bad blow by
 

Hey guys , I'm having a problem with a '99 7.3l . Getting bad blow by , enough to carry over quite a bit of oil with it . Slight difficulty starting , rough idle when cold and progresses to a knock when warm . I'm suspecting a collapsed piston , what do you think ? Tks

what have you done to the truck recently .............did you by chance adjust the valve lash?

maybe a broken ring

Have you ever had Propane hooked to it?

Any updates??

might just have your fix
 

i had the exact same problems with my 02 7.3 and it was one of the injector seals. its impossible to find out which one but u can get all of them replaced for around $700. You can expect it about every 150,000 - 200,000 miles. hope this helps.

Check your fuel in the filter housing. If it looks like it's contaminated by oil, evilstevel hit the nail on the head. Good luck.

Did you ever figure out what it is, I'm having some blow by too

Any luck??

Closing due to a one time post