oil leak on rebuilt engine
 

rebuilt 2.7 with the intent of having not a single oil leak when finished. removed all studs from heads case etc.. tried to be very thorough, used a fine stone on all surfaces you get the idea. i used wurth flange sealant on the surfaces. after 1 or 2 hundred miles left side leak began between the cam housing and # 2 cyl head. pulled cam housing with heads then disassembled, noticed that there was no residual sealant between the cam housing and heads. the sealant had all squeezed out completely, no sealant between the surfaces, only around the perimeter. can anyone tell me what might have happened here ? the surface looks like it had no sealant applied. the sealant was borrowed from a friend, could it have been too old, or frozen at one time?

Please share what type of sealant. What torque spec did you use? Is the wrench a clicker (if so is it calibrated properly)?

Please keep in mind that the amount of sealant between the cam-towers and the heads is very very small and if done properly, might look like a very thing brown/orange film between them.

Now if you're sure there was NO sealant (ie no evidence of the excess squeezing out) then there's your leak.

99 percent of the time leaks there are from the rocker shafts. Yes that is just a guess but I believe it to be true.

-Andy

wurth sealant recommended torque waynes manual. don't know value now.

no rocker shaft leak. checked closely. for the record i'm 53 years old. Porsche trained mechanic 1972-1975, after that bmw master mechanic . Mercedes master mechanic. now golf course super.

Almost impossible to say what went wrong with your original assembly.

I used the following for sealing my 3.6 motor:

Outer Case Halves: Threebond 1104
Bearing Saddle Surfaces: Loctite 574
#8 Bearing (balancer end) O-Ring: Threebond 1211
Case Thru Bolts: Dow Corning 111 on Green Viton O-Rings
Flywheel Seal: Curil-T
Balancer Seal: Curil-T
Intermediate Shaft Cover to Case: ThreeBond 1211
Oil Breather Cover to Case: ThreeBond 1211
Cylinders to Case: Curil K-2 or ThreeBond 1211
Cam Towers to Cylinder Heads: Threebond 1104
Cam Chain Housings to Case: Threebond 1104
Cam Chain Housings to Cam Towers: Threebond 1104
Cam Chain Housing Cover to Cam Chain Housing: Threebond 1104
Gaskets: Thin coat of Loctite 574


This was from advice of various experts here on Pelican. So far it has worked well, with no leaks.



Kirk