Leaky Lower Balance Shaft cover - M8 bolts not holding torque

[lemikson]

Finally found what the cause for my small, but annoying, oil leak from the Lower Balance Shaft cover area – just behind the Power Steering Pump Bracket.

The bigger M8 bolts that go at the cover front end cannot hold torque as specified (11 ft-lb and than 14 ft-lb). Three out of four can barely make 7-8 ft-lb. PO, or somebody before him, who worked on this car must had tried to get rid of the leak by simply applying more and more torque to these bolts, while all of them soaked in oil, and the thread simply started to give in. I guess I am just lucky it is not busted completely and oil is not just raining out : ). Red arrows are pointing to three M8 bolts that don’t hold torque. Red scribble line around the bolts shown on the LBS cover is the area where oil sips out/collects before starts dripping down.

I tried to seal all of it the way some members did it before to avoid removal of the Lower Cover. Applied Hylomar Blue to try to seal mating surfaces between the cover, washer and bolt heads. And then run bead of it all around the bolts along the leak path. Before sealing, cleaned everything with lots of oil cleaner, than brake cleaner, and than chased all the threads on bolts and in the holes, and then chased again, in order to remove as much oil as I could so I could get a bit more of the remaining toqrue from the threads…. Front end of the Balance Shaft is completely re-sealed with all new seals including Metal Collar!

Bottom line, it is again leaking. Not much, but I am lucky enough that the rest of my engine is completely dry, not even sweat marks from oil anywhere…. And, I can’t stand oil marks ☹

Anyone having any idea for remedy that is other then:

1. re-tap holes to M9 bolts (not sure if this is even possible with cover in place)

2. or, M9/M10 helicoil for which I would need to get the cover off.
I am trying to see if I can avoid removing the cover to fix this leak. And, no, engine is not going out anytime soon, fingers crossed.

[944 Ecology]

An M8 helicoil or timesert will be the proper fix.

If you are going to do it, why not do it right the first time?

[kdjones2000]

That or try some slightly longer bolts. I had to do that on at least one engine.