Weird-Leaks Fuel after Hauling heavy load

[whitediesel80]

I noticed that my truck leaks fuel after hauling a heavy load down the highway 70 mph. It appears to be running down the back side of the block an dripping on the ground on the passenger side by the front leaf spring by the oil pan. I'm 98% sure it's not engine oil because everything is dry around the oil pan. Then the leak stops after a couple of days normal driving.

[POWERED SPARKLESS]

Are you sure it fuel? Make sure you get a good smell next time. Sorry I'm not much help.

[ajpu1983]

There is a 6mm hex head fuel rail plug on the rear of each cylinder head. They have O-rings on them and I have seen a few blow but they leak constantly most of the time.

[Hank]

What are you driving? My 2001 7.3 leaks oil from the turbo pedestal when I get on it hard. Leaves a small puddle of oil in the driveway and then "heals" when I take it easy. I already have the o-ring kit ready for the replacement. Look down in your valley with a flashlight. I have been told that if there is oil in the front of the valley it is probably your HPOP. If it is in the rear of the valley only, then it is most likely your pedestal.

[dannyboy950]

There are a number of places in the valley you could be getting fuel or oil or both leaking. Why it shows up after a long run or pulling a load is it probably is a hair line cut in an o-ring. When engine is cold or running low speeds the pressures and viscosity are low enough that a good seal isd being made.
The longer you run the hotter it gets and thins out also the pressures of both fuel and oil are higher.

The best way to check is clean up the valley so you have a good clean test surface and then put some ultraviolt test dye in the oil and fuel tank.
The test kits are avaiable from most parts houses.

I like to jack up the front of the truck so it will drain better. Put a large pan wider than the engine or spread oil dry underneath a thick layer cause yer gonna make a mess. I then take a hand pump garden type sprayer and put a gal of diesel, then pump up and spray the worst of the buil-up away. I then use some brake clean to wash the rest off and dry things up a bit.

Dealers choice as to which to test first or both at same time. I prefer one at a time. Run it till it gets good and hot and check with the UV light and glasses. All available from most parts houses. Rinse and repeat untill ya find it.

Good luck.

[whitediesel80]

THANKS TO ALL! I'll gettit DONE!