John Haggerty
Birth Certificate
What are the sources of fuel in the oil? Just before this change I had a leaking fuel pump (changed the oil same time I changed the pump). Maybe there was fuel in the oil even after the oil change?
Oil Report
- Thread starter John Haggerty
- Start date
highest_vision
Reqistered User
Could be residual or maybe a bad diaphragm in the new pump. With the rdt, seems like you would have lower than the avg. Some early inj pumps would leak fuel to crank case if I remember right, or maybe the other way around...
Change the oil again and kee an eye on it and retest.
James
Change the oil again and kee an eye on it and retest.
James
DieselDon
Registered User
There is a small amount of fuel in almost every oil sample. If my memory doesn't fail me, it is acceptable to have 3 to 5% fuel dilution. Diesel is actually a pretty good lubricant, otherwise fuel pumps and injectors would fail rapidly. Most of it comes from unburned fuel in the combustion chambers.
The 1983 to 1985 6.9s had a problem with the injection pump shaft seal that would allow fuel to get into the oil. Stanadyne installed a double shaft seal and a weephole on the front bottom of the pump that solved the problem. Now if the seal fails, fuel leaks out onto the engine.
The fuel transfer pump also is designed to prevent fuel from a bad diaphragm from entering the crankcase by having the lever opening above a weephole
The 1983 to 1985 6.9s had a problem with the injection pump shaft seal that would allow fuel to get into the oil. Stanadyne installed a double shaft seal and a weephole on the front bottom of the pump that solved the problem. Now if the seal fails, fuel leaks out onto the engine.
The fuel transfer pump also is designed to prevent fuel from a bad diaphragm from entering the crankcase by having the lever opening above a weephole
