>jim barbuscia wrote:
>>
>> I have a question (IHAQ) .
>> What is the best way to do a compression test?
>
>
>One important step in the compression testing that is not being
>mentioned by list members is to hold the throttle WIDE OPEN so full gulp
>of air can be sucked into the cylinder being tested.
>
>I always pull all plugs so engine will rotate with the starter at the
>highest possible speed. I have never heard of only removing one plug at
>a time. Could be in an authoritative book somewhere, though.
>
There is a very good and important reason to remove all spark plugs from
the Engine being tested. If all the plugs are left in, with the exception
of the cylinder being tested, and there is a leaky head gasket between
two cylinders this leak may not show up, as they will both build preasure.
Also, most schools of thought indicate that the motor should be turned
with the starter for at least three compression strokes, or more than
six revolutions of the motor. I personally use about thirteen revolutions
to get six compression strokes. The revs are reasonably easy to count
by ear.
Good catch on the throttle being wide open. I normally tie rap the
throttle linkage wide open for a comp test.
So Long,
Darrell Leach, KD6LRC DM-15, Ridgecrest, Ca
email: Triumph_TR4@ridgecrest.ca.us
http://www.ridgenet.net/~token/PAGE1.html
1962 TR-4 (CT5368LO) Every Day
1962 TR-4 (CT13108L)
1965 Spitfire Mk.II
1967 Spitfire Mk.III (In work, lots of 1500 stuff)
Keeper of the TR-4 List. Version 1.4 availible.
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