Caterpillar D4 7U blowing diesel out one of the two tubes on left side front of motor

Tube on the left connects to the filter tower (top) vent valve and tees with the transfer pump seal cavity. Appears you have a leaking outer seal packing in the transfer pump. Replace both outer and inner packing seals.
Other tube drains the fuel injection pump housing if the injection pumps are leaking.

Thanks for the reply Old Magnet.So is this a hard fix?Do you think Caterpillar will have the seal kit or is there an aftermarket parts place.I will be headed out to the tractor this week to try to find the transfer pump.Thanks again

Cat has the two seals that get packed in around the shaft drive--not very expensive. Hardest part is finding someone with the packing drive tool to set the packing---the pump unbolts easily from the engine block --there are also a gasket and seal there also

Thanks dpendzic...will look for the pump and pull it off...But I got to thinking maybe I ran it low on fuel.It started to run bad when I started to pull a hill.So I wonder if the fuel ran to the back of the tank.(tank behind seat).Could it of pulled some junk out of the tank?Maybe plugging up fuel system somewhere?Would that make that drain pipe blow diesel out of it?

Thanks dpendzic...will look for the pump and pull it off...But I got to thinking maybe I ran it low on fuel.It started to run bad when I started to pull a hill.So I wonder if the fuel ran to the back of the tank.(tank behind seat).Could it of pulled some junk out of the tank?Maybe plugging up fuel system somewhere?Would that make that drain pipe blow diesel out of it?

Normally it wouldn't make the seal leak but i suppose if a lot of rust/grit/sand got to the transfer pump it could affect the seal. Disconnect the fuel line to the transfer pump and make sure you have good fuel flow. power loss is a sign of not getting enough fuel so plugged line or very low fuel may have caused that. have you changed the fuel filters lately?

I just changed the fuel transfer pump seals last week. My 7U is a very late tractor (43,000 series) and needed one lip seal and one o ring seal, and the new housing gasket. It is easy to get the fuel injection housing off. My tractor has a pony engine with the engaging clutch to the right of the fuel housing. If you lift the end of the housing up while pulling it off of the studs, it will slide right out and clear. If you have direct start it will be easier. It probably weighs around 80 pounds so keep a tight grip on it. Do not allow the diesel engine to turn over while the pump is off or turn the pump shaft behind the lip seal. You will lose the timing. Pull the injection lines off and keep them in order. Going back in, good luck on the getting the nut started on the middle back stud. I used a pressure washer to clean behind the pump housing before doing the work. It's tight but a 9/16 on a swivel u-joint will do the trick. I was able to slip the lock washer in with my fingers. The inside bottom nut is a bit tricky too. Bleeding the injectors on the diesel was easy. Good luck.

Some how the topic changed from transfer pump leakage issues to injection pump/filter tower seal issues.

:noidea::noidea::noidea: stay with the transfer pump like om stated, its the issue, been there done it a couple times without the special seal tamping tool i'll add. fuel tank rust running thru the t pump usually causes this issue. this is why i and others use a filter prior to the t pump. good luck.