Bob........
Did you gap the rings? If the end gaps are too small, the rings will bind
when they heat up.
What were the bearing clearances when you Plasti-gaged them? (I assume you
did?)
Did you have the block boiled out and properly de-scaled (shot-peening is
the favored method)? Did you make sure the transfer hole behind the rear
core plug in the side water gallery was clear? Did you - as good XPAG engine
builders recommend - duplicate that hole behind the front core plug in the
side gallery?
Are you positive the cam timing is correct? Where is the ignition timing
set? Were the carbs rebuilt and are you sure your needles are suited to the
3/4 cam?
Lotsa questions because there are lotsa possibilities!
Lawrie
British Sportscar Center
-----Original Message-----
From: Bob Peck <bobpeck@mother.com>
To: MG e-mail list <mg-t@autox.team.net>
Date: Friday, June 25, 1999 11:41 PM
Subject: overheating TF
>Just installed my rebuilt XPAG engine and am having problems keeping it
>cool. Engine rebuild included cylinder resleeving, new bearings, new
>3/4 race camshaft, new valves including valve guides and hardened
>seats. Above work was done by a local machine shop and I assembled the
>major parts and installed the engine.
>
>Symptoms: Engine starts and runs fine for first five miles then
>temperature continues to increase until coolant boils (gauge reads 185 C
>but doubt its accuracy as coolant should be good to about 265F. It
>appears to me that the engine is putting out more heat than the cooling
>system can absorb.
>
>The water pump appeared normal on installation.
>
>The radiator was tested and cleaned by a local radiator shop with no
>discrepancies noted.
>
>Thermostat was tested and opened normally. I then cut out the center
>part of the thermostat and reinstalled just the ring. This helped by
>slowing the rate of temperature rise but end result was still the same.
>
>Any ideas on what could be causing this? Could it be from all the new
>parts, the camshaft etc.? I am just driving it short distances until
>this gets resolved. Total miles on the rebuild now is about 65.
>
>Incidentally air temperatures have been in the 90's the last couple
>weeks.
>
>Bob Peck
>
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