The leak is probably come from the top of the engine draining down on the starter

 

There is fuel on top of the engine in the valley. It only leaks while the engine is running. I can not visibly see a leak from up top... Looks like it may be coming from under the exhaust side of the turbo.

 

90% of the fuel system is in the valley. There is a fuel line fitting on the back of the pass. side head by the turbo also check all the rubber fuel lines that connect the fuel bowl and pump

 

Ok looking on the back of head but can't see a line... Do you have to pull the turbo off to get to it?

 

Ok looking on the back of head but can't see a line... Do you have to pull the turbo off to get to it? I looked from top and bottom.

 

Your fuel leak could be coming from several different spots on the motor you need to clean up that fuel in the valley real good the get a good light and maybe a mirror to see where it is coming from all the fuel that leaks in the valley will drain through a hole at the back of the valley under the turbo and drain onto the starter and transmission.

 

The fuel line or fitting you are looking for is right at the back of the head follow the metal fuel lines under the turbo back to the fitting these fittings have a rubber seal in them that will dry out from the heat of the exhaust and start to leak.

 

What's the best way to clean the valley? Anything you recommend?

 

When I had the issue used lot of paper towels with a long screwdriver. Not as bad as you might think if it's not a really bad leak. Key here is just to try and dry up stuff so you can see where the leak might be coming from. Think I used about 1/2 roll of paper towels.

Most common point is the fuel pump itself. There is a weep hole in the fuel pump, like a water pump, but very hard to see .. so clean the area under the fuel pump the best you can and using a mirror look under the fuel pump body for leaks.

Needless to say there are many points for leaks but the better you clean it up the easier it is to find. After all my work (replaced pump and hoses) I still had a leak and the picture below shows the sensor I had to replace. It was very difficult to find this leak because it was just a drip .. drip every second or so.

Sensor is called "fuel filter vacuum sensor" or something like that ...

 

Thanks so much for your help... I really appreciate it guys will clean it up tomorrow and post my findings...

 

Ok huge puddle under fuel pump after drive around... Seems as though I will be replacing it next. Any tricks known for an easy swap out?

 

Before you go changing a pump make sure all the hose clamps on the fuel lines going to the pump are tight and check to see if any of the lines are bad.

Also check to see if the banjo bolt (big bolt) on the back of the pump is loose it's a 1 1/4"

 

Fuel pump replacement

This service is not difficult when working on a Federal-emissions F-series. The intake Y-pipe and fuel filter housing need to be removed first. Then, using a 1 1/4" box wrench (having two different wrenches works best because of differing angles on the box ends give you a wider working range) or socket on a flex-head ratchet, loosen the banjo bolt fitting at the rear of the pump. Take care not to drop or damage the steel sealing washers. After removing the banjo bolt, remove the pump mounting bolts and lift the pump straight out of its hole. If the pump seems stuck, use a rolling-head type pry bar (lady-slipper, duck bill, crowsfoot) to pry it up straight. Pulling staight up will prevent the pump push rod from catching and falling back down into the engine requiring engine removal to retrieve the rod. On California-emission vehicles the banjo fitting is too far under the turbo and fuel line damper to reach with a wrench and access is restricted for using a socket (you may get the bolt out, but good luck getting the it back in). In this case and with the Econoline due to its body design, it is necessary to remove the turbocharger to remove the lift pump instead of the fuel filter housing. In all cases, when installing the new lift pump, lube the o-ring on the pump shank with dielectric grease and start the banjo bolt a couple of threads before installing a tightening the mounting bolts. Again, take care not to damage the sealing washers. Once the pump is secured to the block, tighten the banjo bolt to 40 ft/lbs.

 

Funny that you say thY about the "banjo bolt" at the back. That is where it looks like the fuel is coming from. If it is directly in back mine looks like it has 2 lines connected to it. Can you tighten this without affecting the lines themselves? This is my first diesel truck I appreciate all of your help with these issues.

 

you can try to tighten it just don't go strong arm on it. The two lines that your seeing is all made together