Morris Minor Owners Club

hi, just done a compression test, engine hot, all plugs out, throttle fully open, i got readings of three at 125 and one at 130, engine pulls like a train, with plenty of torque, are these figures to low and should i be worrying? i do get a bit of mayenaze in the filler cap, but i only do very short journeys. regards steve

They are quite low but if it is pulling well and not losing/ burning too much oil then personally I wouldn't worry.

They are low - not quite 'desperately low' - but headed that way...... But if it's going well. Be happy!

It's only really an issue if one (or two) are drastically lower than the rest.

It's unlikely to be the headgasket causing your mayonnaise, as it wouldn't leak equally on all cylinders. As you rightly say, it'll be due to short journeys.

thanks for the above comments, only wish i had not bothered doing a test now, but idle hands and a few hours off!! , but as it does not use oil, or water, plugs are nice and clean, + nice clean exaust, think i will leave alone and just monitor it for a while, thanks steve

Any chance that your compression gauge is reading low? Seems a little strange w/everything else in good order.

I really wouldn't bother worrying if the engine runs really well, but: a) did you do the test with the throttle wide open? and b) did you do the test with a nice hot engine, or with it stone cold? Could make a difference.

hi compression tester is new, ( does not mean its accurate though) test was done hot, and throttle wide open, but as i said it goes well so i will just keep an eye on it, i have had the head of recently and stripped the valves out, cleaned, and regrouned them etc, could be i didnt do to good a job there ??

I'm sure you did - have you retorqued the head and set the gaps correctly?