Rear camshaft seal

[At1Maverick]

I have a very bad leak coming from the rear of the engine on my 95 SR, and it seem like it's coming from up above, I'm assuming it's coming from the rear cam seals. Has anyone had a chance to replace theirs, I just wanted to know if I have to take off the cam the rear cap to accomplish this? Any help would be appreciated. Thanks in advance

 

[Jay Ayala]

Tell us about your engine. Is it 3.0 SOHC? Is it a 3.0 DOHC? Is it a 3.5L engine?


Sent from my iPad using Tapatalk

 

[At1Maverick]

Oh,so sorry. This is a 95 Montero SR with a DOHC 3.5l. And I meant to ask as well, is there anything else than that rear seal that would leak oil? I have the valve cover gaskets and have the rear seal already.

 

[nwoods]

My 98 with the 3.5L SOHC motor leaks a fair amount where the oil cooler lines feed into the engine block. Have you checked that area?

 

[Jay Ayala]

The only other thing I can think of that is high enough to cause a leak in that high of a spot other than the valve cover and rear cam seal is the head gasket it self. If you are removing the valve cover anyway to add the gasket, I would suggest you check the torque on the cylinder head. I recently learned that cylinder head bolts are one time use items because they sort of stretch once they have been initially torqued. If you ever have to remove a head and put it back on, using the original (now elongated) bolts, you may run into one of two situations, #1 You may bottom out the bolt in the bore. This would give you a false torque reading causing you to think it is torqued to specification when actually it is not tightened up properly. This may cause an oil leak at the back of the block. #2 Or they may bottom out and slowly (this could take months) the bolts would back themselves out. Again, causing the head gasket to not seal properly causing a leak scenario.

In both cases, you may have oil & water mixing. You may have those symptoms already, if so, buy a new set of cylinder head bolts along with new cylinder gaskets. If you go that deep, you may as well do all new timing and water pump and all that other maintenance.

 

[mapper]

My research was all about the 3.5 SOHC but as far as I recall the DOHC is similar in regard to the seal...your own research will have to confirm. It always helps to google "pajero" and/or "shogun" as well "montero" when googling for repairs on these.

From my research the cam seals on the back and front are a fairly standard leak on these motors and very likely to be the cause of your leak. On the back it is a simple o-ring on a plug (a few bucks from the dealer) that can be replaced without removing the cam itself. Anecdotal evidence (web searching) says it can be replaced without removing the intake or valve covers but obviously there is easier access if either are replaced.

 

[At1Maverick]

nwoods- I've checked everything as far as oil lines, and other possible passages where oil would come from, and it's pretty much just coming from the rear of the head on the driver side.

Jay Ayala- I've done the timing belt/water pump front seals and all that stuff a week after I got the Monty, that was about a month ago, cuz atr first I thought it was actually coming from the front crank seal, I even thought for a hot minute that it was the rear main, but I had my old lady start it up as I slid underneath it, and saw the stream of oil, coming down, just couldn't quite see where exactly. But it is above the head/block mating surface, so I doubt it's a HG issue, and neither my oil or coolant is milky, thank God.