Expiremental OM617 build
Expiremental OM617 build
i have been having an issue lately with excessive smoking at idle. i did a valve adjustment and re tested the injectors to make sure they were not dripping also changed the glow plugs and inspected the pre-chambers. while i had the plugs out and the injectors i noticed that #1 seemed slightly wet with oil this combined with some slight residual pressure in the coolant expansion tank after sitting for a day confirmed my thoughts of a failed head gasket. it has been smoking for a while and getting steadily worse so i finally decided to pull the head and swap in the new head thats been ported along with the new cam. while i was pulling the head bolts i noticed a few were wet with oil on the threads but dry by the shank two were also covered in soot.
you can see there where it failed the #3 and 4 also had similar failures just not as bad.
the pistons are pristine with no visible erosion or anything. the bores are great too ~.004" wear step with cross hatching still clearly visible. i still need to surface the ported head and have a three angle valve job done. i have been holding off of doing that work until right before i put it on so as to limit the possibility of damage in storage or transport. while i had the old head off i set it next to the new ported one to show the difference. its quite dramatic especially
im also considering swapping in a new compressor wheel in the HE221W.
dimensions are 189mm inducer and 258mm exducer. this plus some slightly larger valves should help it breathe.
but seriously i should have the new head on and running before too long. i already have the new gasket and bolts all i need to do is get the machine work done and spend a weekend working. ill be interested to see how much of a difference it will make in power without any fueling changes.