Timing cover flatness

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GavinL
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Timing cover flatness

Post by GavinL »

My timing cover was leaking substantially after I replaced the chain, between the lower two bolts ( the crankshaft oil seal wasn't showing any signs of leaking) .

I removed it and checked its flatness on a surface plate and I can get a 15 thou feeler under it between the bolt holes virtually all the way round, which I assume is due to it having been over tightened in the past. Is it practical to address this by carefully punching the bolt holes so that it is flat? Has anyone achieved this?
philthehill
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Re: Timing cover flatness

Post by philthehill »

There is no problem with punching the timing cover bolt holes flat.
There has always been a problem with the 'A' Series timing cover gasket sealing.
In the end BMC produced a strengthening strip to place on the lower half of the timing cover flange to keep the distortion to the minimum.
Here is the modern equivalent:-
https://www.ebay.co.uk/itm/124759869625 ... SwUIletp6I

paul 300358
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Re: Timing cover flatness

Post by paul 300358 »

At the present time it scrap, if you try to straighten it the worst that can happen is it will still be scrap. But, you may save it.
MCYorks
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Re: Timing cover flatness

Post by MCYorks »

It may be worth a try if the distortion isn't too bad and you can get it flat enough. Of course the easy fix is another decent cover, but personally I prefer to repair rather than replace when possible. I had a similar issue with a tappet chest cover. The previous owner had tried to stop a leak by simply tightening the bolt more and more till it distorted the cover :roll: So I had to straighten it before fitting a new gasket.
midget
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Re: Timing cover flatness

Post by midget »

https://www.ebay.co.uk/itm/124759869625 ... SwUIletp6I

+1--just fitted one, and it works , and I did not use the extra fixings
John
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