Diagnosing Blow by

[Glennman]

I've noticed a bit of blowby coming out of the vent under the engine ('02 Series 60). It doesn't do it when it's cold, and I am due for an oil change. Once it was warmed up, I had my grandson rev the engine while I watched, and the blowby didn't seem to change in villosity (I don't know if that means anything).

At any rate, I read that it can be caused by 1. A bad turbo; 2. The air compressor; or, 3. Piston rings/sleaves.

The engine doesn't smoke to speak of, it runs great, and I don't have any codes triggered.

Any ideas on how the trouble shoot this?

[luvrbus]

Blow by on the 60 EGR series is pretty common when they have miles on the engine ,most people don't worry about it ,the number 5 piston on EGR engines is usually the problem from all the heat from the EGR system.Have it tested if it is under 3 don't worry about it you're  not alone with the blow by on a series 60 ,it will live a long time with the blow by

[Glennman]

Thanks luvrvus! I'm not too concerned, as the bus runs great. I believe my 2002 12.7 series 60 is pre-egr though. Does that make a difference?

[luvrbus]

2002 was the 1st year for the EGR,  series 60 have ,I was always told it was caused by the piston design and open end rod on the Std series 60 the Perineum series 60-12.7 didn't have the problem with different pistons and closed end rods