Can it be anything other than Alternator?

[Mcalvert]

Last night I drove home through a blizzard with the car having sat outside at work all day.

 

As I set off, I realised something wasn;t right as the ignition light was glowing intermittently. Most of the way home it went out, but came back from time to time. After about 20 miles the car started misfiring, the lights got dimmer and she finally stopped about 500yds friom home

 

A jump start, and everything came up normal however, fully bright lights, no misfire etc.

 

My thoughts are that the alternator must be duff, but putting a multimeter across the battery when the engine was running shows a heathky 14.something Volts depending on revs. Is there anything else that could cause these symptoms or is it possible that this is an intermittent fault?

 

Thanks - Michael.

[Kevsta]

My old mini cooper did the same things if there was a lot of rain, think it is water ingress in the alternator.

 

Kev

[Graham Sewell]

dirty battery terminals, loose earth strap, knackered battery master switch would be the first three things that I would look at.

 

Then the connectors on the back of the alternator have been known to become loose so a slight crimping up may be in order.

 

Low tech luddite - xflow and proud!

[Normans_Ghost]

Second Graham. I had a nightmare tracking down the loose alternator wires many years ago. The heat tempers the the large lucar connectors and, whilst they look ok they are, in fact, not making contact at all or have a high voltage loss. Pull off (if faulty they will "fall" off) and replace with new or at least pinch together with pliers.

 

For long term fix fit new ones and cover with a strip of cool tape.

 

Better still invest in Brize unit with screw on connectors.

 

Norman Verona, 1989 BDR 220bhp, Mem No 2166, the full story here

[Felix E]

McAlvert,, sounds exactly like what I had post-build. The problem was an almost impossible to find issue (well done CC) which was the earth strap from the alternator being broken internally, so the fault was both hidden and intermittent. Caterham had a batch of these all with the same problem. Something to check if all else fails.

 

Best Regards, Felix.

 

 

[Tim_H]

Michael,

 

Do you work Burnt Mills way? - Green with yellow nose?

Tim

[Coose]

Loose fan belt. It may not seem it, but it could easily be! I fitted a brand new Mintex belt to Soozys '66 Mini and had no end of charging problems. I would be tightening the belt at least once a week, and she doesn't do that many miles! Then I replaced it with a new Ferodo belt and it seems sorted!

 

We will mend it We will fix it...

[owelly]

In a blizzard you say? (That shouldn't have been a question really 'cos I re-read your post so I know it's what you said).

If your electrolyte in your battery is on its way out, the watery wetness starts to seperate from the acidy bit and freezes. I had many bemusing trips in a car that would do what you say just after I had set off when it was freezy cold. By the time I had sat to wait for a jump 😳 the battery would hold enough charge to go a bit further. If the weather was ok it never gave any bother. Wrapping a cardigan around it helped until I saved up for a new battery. A fleecy top would have had a similar effect.

 

its only a game.........

[D289 SGT]

I had something similar but without the blizzard. Some days the red light was glowing, somedays bright and some days out. Eventually the alternator packed in altogether with a broken diode.

Alternator removal revealed that the wiring to it was very taught and the connectors were only just hanging on.

This was because the metal/rubber engine mounts had become unbonded and the engine had shifted over to the right, pullling the wires off the alt. This also explained why it was getting difficult to take the bonnet off and over the carbs/filters.

Sort of a chain reaction.

 

Nigel

 

 

'86 Cat 7 1700 Super Sprint