After reviewing many of the posts here regarding the potential sources of oil leaks on the 7.3L diesel (mine's an '01 model), I never came across what I eventually found to be source of my leak.

Word of caution: Do not remove the downward facing plug on the bottom of the HPOP, Ford's TSB for this repair says removing it will damage your HPOP $$$. The one you can remove is on the back, near the fuel bowl drain.

My leak started out slow and within a week or so had turned to a torrential downpour that nicely waterproofed the entire underside of my truck. After a brief search, I found that the "end plug" as Ford calls it on the back of the HPOP (high pressure oil pump) used to have an O-ring on it, but now only scraps of an O-ring remained. It was much easier to spot the oil running from the 18mm plug on the HPOP when the engine was cold (rather than spraying vigorously when the oil was warm).

I acquired the new O-ring kit from the dealer (part # 2C3Z-9G804-AB), and hope to have the problem resolved in short order. Anyways, just wanted to put it out there that this End Plug can be a source of the problem, since it doesn't appear it's discussed much and if it happened to mine...

 

samething happened to me

 

Funny you should mention it. I just picked min '03 up from the dealer who replaced the o-ring in mine. I just got back from a trip to TX and noticed a puddle. I didn't have time to explore so I needed an oil change anyway and took it it. They got it fixed and it was covered under warranty except for the $100 dedectible (which was probably about what it cost anyway ). Anyway, it was no biggie and it's fixed.

Have a good one,
John

 

As mentioned above I had hoped this would solve the leaking problem quickly, which it appears to have done...however...the truck now runs very rough at all rpm's.

So here's my thought, probably not enough oil in the HPOP because it all drained out when I replaced the end plug...do you guys agree?? If this is/could be the case, where do you fill/prime the HPOP??

Thanks for your input everyone!!

Jeff "I wish I could just watch the BCS Championship" Knight

 

You can just "drive" the air out of it. It just takes a little while for all the air to work out of the rails.

 

Thank you very much for your input Miller. I thought it was gradually sounding better as it idled but didn't want to take the chance of letting it run on like an off-balance washing machine if it wasn't going to help. As it turns out, it worked through the rough running condition in a couple miles and all is good.

Now I just hope to find that the oil falling onto the ground is just the residual oil from the previous leak. You guys are awesome, thanks for your support of ford-trucks.com

 

Thanks for the info, Redsundevil. I posted a link to this thread in the Common Mods/Maintenance thread, as I figured folks might find it handy when browsing that in the future.

 

Redsundevil,

I have a slow oil leak that I suspect is the same thing, as it's definately not the lines.

How does that plug come out? Is there a snap-ring, or is it a threaded plug?

Anything you can tell me will help me get the tools together.

Thanks,

Pop

 

Another good leak is from the high pressure oil pump. It's a high pressure hose with a (not so) quick release fitting.

 

It just takes a regular socket to get the plug out. I had the exact same problem. It saved me from paying some deisel shop 1100 bucks to replace my HPOP.

 

Pop,

The end plug on the HPOP is an 18MM threaded bolt that looks like a larger version of any drain plug you've ever encountered. As you'll likely see in the $29 o-ring kit you buy from Ford, the plug should be torqued to 25 ft-lbs upon reinstallation (along with some loctite).

I had considered trying to locate some generic o-rings that were the same size, but now that I've seen the o-ring that comes in the kit, I don't think I would advise someone to go this route. The rubber in the new O-ring kit seems to be a much harder compound than most run-of-the-mill O-rings I've seen. So spend the $29 here (assuming this is the problem and hopefully you won't have to scrub your driveway every week.

 

I used an O ring from the Hpop o ring kit form DFuser.com.

 

Redsundevil.

Thank you for the very comprehensive reply. That's what we like to see around here!

Welcome to this forum. It seems that there's NOTHING that will go wrong with any of our trucks that somebody else hasn't already been through and solved.

You've arrived at a VERY good place for a 7.3 owner to be!!

Pop

 

Redsundevil,

how much oil can I expect to come out of the plug as it looks like I have the same problem? Will it be easier to wait for an oil change?

'01 Supercab 7.3PSD Dually XLT 121K

 

A small amount came out when I changed mine, but it was very minimal.