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MG MGF Technical - MGF cylinder compression problem

I just replaced head gasket on my MGF. I did all the work except fitting the timing belt and some minor things that the mechanic could do more easily on hoist.

He returned it not working. He said that while he was flushing the coolant the head gasket was leaking under exhaust near number 3, near impossible to see that location. (In fact I have removed manifold and will use small video camera to try to see if there are any stains)

He siad that I didn't bleed the lifters. I don't understand this as if you turn the cam the valves open therefore the lifters bleed.

Can someone please explain what he may have meant by this comment.

I had to tow the car home as I wasn't ready to spend more (small fortune) and the engine turns over but there is no compression. He claimed to have had it running as he said he saw a leak from the head gasket and now it's not running at all.
j osborne

Coolant leakage by cylinder 3 is I think rather unusual, but coolant leak over cylinder 4 pretty common, where the elastomeric beading can peel off and therefore fail. It is possible that the gasket was damaged during reassembly? Did you have any problems at the time?

The lifter comment is a little difficult to figure - perhaps he meant that one of the hydraulic tappets is failing to re-charge?

Is the lack of compression seen on all four cylinders, or just cylinder 3?
Rob Bell

Perhaps his remark about the lifters was due to getting a lot of valve noise when it started - if empty they will take a while to fill, and won't sound good.

To go from 'running' to not showing compression indicates either the valves are not closing fully, or the cam timing has changed. First thing I'd do is check all the timing marks line up. I can't think of any reason the valves wouldn't be closing fully just due to the lifters being low on oil, only if they had over-filled could they prevent full closure.

Was the head checked for flatness, or skimmed? Presume the standproud of the cylinder liners was checked too?
bandit

This thread was discussed on 15/03/2010

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