Morris Minor Owners Club

hello chaps

The other day I started the van after a couple of days of not running it, and it sounded like a lawnmower When I put it away after previously using it it was running fine.

It's sounding like a lawnmower when it's under any acceleration or load at all - but it sounds normal when it's coasting or going downhill.

It sometimes bunny-hops very slightly.

There's a bit of vibration coming through the gearstick and the pedals.

Compression test shows even compression on all four cylinders, but rather low at 100 (no 3 was 110). All plugs sooty around the edge with a burnt, biscuit-coloured central portion - except no 2 which was wet and not sooty.

I haven't played with the carb yet - except to check that the piston isn't sticking.

I'm less well than usual with the ME, and horribly busy (my parents are selling the property so I am tidying and clearing stuff out and cleaning the place), so I thought I would post here to see if the symptoms can give someone a clue as to what the problem is - rather than me having to try everything in turn (thus spake the novice... )

help!

wibble

its not a blowing exhaust is it? Or tappet adjustment?

Points, plugs, dizzy cap, rotor or leads.

Try another plug (and wire) if you have one in number 2.
You can pull the plug caps off while the engine is running and see which one makes no difference to the tick over (that one will be the non firing cylinder)
Use thick gloves and keep the end of the plug wire close to the block and as far as possible from your hand.
You can get shocks doing this so educational for kids an apprentices.
It does isolate non firing cylinders very well though.

Watching the engine run in the dark will reveal any sparks going astray.

Sounds like number 2 is misfiring. I'm pretty sure the carb will still be OK. Have you tried scraping the contacts in the distributor cap clean?

These compressions are all horribly low. And the #2 plug report is not encouraging. Maybe it's just oiled up - worth trying another plug and hope for the best! If it does then run alright - take it for a decent run right away - then check the compressions again on return.
Long term (but not too long) - you should make plans for an engine swap.

Thanks very much, everyone

BMC - an engine swap is already on the cards - but I need to get to Cumbria and back first Yes they are very low compression results. I felt encouraged to find that they were even, though. I cleaned all the plugs just last week (they get sooted up as the engine is burning oil from somewhere - or running very rich - something which no one so far has been able to cure, thus {partly} the engine swap).

Alex - yes I've cleaned the contacts, just last week

MarkyB - thanks very much for the tip, I will try that tomorrow

Peetee - thanks, mate - I will try and work through that list.

Matt - I dunno! come round and mend it! I must have done the effing tappets three or four times since November and I have the scars to prove it

I only tend to hurt myself fixing other peoples cars.... good cut from doing Dans tappets last week!

I cut myself every single time I do them

Ju - do you by any chance have the proper LCV low compression engine in the van? If so, then 100 is not too much to stress about.
If not, then it's mildly alarming but at least all are similar.

Oiling up a plug may well be down to a poor spark, however it can also be down to poor oil rings / damaged bore. Servicing the lectrics and changing that plug may help but if it's only temporarily better, then the engine is on borrowed time.

Even on the Low Comp engine - 100/110 is pretty desperate!

However - to get the best possible result - you need hot engine with fully charged battery. Remove all the spark plugs, and prop the throttle open slightly (to let air in) - then test each bore in turn, letting the starter run for about 5 seconds on each bore to get steady best reading.

Thanks Ray How would I tell whether I had the LCV engine in, or just the standard 1098? (I've gone past stressing, and out the other side )

rayofleamington wrote:Oiling up a plug may well be down to a poor spark, however it can also be down to poor oil rings / damaged bore. Servicing the lectrics and changing that plug may help but if it's only temporarily better, then the engine is on borrowed time.

I suspect the oil rings, thus the projected engine swap Thanks very much for the tips xxxxxx

wibble_puppy wrote:Thanks Ray How would I tell whether I had the LCV engine in, or just the standard 1098?

I think the engine number will start with something like 10M/U/L (low) vs 10M/U/H (high).

I suspect the oil rings, thus the projected engine swap

Not to mention the gradually failing oil pressure...

alex_holden wrote:

wibble_puppy wrote:Thanks Ray How would I tell whether I had the LCV engine in, or just the standard 1098?

I think the engine number will start with something like 10M/U/L (low) vs 10M/U/H (high).

Cheers for that

Not to mention the gradually failing oil pressure...

Seems to have stabilised at the moment *touches wood*

Well, it was a faulty spark plug. Purring again now (and so is the engine )

Thanks for all your help, everyone!!

I once rebuilt a saloon engine to go in an LCV (with the heavily dished pistons), and there'll be a fair few low comp LCV engines that now have standard pistons - however the engine number is normally correct regarding high and low comp.
The only 100% sure way to tell is by taking the head off and looking at the pistons.

Glad to hear a plug sorted the problem - for now. Best carry a few spares with you - it's likely to happen again if burning a bit of oil. May be worth going to a 'soft' plug like N12Y until the engine is swapped - less likely to 'oil up'.

Well, it was a faulty spark plug

Ah, smug mode.

wibble_puppy wrote: Purring again now (and so is the engine )

Wibble, we all know it's kittens that purr not puppies!

Glad you found the problem, if I were you (which would be funny) I'd put a spare sparkplug in my tool kit just in case.

Here is one of our puppies purring through his daily weigh in.

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And here again a few weeks older.

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Sorry about going off topic!!!

lol @ peetee

Yeah, i carry spare plugs - as well as every other conceivable spare and tool from jubilee clips to starter motor Sod's law will dictate though that any time I break down it will be for want of something I don't have with me - eg recently the wiper motor burned out

It was quite funny at the garage I was at yesterday having the tracking checked (after fitting polybushes to the front suspension) - every time they reached for a tool I was there before them with one of my own tools out of the kit I carry

Incidentally, very interesting having the tracking checked - I was allowed to "help" and it was most instructional