Regulator

[SimonD]

The regulator on my Sev-Marchel alternator (fitted to a 1977 vintage MD7A) does not seem to be regulating. The battery voltage is nearly always close to 15v. It has dropped occasionally to nearer to 13v, so I suspect an intermittent fault. Can't see anything obviously wrong and have checked/tightened connections.

Solutions appear to be:
- buy new regulator : horribly expensive
- fit 'smart' regulator : don't know if this bypasses the existing regulator
- replace alternator with something more up to date

On the last option, I note that the Sterling Power website advises replacing this type of alternator. If this is sound advice, what do I replace it with?

Thoughts/advice (and offers of a new alternator!) gratefully received.

Simon

 

[pvb]

Take the alternator off and take it to an auto-electrics specialist (look in Yellow Pages). It can probably be fixed for very little. Regardless of this, getting a smart regulator would help you maximise your charging efficiency. Adverc is a good make.

 

[VMALLOWS]

Just go to your nearest car breaker. Alternators go for around £5. The physical mounting is the main factor, though you can usually contrive something with some M10 studding and nuts. The concept of 'Marine' alternators is a joke.....on cars they live within a foot or so of the road sprayed with water (and salt) and seem to outlive the majority of vehicles. Get a spare while you're there!

 

[halcyon]

Sorry, you do not have the right idea, it's a boat, so you buy items at 5 times there value, that you probably not not want or need.

Shame on you, the thought of going and buying a alternator that is cheap.

After all our new yacht has done two trans-Atlantics withit's previous owners. Fitted with a 8hp Saab, and a very,very old Hitachi alternator, the feed to it's internal regulator has been cut and feed to a variable resister, allowing the output voltage to be adjusted. The whole system would have cost less than £20 to put together.


Brian

 

[VMALLOWS]

If you lift the ground wire from the regulator and put it thru about 200 ohms variable resistor you can adjust the charge voltage and still keep it regulated.

 

[halcyon]

That may be the system we have.

When we bought the boat it was part way through a refit, and though the Dynostart was fitted the alternator is not, the wire comes of the brush gear, but as yet I have not striped it down to sort the circuit, the resister is behind a door and complete with hydrometer.

At the moment I may fit a new alternator, and build a bright regulator for it, at the monent it's getting the boat in the water thats the priority.


Brian

 

[SimonD]

Thanks for the advice. £5 sounds better than the £300 Volvo alternative!