Ok this is my first post hope I get it right. I bought a 1995 F-350 7.3 Dually with 248,000 miles for my soon to be 16 yr old son. It seems stock except for the cat converter being eliminated. I did the cheap injector clean that was posted the other day. That seemed to make it run much smoother (Thanks Good Post).

When I start it it runs very nice and smooth (not even a miss). After getting out on the highway and up to temp (Good and Hot) it loses power drops down to about 40mph and shuts off soon after. If you sit on the side of the road about an hour and let it cool to the point you can put your hand on the engine it will start with a lot of cranking. It still has very little power but will limp home.

I noticed an oil leak from the lower right side of engine at about mid block. I can not see it because of the cross member from underneath and no chance of seeing it from above. When backing out of the driveway the drips are about 3 inches apart.

From what I have read here and from listening to the newer F-350 owner that stopped to help is there multiple fuel pumps and is there one that requires some type of "High Oil Pressure"? I am not sure the two are related but it seems to me that everthing on these engines are related.

Looking forward to some good responses,
Allen

 

The injectors use high Pressure oil to open.the leak would be a good thing to fix first.also crank sensor are a known bad thing in these trucks.

 

Most likely the oil leak and the dying when warm are two different problems. The dying is is most likely the IPR orings. That is a very common problem on a truck with that many miles. Here's two links that will help:

https://www.ford-trucks.com/forums/8...h-or-ford.html
https://www.ford-trucks.com/forums/8...-this-one.html

 

Oh and the guy on the side of the road was wrong. There is one fuel pump, in the rear of the valley, under the turbo, and to oil pumps. The LPOP (Low Pressure Oil Pump) which is like any other oil pump in a typical engine, and the HPOP (High Pressure Oil Pump) which supplies oils at up to 3000 psi to the injectors. The HPOP is at the very front of the valley.

 

Ok what does IPR stand for? Do I need to do something to the HPOP?

 

There are many things that cause the truck to lose power and die. However you say that it takes a lot of cranking to get the truck started after it dies. This tells me that it is likely a high pressure oil leak or fuel starvation. The usual high pressure oil leaks are failed seals on the IPR(injection pressure regulator) valve, or worn injector seals. The IPR valve is located bottom left(as sitting in the drivers seat) corner on the back side of the high pressure oil pump. It will have a 2 wire connector attached to it. The easiest things to do first though is change the oil and filter if you dont know when it was changed last or has been a while. These engines like clean oil. Also when was the last time the fuel filter was changed?

 

I just changed the fuel filter and the bowl is very clean especially after doing the diesel kleen trick. Don't know about the oil. Does this engine really hold 14 quarts? What could be leaking on the passenger side of engine?

 

I would change the oil and use a reputable brand such as mobil delvac, rotella, or even motorcraft(my preference). The oil needs to have an additive package that helps reduce foaming. If you run extended oil drain intervals the more the additive package is depleted. The only things that can leak oil on the right side of the engine is the valve cover gasket, oil pan, and dipstick. The valve cover gaskets are unlikely, they are a reusable design and also expensive. The dipstick tube runs down to a fitting in the oil pan. I have seen this leak on a couple, the kicker is the you need to have the oil pan off to reseal the fitting. The oil pan cant be removed unless the engine is out of chassis. Now before you think oh my god what did I get into.......My experience with these engine is that sometimes where the oil drips from is not even close to where it is leaking from. I would wash the engine off and clean up the mess than check for the leak. On a side note I have seen oil leak from the exhaust manifold before, either from wetstacking(oil or raw fuel from cold cylinders this is caused by extended idling), or a worn engine or malfunctioning injector. The exhaust manifolds did not use a gasket from the factory, however one is available for service.

 

Ya'll have given me some I ideas to try. I will post back my results. Thanks so far.

 

The most likely cause of the oil leak is where the dipstick goes into the oil pan. There is a large bolt around it. Clean up the area and tighten the bolt as best as you can and see if it stops. A most likely cause of the engine stopping could just be that its low on oil. When that happens the hpop doesn't get oil to fire the injectors, then the motor quits. A drip every 3 inches is quite a bit.

 

dieseldoc beat me!

 

Does it really take 14 quarts to change the oil?

 

Yep. 14 quarts. Maybe a little more. But I use 14.

 

Mine always seems to take 15 quarts. I use Rotella 15W-40.

 

I saw on here ya'll were talking about a regular oil change would not change the HPOP. Do I need to do something extra?