Time to ask my question, I have a 2000 c-70, ran perfect until an oil leak started on camshaft cover, next to torx bolts, car has never been hot but showed a camshaft sensor OBD code, no miss but oil leak, my do it at home certified mechanic said he d tackle it, replaced camshaft sensor, then tackled oil leak , this is when trouble started, he took camshaft cover off cleaned checked and re installed, he didn t replace bolts with new ones, I understand this is a must do also he didn t use an angle guage when re torqueing, it immediately began mis firing, he checked coil packs, plugs wires and O ring around plug, now it still is leaking oil at torx bolts on top of camshaft cover and mis firing, also shows camshaft sensor code, he has the tools and checked coil packs injectors, switched coil packs around to look for any improvement. My theory is camshaft cover needs to come off, replace all bolts, use angle guage to re torque. This car ran fine until he took camshaft cover off, he s pretty good, certified but not on Volvos, this is a different animal, does any one have any advice? thanks in advance. Does this camshaft cover require new bolts, are these head bolts? Do the bolts on camshaft cover have torque specs?

 

The cam cover bolts are not torque to yield bolts and can be reused. He probably doesn't have the tools to set the timing when taking the cams out. Also, he probably didn't use the proper sealer between the head and cam cover. And a cam sensor code is not usually a bad cam sensor.

 

I recommend you take the car to a shop that knows how to work on Volvo's. Either a dealer or independent Volvo shop.

 

Just following up on my original question, I know now the camshaft cover bolts don t need replacing unless bad, also its kind of a big deal to take cover off, special puller and press to put it back on, also need to take off upper motor mount, special liquid gasket sealer, bolts torque to about 12 ft. lbs. and if you take this camshaft cover off its real easy to screw up camshaft seals. What I m really curious about is what is the purpose of the 20 t40 torx bolts, they are 1/2" long and keep oil from flowing out onto the camshaft cover, I have 4 that are leaking oil.

 

Those are removed to check valve clearance. Worthless, since you can't adjust clearance without pulling the cam cover. You can use some thread sealer on them.

 

These cam covers do not have gaskets like most cars have, those bolts help seal the cover to the head.

 

Those bolts do not seal the cover to the head.

 

Some other bolt on the top of the motor? I guess I need to see a picture of what he is referring to.

 

The 20 T40s. Not all have them

 

Ten on each side of the camshaft cover, they are inspection bolts for checking valve clearance, the bolts are inside the camshaft position on both sides,

 

Thank you for your reply, you have answered and probably solved my problem

 

Thanks for everyones input, I found out what I needed to know, the heck with those T40 torx bolts, they ll never leak again lol.