I have taken the heads of and found that the o rings on the return oil ways have had shims / washers put under the o rings, i am guessing this is not normal ?? maybe someone has had oil leak issues in the past and has tried to pack the o ring out a bit, although this is only return oil under no pressure ??
Can someone help !! Should i have an o-ring recess on both the head face and the barrel face ? ( oil return holes ) as both recesses are approx 1.6mm deep = approx 3.2mm, the o-rings are approx 2.6mm therefore too small , hence why they have been shimmed up to make a seal, surely this cannot be right, has this engine been bodged up with different year parts or should this year have thicker section o-rings ( approx 4mm )
There is a 4Y stamped into the casting along with what looks to be a date code of 12/95 ,i guess dec 1995, could i have early heads on later barrels ??
The O rigs are supposed to fit without shims. I don't know if there were any changes in O ring size over the years. Maybe order O rings for both year engines and see what you get? There are two different size O rings, the one that goes around the bushing is different.
Quote from: howie on September 05, 2011, 12:10:51 PM
The O rigs are supposed to fit without shims. I don't know if there were any changes in O ring size over the years. Maybe order O rings for both year engines and see what you get? There are two different size O rings, the one that goes around the bushing is different.
Do you know if there should be a o-ring recess on both head and barrel faces ?
Sorry, I don't remember.
Looks like i may have 1995 SS heads on my 1998 bottom end,looks like they changed which face had the o-ring recess in over the years.