The Diesel Stop banner
1 - 13 of 13 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
Recently (3 weeks ago) purchased a early 03 6.0 with 248xxx miles. Very nice clean truck all around. Mostly highway miles according to previous owner. A couple years ago it was studded, deleted, air raid cold air intake, turbo back exhaust, and glow plugs.

Truck runs, sounds, and drives great. When i got it it had new oil and it was at the full line. I have since put around 1000-1500 miles on it and checked the oil the other day and it was way over full and smelled of diesel. Drained it today and took out 5 gallons and 1 qt. Filled it up with new oil, filter, etc to just under the max line (14.5 qts). Drove about 60 miles today and it is a little over the max line and smells of diesel again.

It has a small oil leak coming best I can tell from the back side of the passenger side valve cover. Maybe from being over full, not sure.

Since I got the truck I have noticed the smell of diesel occasionally when I come to a stop.

The truck also have a SCT programmer and the guy said it was in performance mode. I was getting horrible MPG (8-10) normal driving so played with a few other tunes with not much results. Put it back to stock and was getting 16mpg at 70-75mph on highway no AC. Recently got a custom economy tune from IDP and hasn't really improved any.

There were 2 times after getting fuel that the truck took a couple attempts to start, other than that no issues starting right up cold or hot.

Truck has plenty of power and very minimal blow-by (I can put the cap upside down and it doesn't blow off)

I have not noticed any power loss or missing or anything like that. Truck actually runs really good and has a lot more power than my old 7.3.

So with a little bit of history that I know, What would be the most likely suspect of the diesel getting into the oil? The research I have done I am thinking injector seals. My plan so far is to take the truck to the shop monday and have them put it on the computer and do the balance test and see what that says. Then buy complete oring set for injectors and open it up and see if I can find the problem and put new orings on the injectors.

Any others ideas? Any other seals, orings, etc that I should replace when I am in there?

Thanks for the help.
 

·
Registered
Joined
·
5,322 Posts
Could be injector seals or it is a cracked head. The fuel passage drilled lengthwise in head is at top of injector bore and when it cracks toward intake it can leak into engine. Some head cracks leak into coolant when the crack is towards exhaust side of head.
 

·
Registered
Joined
·
5,430 Posts
I would bet on an injector seal or a bad injector
 

·
Registered
Joined
·
5,449 Posts
Early 6.0L injectors had problems with internal leaks that allowed fuel to leak from the injector body where the upper body screws into the lower body. I am assuming this truck has one or more original injectors in it but theoretically any year OEM or reman injector could leak there. I had several of these come through my shop with high crankcase oil level caused by an injector leak.

There is a way to diagnose this. Acquire a Ultra Violet leak detection light (search the internet as there are inexpensive choices) and a small bottle of UV dye formulated for oil based fluids. It will not damage the fuel system.


  1. Remove the secondary fuel filter cap and remove a little fuel. Pour in about one ounce of the dye and reinstall the filter cap.
  2. Remove the valve covers.
  3. With a scan tool or jumpering the fuel pump relay run the fuel pump to cycle the dye through the injection system.
  4. Using the UV light inspect the injector areas for signs of the bright dye.
If there is a leak the dye will become visible. It should be very obvious when you see it. Service as required.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #5 ·
Thanks for the replies. I was wondering if there was some way of using a dye and light to help find it. That's great. I really have no idea on the injectors if they have ever been replaced or stock or what. So another question I've been looking at injectors online and there are so many options from remans for $1k a set of 8 on up. What are some good ones and what are ones to stay away from?
 

·
Registered
Joined
·
5,430 Posts
IMO the only injectors to buy are OEM injectors, unless you are going after modified ones for higher horsepower.

You can join FordParts.com and specify AutoNation White Bear Lake as your primary dealership and get them for a little over$200 each (and shipping is reasonable).

I would not go with cheap injectors.
 

·
Registered
Joined
·
5,125 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #8 ·
Also how exactly would you jumper the fuel pump relay? Not finding much info on the Internet about that
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #9 ·
Took it to the shop today and everything looked good other than injector 6 was showing weak on the balance test. So going tomorrow to get a new injector, full set of orings, dye etc and hopefully figure this out
 

·
Registered
Joined
·
6 Posts
I've been here.. bought the cheap injectors from Pensacola Diesel (DO NOT BUY FROM THEM) and had an injector dumping diesel in the oil.. bought 8 remans from Ford and did an oil change.. I now have one of the internally cleanest 6.0 motors you'll ever fing and it runs great too lol
 

·
Registered
Joined
·
5,125 Posts
Wow, motor flush!
 

·
Registered
Joined
·
5,125 Posts
Yeah, what works for one usually isn't so good for the other.
 
1 - 13 of 13 Posts
Top