Cam Cover Bolt + Spark Plug Cover Bolt Leaking Oil 1999 V70 T5M

[Catbeeshark]

Hi everyone, first post here.

I recently bought a 1999 T5M (somewhat rare option with the factory manual transmission) in California and drove it to my home state of Wisconsin. When I picked the car up it had no visible mechanical issues and seemed to perform fine. The previous owner had done a lot of their own work to the car including replacing the PCV system, timing belt, and rebuilding the head in the last 20k miles, so I took the chance and bought the car to drive the whole way back to Green Bay.




My luck held up for the whole trip, I drove pretty careful with it being a 26 year old 135k mile car. By the time I'd reached home (~2,600 mile trip) I noticed the car had lost a significant amount of oil and was making a loud lifter ticking sound. Pulling the spark plug cover i noticed a significant amount of oil had pooled in the wells for the plugs, accumulating a significant puddle and drowning 3/5 of the plugs. Also, even more distressingly, one of the front side bolts for the spark plug cover seemed to be letting oil pass through it while the car was running. Checking all of the cam cover bolts next I found that one of the bolts at the far outside of cover which sat flush would freely spin and could even be removed.



The threads inside are soaked with oil but doesnt spray oil while running the way the spark plug cover bolt does. the threads themselves don't appear stripped but when inserted into place the bolt does not seem to grab anything. My next step is probably going to be pulling up the cam cover and checking all 40 bolts for thread issues. I'm assuming this is some issue resulting from the cam cover being resealed incorrectly when the previous owner did his repairs. hoping that I can just Helicoil this bolt (7Mx35mm) and reseal the cam cover. If anyone has encountered something like this before and has advice I'd appreciate any tips. I've never had to do any major engine maintenance on one of these cars before but I've researched a little bit of the procedure on Youtube with Robert DIY's videos being a huge source of help.

Thanks for reading, any help is hugely appreciated

[abscate]

That’s a great score!

That’s a later build 99 with mechanical lifters, not hydraulic

You aren’t going to believe this, but I have exactly the same problem on my 99 T5M. One of the cam cover bolts is stripped and gushes oil.

I’ve tried:

Sealer on bolt
Epoxying bolt washer to cover
Silicon plug

And what’s left is:

Lift the cam cover and helicoil the thread.

[Catbeeshark]

thanks for the response! good tip about the mechanical lifters. funny that we're both in the same boat on this one. I have the helicoil kit ordered and im popping the lid tomorrow to get a better look at it, i'll post back when i have more pictures to share.

[abscate]

I’ve thought about retapping threads but here is the problem, the cam cover is a clearance hole, of course, and the threads are in the top of the cylinder head itself. I’m not happy about drilling an over size hole into the cover and head

I even though of JB welding a hole plug. Not thrilled with that , either.

[abscate]

Made good progress on this today.

I finally fixed my window on my Miata New Beetle so now I can move to the next car wart, which is this one