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chimp007_uk
07-07-12, 06:51 PM
I have a C20XE engine that I'm planning on stripping and rebuilding for my track car. I have limited knowledge on the engine, so intend of stripping it all down and getting it cleaned and honed etc.

I was looking at the cyclinder head this afternoon and noticed that the threads for the cam cover fixings have been pulled out around the top. When you put the cam cover on there isn't wnough thread for the fixings to screw into.

http://i40.photobucket.com/albums/e229/chimp007_uk/c05ee8c4.jpg

Anyone got any ideas of what I can do?

Cheers
Chris
David2005
07-07-12, 07:06 PM
Just helicoil it?
chimp007_uk
07-07-12, 07:23 PM
Didn't thing you could helicoil m6, but just looked it up and I stand corrected. Just presumed that it would be too small.

Looking at all the threads, there's probably only 5 that are ok...

I don't have a thread gauge, does anyone know what pitch the cam cover fixings are?
MK999
07-07-12, 08:02 PM
Find somewhere that does timeserts rather than helicoils, they're far far better.
chimp007_uk
07-07-12, 08:42 PM
Cheers Mark, not heard of Time Serts, but looking at the price and the fact they're American I think I'll give them a miss.

Either way still need to find out the pitch of the cam cover fixings.
Pistol Pete
07-07-12, 08:45 PM
More than likely be M6 x 1.25.
brainsnova
07-07-12, 09:14 PM
There's thread inserts that are m8 exterior m6 interior.
mowgli
07-07-12, 10:55 PM
m6 coarse is actually m6x1.0

why not simply redrill & tap them all for an m8 allen key???
MK999
07-07-12, 11:19 PM
Cheers Mark, not heard of Time Serts, but looking at the price and the fact they're American I think I'll give them a miss.

Either way still need to find out the pitch of the cam cover fixings.

Wurth deal with time serts, if you can get it over to me I'll stick one in for you.
Pistol Pete
07-07-12, 11:27 PM
m6 coarse is actually m6x1.0

why not simply redrill & tap them all for an m8 allen key???

Would the bolt heads be too big to fit inside the cover?
mowgli
08-07-12, 12:25 AM
Would the bolt heads be too big to fit inside the cover? go to a decent fixing supplier & get some small head bolts
hotrod
08-07-12, 12:30 AM
Bit of a long fix that just helicoil it job done! :)
chimp007_uk
08-07-12, 09:43 AM
I think the 8mm shank will be too big for the holes in the cover. If the pitch is 1.25 I can't seem to find a helicoil kit to do it... Ordered a thread gauge so will find out.

Mark, its more than one, there only looks to be 4/5 that are ok.
MK999
08-07-12, 09:47 AM
I'm sure I can get it done for you, I'll have a word with work and see if I can do them after hours for you, most likely have to cover the cost of the inserts though, think they're a few quid each.
mowgli
08-07-12, 10:27 AM
I think the 8mm shank will be too big for the holes in the cover. If the pitch is 1.25 I can't seem to find a helicoil kit to do it... Ordered a thread gauge so will find out.

Mark, its more than one, there only looks to be 4/5 that are ok.

all gm m6 coarse threads are 1.0mm.
chimp007_uk
08-07-12, 12:43 PM
Cheers Mowgli! I'll ordered a m6 helicoil kit...

Mark, I'll have a go at helicoiling them, if I was back at my folks I'd run it down to you, but a 200mile round trip (twice) is bit keen.