volvo penta alternator

[Freebee]

One of my VP alternator is on its way out, it will be expensive to replace, can I replace with a car or commercial vehicle one? And if I replace with an auto one does it matter which direction an alternator turns, if its been made to turn clockwise and I turn in anticlock will it still perform?

 

[john_morris_uk]

Electrically its doesn't matter. However, the fans of some alternators are designed to cool them properly in one direction of rotation only. Check that the cooling is ok - if it is there is no problem.

Remember that an alternator is only rated at maximum out put when it is cool/cold - it will have a lower output as it gets hot!

 

[Sixpence]

why not have it rewound , most industrial estates will have a motor rewinder , don't see there would be any difference and would be a lot cheaper

 

[halcyon]

Most alternators run one direction, if they are on the right or left of the engine, they will rotate in the same direction as crank shaft.
In the old days alternators were rated in WATTS at a set voltage, 14.0 volt from memory, into a resistive load. That was for supplying electric loads on cars, ie heated rear screen, lights, air con etc. Your battery is not a resistive load, so the output from the alternator will vary from stated. Added to this you are supplying resistive loads at the same time, ie lights, nav eqiup, fridge etc, so this will also alter your amps that you see.


Brian

 

[VicS]

What is wrong with it? Trevera25 assumes that is the windings that are burnt out but I reckon that is the least likely thing. More likely things are brushes, the diode assemby or the regulator. The brushes are usually easy to replace the diode assemby (rectifier) and the regulator may also be just as easy. Some modern alternators have a combined regulator and bush assembly.

I also once had to replace the slip rings on a Lucas ACR. That required a bit of soldering and needed a largeish soldering iron.

Some older VP alternators did not have brushes (or slip rings).

A good local Auto electrician will be able to identify the fault and repair it for you.

 

[halcyon]

Vic in the 80's I had a firm producing exchange alternators, the ones we had back in,

40% had worn out brushes,

30% faulty rectifier diodes

20% faulty controllers

10% faulty windings, bearings or broken brackets

%'s are approx as it was 20 odd year ago now, but they were in that sort of order.

Brian

 

[charles_reed]

Don\'t

even think of buying a Volvo spare, unless your pockets are bottomless.

You could replace with a commercial aftermarket alternator and that would be cheaper but probably have a shorter life.

Marine alternators usually are double insulated and have ss bearings.

Try Adverc - they supply replacement Lucas marine alternators for about £125 for the 90 amp version. Tel 01902 380494.

 

[alldownwind]

I would take it to an auto-electrician as others have suggested. Chances are there's little wrong with it - the last time I had one spruced up it cost me 50 quid.

 

[Sixpence]

totally agree with the others , daft of me to assume the other parts had already been checked , so no argument , especially halcyon percentages , look at these first but don't give up and throw away

 

[Kurrawong_Kid]

Look at the part number and ask Volvo for the present equivalent part no. if applicable. Then go to ebay and see if anyone is selling one that matches your needs. You might get one for just a few quid!

 

[William_H]

The concept of alternator on the way out is a bit absurd. They fail or they work with one small exception of some diodes failed. Anyway take the brush holder out and look at the slip rings. They can be cleaned up with abrasive paper unless they are really worn and brushes can be replaced if you think they are short. In any case a repair is the way to go. I feel sure you will find the alternator is just a commercial one with VP label and cheap spares will be easily found. olewill

 

[Solitaire]

This maybe your lucky day! When I replaced petrol with diesel, I kept a load of bits! One such bit was the alternator. It's in my garage - I think - If you are interested let me know and I'll dig it out.

 

[halcyon]

The concept of an alternator on the way out, was quite common when we were doing alternator rebuilds. Sticking brushes that were intermitently touching, or worn brushes that were just kissing the slip ring, we had out of round or teue slip rings. Probably the major failure in all the returned units we had than. I did have one alternator that worked when it was hot, but shorted out the windings when cold and flatened the battery over night.

Brian

 

[martin99]

I have 2 of these Prestolite on order from my Gillingham motor factors Superior quality vehicle components in Rochester, they are marine ones.
Prestolite Electric & Leece-Neville Alternators – Industry-Best Output is a 70amp one £100+UK vat 20pc. Will use existing pullies I think.
When I get a part number can advise others. I also have a problem with the D+ volts on one engine as I get no ignition warning light when ign on but stationary. I will check to see if any stator 'exciter' volts are appearing with ign on when next at boat. Parts on 2 week+ back order.

 

[westernman]

If you need a new one, Balmar do some decent ones.

 

[Wing Mark]

I would take it to an auto-electrician as others have suggested. Chances are there's little wrong with it - the last time I had one spruced up it cost me 50 quid.

The last time I bought one from a breaker's yard, it cost me £15.
I had to have one fitted to a car by a garage, because you need a a hoist to access, pretty sure it only needed £4 worth of brushes, but a new alternator cost me £150 fitted.
I have a friend whose company does motor rewinds, it's often not economic to rewind car alternators. The coils are pretty robust, if you cook them, then the diodes have probably not enjoyed the experience and may fail shortly after.