Just take the rocker arms out before you do anything else and all the valves
will be closed.
The likelihood that the head has had some machine work done in the chamber
is pretty small unless you bought the head from a racer. Measuring the
thickness with a micrometer or a very good caliper will give you a
reasonable baseline. A stock 2000 head is 4.528-4,530" thick.
If you do actually CC the head, you will most likely see variation from
chamber to chamber. This is because the valves can be sunk different amounts
due to valve seat grinding.
As far as the cam-center-to-crank-center distance goes, shimming the head if
it has been milled will restore that distance, as long as the cam towers
haven't been shimmed. The wipe problem occurs when you shim the cam towers,
because that increases the distance between the cam and the rockers. With a
milled head, you can shim on the bottom of the head or on the top of the
head, but you shouldn't do both.
Gordon Glasgow
Renton, WA
> -----Original Message-----
> From: owner-datsun-roadsters@autox.team.net
> [mailto:owner-datsun-roadsters@autox.team.net]On Behalf Of Daniel Neuman
> Sent: Thursday, November 10, 2005 11:49 AM
> To: 'Mark Sedlack'; datsun-roadsters@autox.team.net
> Subject: RE: CC'ing a head
>
>
> Hi Mark,
> Okay I'm following you except where do I smear the Vaseline exactly?
> I smear the Vaseline on the valve seats when the valves are up yes? Just
> enough to seal the valve but not gook up the combustion chamber?
> Then I put
> a light coating on the head surface to get the plexi to seal
> without getting
> any in the chamber. Okay I think I got it. I am still scared to turn the
> cam by hand though....How do I know its lubed? The machine shop
> that redid
> the head should of done that when they re-assembled right?
> Yep I have some burettes and syringes in my Halloween stash that I
> have been saving for just this occasion.
> I just discovered that I have tomorrow off so I want to try to do
> this then.
>
> Daniel Neuman
> Oakland CA
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