Any M62 gurus here?

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bfons
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Any M62 gurus here?

Post by bfons »

I’m having a problem with one of the 11 bolts on the valve cover. Just spins.

Anybody ever wrestled this beast?
Brian

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1984 Graphite M635 - Project Graphite - Sold
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1987 L6 Black/Lotus White - My Queen has a new home
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Pod
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Re: Any M62 gurus here?

Post by Pod »

bfons wrote: Sun Jul 21, 2019 4:09 am I’m having a problem with one of the 11 bolts on the valve cover. Just spins.

Anybody ever wrestled this beast?
I had a similar problem recently ( though not on my E31). It was a stripped thread on the fastener, although in your case I think it’s more likely to be in the casting ☹️.

I removed it by exerting pressure underneath the fastener with a screwdriver, whilst slowly turning it until the thread bit. I don’t know which of your bolts it is, but if you can’t get on it, maybe you could try welding something to the top of the bolt to facilitate the lifting phase of removal? Good luck!
Drew
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Re: Any M62 gurus here?

Post by Drew »

+1

it'll be stripped threads in the alloy head casting (or cam bearing cap, depends which bolt is spinning). The alloy on the M62 heads is very like brie, and it's easy to over-torque these bolts when trying to eliminate oil weeps from the cam cover

I have fixed a stripped thread on a bearing cap using a thread insert. If you need to remove a bearing cap, take care to rotate the engine to ensure the cam is unloaded in that area, as the cam is hollow and snappable under stress (I understand)
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