Before I ditch the alternator............

clyst

clyst

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........ Is it repairable ? I bought a replacement back a bit as the auto leccy chap said it was b*ggered . It was constantly charging at about 10 to 20 amps through a smart charger . so before I give it to the marina skip is worth hanging onto bearing in mind I'm a master magpie !!
 
clyst said:
........ Is it repairable ? I bought a replacement back a bit as the auto leccy chap said it was b*ggered . It was constantly charging at about 10 to 20 amps through a smart charger . so before I give it to the marina skip is worth hanging onto bearing in mind I'm a master magpie !!
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My first thoughts would be that it might be the smart charger that is defective, but what exactly is that?

If its a battery sensed system check the sensing connection.

If possible Id try it without any smart stuff

If it overcharges on its own it it most likely a defective regulator. Easily replaced and often a simple DIY job

A decent auto-electrician will be able to test it and repair it .

All the bits of an alternator are replaceable
 
Hi, I had mine looked at, was low output. the shop fitted a new regulator for £35. now working good as new. might be worth having it checked. cheers Smudge.
 
I agree with VicS there is not likely to be much wrong with the alternator that can not be replaced. However it is often difficult to find a replacement alternator with exactly the same mounting and pulley. Hence hang on to the old one.
If your auto lecky chap said it was b***gered without further detail then he either wanted to sell you a new one or simply had no idea what was wrong with it. It sounds like the replacement worked OK so alternator is faulty.
Common failings of alternators are the slip rings and brushes. These carry a small current (1 amp) but do wear out. You can see that the slip rings are burnt black caused by brushes too short or not enough pressure so arcing occurs. Replace brushes and clean slip rings. if the rings are really damaged then you need a new rotor. Easily replaced but then might justify a new alternator.
Failure of a diode. There should be 6 or even 9 diodes in the housing area.They can be tested with a meter or better a lamp and battery. They are cheap and can be replaced.
Finally bearings can wear out which will be obvious with slop and noise but not necessarily causing electrical failure.
As said either just store it or get it fixed by an auto lecky for future. good luck olewill
 
I had a Lucas alternator in one car which at different times needed

new brushes .. fortunately in stock in the local car accessory shop

A new rectifier ... by chance I had one

A new regulator .. the motoring section at work had an account with a local Lucas agent so ordered first thing and in my possession by lunch time

New slip ring assembly .. obtained in the same way as the regulator
 
Get it fixed by an autoelectric shop. Far cheaper than a new one - especially if you were going to buy a spare part for your marine engine which will be a bog standard alternator painted a different colour and doubled in price! And when you are getting it fixed ask them for the part number of a replacement alternator so if it ever does really die (although I can't imagine how that could happen apart from physical damage) you can get a replacement at car spare prices rather than marine engine spare part prices.
 
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