Oil water coolant or fuel?

[steve604]

What would cause this in an '02 7.3? One injector is from #5 and the other is from #6

 

[Luke@MillerPerformance]

Would have to be a bad injector cup on those cylinders. What does your coolant look like?

 

[steve604]

No loss of coolant, no fuel, no oil. The motor uses a lot of oil, doesn't leak, doesn't blow blue, compression is awesome, o-rings have been changed many times.

 

[Brad.S.19]

Bad injector cups, Check the overflow for diesel as the fuel system operates at a higher pressure than the cooling. Get a cooling system pressurization unit, clean all the injector bores really well no oil or fuel as it makes the test more difficult. pressurize the system to 12-15 pounds and see if coolant appears in the suspected cups but I would check them all. It is hard to see have a decent light source if nothing comes of it pull a coolant sample and have it tested. If you pull a sample let it sit over night and see if any separation occurs.