been known to leak. (bad seat, bent or damaged needle.) Engine is a 49V, 3306 for that s/n.