Morris Minor Owners Club

Hi all,


I have developed a dreadful squeal from my engine. When i turn the engine with the starting handle i get really high pitched squeal, similar to a steam engines whistle...just more high pitched.

I turned the engine on and it is unbearable.

I turned it over with the rocker cover off and it seems to be when one of the rockers over the valves goes down it squeals?

Any advice greatly appreciated!

One very-at-a-loss-youngowner

Fan belt correctly adjusted?

As above -take the fan belt off to check if that's the cause. But I doubt it - if it happens with the handle ! Can we have a bit more 'history' on this please? Was it running fine yesterday - and today there is a 'squeal? Or has it being lying for a while - and only now you are turning it over?

Almost certainly fan belt or extreme lack of lubrication on pulley bearings.

Is anyone missing their cat?

Or possibly the water pump bearings have gone I suppose.. But much more likely to be the fan belt - especially if it increases with revs/engine start

Waiting to hear news of a trial with NO fan belt..........

bmcecosse wrote:Waiting to hear news of a trial with NO fan belt..........

OP has said on MMOCYM that he's now tried with the fanbelt off - unfortunately the noise is still persisting! We've bugged him to film / video it.

Dreadful news to report.... I got a friend to crank the car over whilst i checked again for anything obvious...when he did there was some water being push out of the back of the cylinder head, where it meets the block. A friend had helped me change the HG a while ago and had left me to finish once the head was on. I DIDN'T RE-TORQUE IT... Completely forgot about this crucial step!

Alas it's al experience!

Off with it's head - and fit a new gasket (smear grease on both sides) and refit torquing to 44 ft lbf - and retorque after the first heat cycle. It's only a 1 hour job. And you will need to change the oil.....

Mr.BMC I took the head off and have cleaned it all up however there appears to be black grime like you'd find on a very rich plug on top of the pistons....I thought it was just 'cos it has been running rich but my mate thinks i should consult you!

It's normal carbon, the smoke deposits and stuff that builds up over time from the burning process.

Decoke everything whilst you have the head off and you will see better performance.

fit a new gasket (smear grease on both sides)

Grease if it's a copper gasket, but not for any of the composite types, they should be fitted 'dry'.

A bit of soot will just wipe off with some rag, get rid of the more solid stuff if there is any.
I wouldn't grease a composite gasket either.

Don't touch the pistons - leave well alone. And I would only ever use a copper gasket - not a cardboard one...... Do grind the valves in to make sure the seats are good.

It used to be the done thing to leave a few mm of carbon around the circumference of each piston when decoking as a sort of oil control, especially on engines with a few miles on them. I expect that is old hat now though!

Okay thanks guys, how would one de-coke? I shall use a little grease for the gasket, i take both sides? Also does it need to be of a certain kind or just general grease, like the stuff i use on the nipples - oor matron!

Scrape the crap out of the combustion chambers - then draw the valves and clean them in an electric drill - scrape away any crap in the valve throats - and then grind in the valves !! Don't touch the pistons..........

Multi-purpose grease is fine, on both sides, BUT use on copper gaskets only!

Thin wipe only - but everything must be spotless before assembly - and tighten the studs into the block first........