Oil Coming From Cylinder/Case Junction

[JTO]

Hi Everyone,

I was cleaning the underside of my 911 since the girl is basically put up for the winter. As I was inspecting and cleaning I noticed a little oil weeping on the case that looked like it originated from the cylinder and case junction, on the passenger side only. The drivers side is dry. As some of you may know, the motor was rebuilt by MM about 1.5 years ago (before I was a Pelicanhead). It has over 6000 miles on it. There is a little oil coming from the oil return tubes and valve covers, but not enough to drip on the ground, just enough to show some oil wetness, and I'm not really concerned about these oil leaks. But, do I need to be concerned about a little oil coming from the cyliner to case junction? Should I retorque the head studs? The studs are APR with Timecerts in the case. The head studs have not been retorqued since the rebuild. Any advice would be appreciated! Thanks!

Troy

[Wayne 962]

Hmm, a tough one. Normally I would retorque the heads, but not knowing the condition of the engine - might add some concern. This area is really not a leaky area, unless the head studs become loose.

-Wayne

[JTO]

Hi Wayne,
Thanks for responding. Assuming the engine is in good shape since it was recently rebuilt (by MM, yikes) is it normal procedure to retorque the head studs on a 2.7 with Timecerts, etc?

Thanks again,
Troy

[john walker's workshop]

were the cylinder bases on the case trued in a mill? mag cases, particularly 2.7s get serious wear there. there is often a visible notch where the cylinder has been working on the case, usually because of the 2.7s "loose head due to pulled studs" problem. all the mating surfaces need to be on the same plane to stay tight and seal properly.

[JTO]

Hi John,

Thanks for the reply. When the motor was rebuilt, I asked that the case be trued, timecerted, and linehoned if needed. MM said they do this on all of their Mg case engine rebuilds, if needed. I have to assume that this was done. Unfortunately due to the reputation of MM, it may not have been done. John, should I try retorqueing the heads? The quantity of oil is very minor, just enough to we the passenger's side of the case.

Thanks for your input.
Troy

[john walker's workshop]

if the case was inserted, a retorque would probably be ok. 23#. you're asking for a pulled stud if it hasn't been. but then you're damned if you do, and damned if you don't.

[JTO]

Thanks John. We'll see how brave I am feeling on that particular day!

Troy

[Wayne 962]

Originally posted by john walker's workshop
were the cylinder bases on the case trued in a mill? mag cases, particularly 2.7s get serious wear there. there is often a visible notch where the cylinder has been working on the case, usually because of the 2.7s "loose head due to pulled studs" problem. all the mating surfaces need to be on the same plane to stay tight and seal properly.

Most rebuilders do not true up the case (like detailed in my book). If I were to place a bet, I would bet against this having been done on this case.

-Wayne

[JTO]

what would you do? Knowing the oil quantity is very little (not wet). Would you just drive the car and keep up on maintanence or would you strive to find the cause and repair it? I need to know if I should obsess about this issue or let it go.

Thanks,
Troy