Guys this is a long story but I will try to make condense it. My brother in law has a 98 Ford F450 that is their farm service truck with a 7.3 PSD. About 2 years ago the engine finally blew. 300k pretty hard miles. Anyway he purchased a 2002 7.3 from a salvage yard with 65k miles and let it sit until this spring when we decided to swap them out.


Well, we realized theses motors aren't exactly the same (as you guys probably already know). The motor mounts weren't the same so we ended swapping the motor mounts as well as the older oil cooler and old drivers side exhaust manifold back over to this 2002 PSD among some other components in the turbo piping and older turbo.


When we did this we decided to install new gaskets and o-rings in the oil cooler and end housings. We buttoned everything up and started it up.


I was really pretty amazed at how easily it started. It hit and run a little rough for 10 seconds or so then evened out and ran pretty well. No smoke at all. I ran it about 45 seconds, checked the oil and it looked good. Ran it another minute or two and oil looked good. It was after the third time of running a few minutes that I noticed the oil looked real milky. I didn't start it again. and noticed the coolant was lower in the reservoir and the oil was about a quart over full and real milky.


I don't notice oil in the coolant just milky oil. But I can double check tomorrow if that is a very important aspect. Like I said it runs pretty well for sitting for a long time and it doesn't appear to smoke at all so I don't think it is getting in the cylinders. I have to think we may have damaged an o-ring when we reinstalled the cooler.


What should we have used for lube on the O-rings when reinstalling the cooler? I think we used grease. I wasn't there when they did it.


Any help would be greatly appreciated. This is my first experience with a PSD and one of the few I have with a diesel at all.

 

I used Vasoline on the o rings when I rebuilt the oil cooler. Use a lot of it. Some have reported a mixture of Vasoline and engine oil.

 

Also, unless the superduty oil cooler was bad, you didn't need to swap it out. I have an 01 oil cooler on my 95 motor because my old oil cooler was missing the pressure relief valve and the newer style oil coolers have those c-clipped in which is better. It's not a bad idea to replaced the o-rings on whatever cooler you used so if you do go back to using the newer oil cooler, it may be a good idea to replace those o-rings as well.

From everything I read, most likely the oil cooler o-rings got damaged upon installation, so you'll want to take that down and check them out.

 

After I typed that....I thought about it. I wasn't there when they reinstalled the oil cooler, they may have used the newer one. I will check.


I think we are going to remove it. (It looks like a real PITA now that the engine is IN the truck, perhaps we can get it out from underneath or through the wheel well) and check the O-rings. I will report back with what we find.

 

This turned out to be a cut o-ring during oil cooler installation.

 

Glad you figured it out!

 

I'm happy to hear that it was something simple.

 

And how was the work? easy or a PITA