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RE: The Head is Off

To: "'Austin-Healey List'" <healeys@autox.team.net>
Subject: RE: The Head is Off
From: "Michael Salter" <msalter@precisionsportscar.com>
Date: Sun, 16 Apr 2006 15:54:40 -0400
Hi Ned,
Rebuilding an engine on a budget is tough. The time and consumables
(gaskets, oil and blood) used in the process make cutting corners somewhat
unwise. 
I have always found that upon discovering something in marginal condition I
have been unable to reliably assess just how much the deterioration will
affect the running and performance of the engine if it is reused.
A classic example is rod bearings. You will have to remove at least one rod
cap to pull the damaged piston. When you do you will almost certainly find
that the bearing is worn and probably through to the copper. Of course it
would be foolish at that stage to replace just the one so you will probably
replace the lot.
While you are removing the rod bearings you will invariably look up at the
cam and notice that at least one of the lifters is all pitted and its
associated cam lobe is worn badly; so it is pretty hard to put things back
together knowing that the cam is only going to get worse.
However, since you found the rod bearings is such bad shape, you will think,
"I better take a look at at least one main bearing" and the result will
probably be the same. Of course you can't replace the front or rear main
bearings without taking the crank out and you can't take the crank out with
the engine in the car, (well you can, I've done it at a race track, but it
is one hell of a job) so then you have to decide where to go. 
In my experience patch up engine jobs are seldom satisfactory. You seem to
spend about 50 -70% of the $ that a complete job would cost only to finish
up with an engine which will need to be done again before very long.
In my experience the least expensive job in the long run is to disassemble
and reassemble the engine yourself and send all the machining work to a
reliable machine shop. 
If you have never rebuilt an engine before rebuilding a 6 cyl Healey engine
correctly requires a lot of careful work. Anyone can put one together which
leaks oil and rattles.
Of course you could just pop out the piston(s) which have obviously broken
rings, put in some used pistons with new rings and go on your way, but I'll
bet you don't get too far.

Michael Salter
www.precisionsportscar.com
 

-----Original Message-----
From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net] On
Behalf Of Ned Smith
Sent: Sunday, April 16, 2006 2:22 PM
To: Austin-Healey List
Subject: The Head is Off

The water temp. sensor finally released and the head is off. Those of you
that suggested Broken Piston Rings were correct. You will receive your
checks by certified mail shortly. I found a < piece of ring laying on top
and small opening at the edge of the piston.  You can see a rub mark in
the cylinder wall but I cant feel any scratches with my thumb nail. I hope
this means I wont have to pull the block and re-bore the cylinders?



This project is being done on a budget so I want to do everything that needs
to be done and nothing that doesnt.

I know that that piston and rings must be replaced. Should all rings be
replaced?

How about replacing all bearings I can reach?

Should I rebuilt the oil pump?

Should the valve seats be replaced and the valves ground?

I have already sent the rocker assembly out to be rebuilt.





Any suggestions will be greatly appreciated,



Ned Smith

BJ8

near Chattanooga, TN

N34.98 W85.5




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