I've never done this, but I've heard you can do this with modeling clay
as well.
With valves closed, fill the chamber with clay until level. Remove clay
and place
in a graduated cylinder or whatever you have to measure with.
Volume is volume, right?
- Loren
'68 1600 converted to U20 w/5-sp
'70 2000 now parting out (anyone need anything?)
-----Original Message-----
From: Mark Sedlack [mailto:msedlack@neo.rr.com]
Sent: Thursday, November 10, 2005 12:57 PM
To: Datsun Roadster Mailing List (E-mail)
Subject: Re: CC'ing a head
Daniel,
You'll need a piece of 3/16 or thicker plex, large enough to cover the
combustion chamber. Dril a 1/4" hole, centered. Rotate the cam by hand
( be sure its lubed, and a piece of wood as a lever helps) until valves
for chamber you're checking are closed. Fixture, prop, brace, whatever,
to get the sealing surface level. Get a graduated cylinder, a burrette
with hose and valve or a very large syringe ( might have one in your
Halloween
stuff??)
Smear a thin coating of vaseline around the valve seats - just enough to
be sure they are completely sealed. Wipe away excess. Use 100 cc of
isopropyl alchohol, tinted with a drop or two of food coloring. Smear a
thin coat of vaseline on the sealing surface of the head, close to, but
not right up to the edge of the chamber. The idea is to get the
vaseline seal, without getting any in the chamber itself.
Press the plex down onto it, twisting slightly to seat it. Carefully
pour or drip the alcohol into the 1/4" hole, till the level comes up
flush with the bottom of the hole. The clear plex lets you know when
its full with no air. Subtract the number of cc left in the burrette
from the starting 100cc, and you're done.
Mark Sedlack
ZROC
Cuyahoga Falls OH
66 1600 http://www.mildevco.net/chevypowereddatsuns/
77 280Z http://www.mildevco.net/chevypowereddatsuns/
----- Original Message -----
From: "Daniel Neuman" <neuman@radonc17.ucsf.edu>
To: <datsun-roadsters@autox.team.net>
Sent: Thursday, November 10, 2005 1:25 PM
Subject: CC'ing a head
> Hello All,
> I need to actively start to put my engine back together. I had the
head
> re-done but I know its too thin. I want to cc my heads so I can
figure
out
> how thick of a head gasket I need to bring the compression down to
about
8-1
> and to restore the correct valve train geometry. Has anybody ever
done
this
> before and would you please give me some guidance.
> I understand that you fill the combustion chamber up with a measured
> amount of light oil and that it helps to put a piece of flat glass
over
the
> head to know when you have really exactly filled the chamber.
> So how do I do this exactly? I imagine I will have to figure out a
way
to
> mount the head to my workbench and to get/keep the head perfectly
level. I
> am also going to need to turn the crankshaft to close all the valves.
How
> do I do that when the head is off the engine and sitting on my
workbench
> (without screwing everything up??).
>
> Thanks,
> Daniel Neuman
> Oakland CA
> 69 2000
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