Morris Minor Owners Club

Bad earthing can create a multitude of issues. I have unbolted mine, where they connect to the body work, in the past and scrubbed them with emory/sand paper to bare metal again. The cable from the battery terminal may just need the same. Just remember to put a smear of grease over it to protect it again afterwards. Even if it doesn't turn out to be this, it is good practice.

It might be an idea if you can borrow or buy a voltmeter they are not expensive and you will probably get a lot of use out of it for electrical fault finding. A good 12v battery should actually read about 13.8 volts fully charged. If it won't hold more than 11/11.5 volts it has pretty much had it.

The changeover to negative earth if your car is still positive earth is not difficult (it is available on this forum)but as others have said best sort out the problem you have first.

You need to check the earth strap from the engine to the body. Normally found on one of the front engine turrets spanning the (rubber) engine mounting.
If this is absent or not making good contact the next available path to earth is the choke cable which isn't designed or up to carry this amount of electrickery.

I agree -these lads have put their finger on the real problem - bad earth. It will weld the choke and/or throttle cable to the outers! This is a reasonably common problem on Minis - the cables have been seen glowing bright red. Less common on Minors - I guess because the earth cable at the gearbox is more secure, + high likelihood of an earth path through the prop shaft to rear axle and hence to the body. But it certainly IS very much a possiblity.

high likelihood of an earth path through the prop shaft to rear axle and hence to the body

If the rear bushes have worn away and the springs are rubbing on the pins?
I doubt the brake pipes will offer much of a return path either.

Thanks everyone!

The cables all look good - the earth lead is solid and the battery wouldn't recharge overnight, so i'm sticking a new battery in and keeping my fingers crossed!!

I think bearing in mind it started straight away on a jump and sounded right, and the lights took a while to brighten up whilst the engine and battery were running together that battery is the first problem - if she doesn't play then i'll have another look.

Any chance you have been reverse charging the battery ? ie - It has been connected wrong way round - and run flat - and the dynamo has forced a 'reverse' charge into it - which will ruin it !

all sorted - apparently just the battery. these new batteries are very small though aren't they?

My possibly final question for now - i have a rattle in low revs across the gears - sounds like it comes somewhere around the front of the passenger side - have run her on low revs with the bonnet up - nothing looks loose or vibrates / is catching. It could just be the loose passenger shelf i guess - but anything i should be looking for?

You need to decide if it's an engine (or gearbox) rattle - or a car rattle. ie - does it only do it with engine running - or is it there is you drift down hill with the engine off ? Sure it's not 'pinking' - when you accelerate away ?

tends to quieten off when accelerating, but come back when slowing down and at low revs.

Some of it may be car noise, like a door rattling (maybe linked to that locked door) but some sounds as if it is coming from directly in front of the heater. It doesn't do it when sitting in neutral, which makes me worry that it could be the gearbox - there is some difficulty in hitting first on occassion but i've always assumed that's my new driver inability!

markthe45king wrote: there is some difficulty in hitting first on occassion but i've always assumed that's my new driver inability!

There is no sychro on 1st gear so you either have to be stopped or double declutch to get a smooth change on the move - but you knew that?

I think the rattle will be difficult to diagnose by description only. Go round the car and check all nuts and bolts are tight. Rattle things about and see if they move. Check the parcel shelf is secure. Check the window rubbers and seals (esp door glass) and finally check there is oil in the engine and the gearbox. Once yiu are sure everything is tight (or removed) we'll go from there.....

yeah i know about 1st, sometimes she grinds static.

The parcel shelf is loose and there are 2 old ashtrays connected underneath that rattle a bit, but the noise sounds "bigger" than that. but i will do the rattling!!

clutch sticking perhaps

If the rattle can be traced to the doors there is a metal bar that operates the lock. This can rattle really badly. It's easy to fix with a bit of felt or foam to keep it away from the door skin. Originally there was a felt sleeve fitted but they rot and fall off.