Cam cover stud removal

[zigzagsky]

Disaster.

Putting my car back together and replacing the leaking cam cover gasket, I was tightening up the cam cover dome nuts (using a torque wrench set to 10 foot pounds and one has sheared off (unfortunately one that doubles up as a cam fixing stud). I had previously read that the nuts should be tightened to no more than 12-15 foot pounds but have now read that 7 is the correct figure.

Pretty fed up making a stupid mistake but now looking into replacing the stud and how to do it.

I assume it can be removed with the head in place but what would be the best method to remove it?

Brian

[Mich7920]

Hi Brian,
Unscew the 2 nuts at the both side of the bearing stud.
Remove the bearing
On the one that the head is brokend, screw 2 nuts on the lower thread .
You'll tighten the 2 nuts on themself.
Unscrew the lower nut and the stud is going to unscrew simply.
Mich

[mgcjag]

Hi Brian....can you see any of the stud..where has it sheared off...can you see any of it....do you now have the cam cover removed..a photo would help...Steve

[zigzagsky]

Stud is just proud of the cam cover (so the bit that sheared is the upper threaded part).

Picture attached.

Brian

[zigzagsky]

Hi Brian,
Unscew the 2 nuts at the both side of the bearing stud.
Remove the bearing
On the one that the head is brokend, screw 2 nuts on the lower thread .
You'll tighten the 2 nuts on themself.
Unscrew the lower nut and the stud is going to unscrew simply.
Mich

Thanks Mich.

The nut on the broken stud undid quite easily. The one on the other side is pretty tight - worried I might break a 2nd stud if I apply too much force!!

Should they be very tight?

[Mich7920]

Looking your photo I think you have enought thread to do waht I explained you with the broken stud.
To answer your question.
Normaly the good torque is 15lb.ft which is not very hight.
Mecanicaly I don't think you could break the stud in uncrewing the 1/2" nut, it has this size throughout it's lenght until into the cylinder head. If some thing happenend it could be that the stud unscrew from the head.
Use a good tool, especially not an adjustable wrench, rather a pipe wrench. You could put a tube to have more torque. Do this slowly, it's obliged to come.

[zigzagsky]

Thanks Mich for inspiring confidence.

I'll have a go tomorrow using the 2 nuts as you suggest once I've removed the 2nd one.

Replacement stud & chrome dome nut (actually 2 just in case) ordered from SNG.

Brian

[Mich7920]

Brian, just have a Look at closely to something.
Compare the lenght of the stud when the can cover is in place and the depth of your dome nuts.
I don't think you broke the stud with a too hight torque but rather the stud was at the bottom of the nut and not yet flush to the cam cover. Hope it could help you for tomorrow...
Good job
Mich

[abowie]

Thanks Mich for inspiring confidence.

I'll have a go tomorrow using the 2 nuts as you suggest once I've removed the 2nd one.

Replacement stud & chrome dome nut (actually 2 just in case) ordered from SNG.

Brian

What Mich suggests will work fine.

Try cleaning out the bottom of the hole with a bit of wire and some WD40. If you think the stud is sitting a little high run a tap down the thread in the head; it is 5/16" /UNC. If you are still unhappy grind a little off the top of the stud where the domed nut fits.

Retorque the cam bearing cap to 15 lbft. You may need a long 1/2"AF socket to do this properly. It is important that the cap is properly torqued down as this affects the valve clearance.

I use standard paper cam cover gaskets. I spray both sides with blue Hylomar. I torque the nuts up to 4 lbft initially, then to 7 lbft if it leaks.

[christopher storey]

Make sure before undoing the cam bearing that you have turned the engine so that neither of the cams adjacent to the bearing are opening valves . That way you minimise any bending load on the camshaft

[zigzagsky]

Ok, well that was easier than I thought...

2 nut idea worked a treat and in fact the stud was quite easy to remove so I do wonder if maybe it wasn't seated fully in the first place and that the chrome dome nut did indeed 'bottom out'.

Just got to wait for the replacement parts now.

Thanks for the advice chaps.