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MG MGB Technical - What should the compression reading be?

I'm over from the TD/TF board. What should the compression reading for each cylinder be for a 68-MGB? Thanks John
John Hambleton

Low compression 140 lb and high compression 165lb.
Denis
Denis4

Thanks Denis
I was told they read 100, 120, 120 and 110. It's on a 1968 MGB-GT? I have a work shop manual for a TD but not MGB. Is this good or bad. Thanks in advance, John
John Hambleton

About time for a valve grind and check the cylinders for wear. Only the cost of a head gasket if you do it yourself and find nothing wrong!
Mike
Mike Ellsmore

They are all in the same ball park, so if the engine runs OK it can probably be left until it's convenient to strip it down. Doesn't the US spec MGB have a lower compression engine than ours?
Mike Howlett

My B was imported from the states and is a low compression engine. Thee last time I check the pressures they were approx 125psi.
john wright

The compression test must be done on a hot engine, all plugs out, throttle wedged wide open, or you will get low readings.

North America got low-compression engines from the Mk2 onwards.
paulh4

This thread was discussed between 14/02/2017 and 15/02/2017

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