Hi Peter,
Haven't heard from you for a while. I guess my thinking behind just
replacing the chain is that I'll avoid having to purchase another inlet
manifold gasket (about $200NZ). If I just replace the chain it'll cost me
about $180NZ as I have the front cover gaskets already.
If the cam is replaced it will cost about $270NZ for the cam, $80NZ for the
lifters (SB Chev I think...), $200NZ for the gasket, and the valve springs
should really be replaced as well at a cost of about $200NZ ( I think).
That all adds up to about $750 more than just doing the chain.
I probably think about this too much, but it seems to me that if I have the
engine that far apart why not recon the heads (I have a spare set to prepare
in advance) as well. That would take the cost to about $2000NZ (the full
gasket set is $320NZ)to get the heads done etc.
At that stage I'd have an engine with a good top end but with a short block
in an unknown state (although it seems OK). For a bit more (OK a few
thousand....) I could get a full rebuild with high compression pistons etc.
At that stage I'd seriously consider going back to a Rover block due to the
greater availability of parts (water pumps, gaskets, starter motor etc.)
than the Leyland engine, which is a bit of an orphan. There are only three
full gaskets sets available in NZ (through Repco)for the P76 for example. No
new water pumps are available, but they are for the Rover.
All a bit of a long winded explanation, but you can see how I'm thinking. If
I can extend the life of the old P76 engine for another year or two (and it
seems to be in reasonable shape) then I can look at putting aside the money
to get either an RPI Rover V8, or get a decent one built locally.
How is your Daimler/supercharged V6 project going? I'd be very interested to
hear about the progress on that.
Simon
-----Original Message-----
From: Peter Kent [mailto:pkent@skynet.net.au]
Sent: Wednesday, 7 April 1999 11:51
To: Simon Sparrow
Subject: RE: Cam Lobe Wear
Dear Simon,
I have been through a similar exercise with a P76 engine.
If you are going to replace the timing chain, then you have the front
cover off, and probably the radiator out. It is not a lot more work to
remove the inlet manifold to allow replacement of the cam and lifters.
You will not have replaced the cam bearings or recoed the heads, but at
least you will be better of than now, and for a modest investment.
It's an easy job. You remove the lifters, gently slid the old cam out and
after putting lot's of cam lobe on the new cam, do it all in reverse. I
have spent hours measuring the preload on the lifters afterwards, but the
standard set-up is quite tolerant, and if you just tighten the rockers
down to the correct torque, usually the pre-load is fine. The lifters can
accomodate any manufacturing tolerances, if you replace the cam with a
standard grind.
You can, of course, take the opportunity to replace the cam with a "gas
grind". If you want details of what this might be, drop me a line.
Regards
Peter.
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