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Alloy cylinder head

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M

mgtf328

Jedi Hopeful
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My BJ8 has a Rawles motorsport alloy head and puts puffs of blue smoke out when it starts from cold, valve seals I expect.

I've been stoking myself up to change them and now the "virus" seems to be creeping back again I have no excuse other than I have never worked on an alloy head before. I tend to make sure that nuts are tight enough! So I'm a little bit afraid that I might do some damage by overcompensating and not tightening them enough or stripping some threads. I also suspect that the torque on the head and manifold bolts should be a lot lower than the Bentley manual indicates.

So can anyone tell me what the head and manifold bolt torque's should be. I've googled it and come up with nothing so far.

Any other advice on working on alloy heads would also be welcome.

Thanks
AJ
 
I do not think there would be a problem with OEM torque that being said did it come with a head gasket and new head bolts. There is a rotation to tighten bolts and a recheck after so long. What about the lower end new rings ; cast, chrome, and how many steps cut on valves two or three. And fall back on Rawles. Is block true? heating and cooling of different metals can cause unknows problems. Best of luck tell us what Rawles said and what you find. One for all ! all for one ! Madflyer
 
I have a Denis Welch aluminum head and torqued the head nuts per Bentley. The only things I worry about are the spark plugs. Be sure to lube or anti-seize those threads.
 
the temperature of the head when retightening is important. Alloy heads are usually done cold so check this with the manufacturer.

Danny
 
There is a way of replacing valve seals without removing the cylinderhead. You might want to consider that, if you're reluctant to remove the head . . . .
 
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