Alternators and Blocking Diodes

[xeitosaphil]

Originally Posted by pvb
Well, if it's one of those, the regulator isn't adjustable. Would Adverc take it back and swap it for one with an adjustable regulator?

Not sure would have to ask them , but I would need to know if the footprint is the same as this one, to see if it will actually fit on the Yanmar2GM20 with no alterations?

Will check out the Prestolight Web site for the code numbers you have supplied and see if they are compatible size wise.

Have checked out code numbers on the web site and found both alternators are quite similar in size to to the one I have, but are not compatible with their mountings. Both are single mount, where mine is sadle mount, also the cut in speed is 1500 rpm which is just over half my cruising rpm.

Thanks for the info on option, but not really a suitable solution.

 

[xeitosaphil]

The voltage will be fine. A little moderate gassing wont hurt, but check the electrolyte levels regularly.

Ive run open cells at higher voltages than that without a problem.

It was only the possible amount of gas build up that worried me with the electrics in the same locker (4xway permanent fused supply junction box ) but I assume the gas generated will only be small amount and is lighter than air so should vent if locker lid left open, or a permanent vent to outside through coaming.

I think this maybe the best way to go now and this may be the cheapest option/time wise, time is going on and I want to start sailing before the summer ends?

Or has it- we did have two sunny days in a row last week and I may have missed it!

Thanks again for every bodies input - Philip

 

[pvb]

...also the cut in speed is 1500 rpm which is just over half my cruising rpm.

The cut-in speed is alternator speed, not engine speed. Because the alternator has a smaller pulley than the crankshaft pulley, it spins 2-3 times faster than engine revs.

 

[xeitosaphil]

The cut-in speed is alternator speed, not engine speed. Because the alternator has a smaller pulley than the crankshaft pulley, it spins 2-3 times faster than engine revs.

Yes your absolutely right of course - I was typing before my brain had time to catch up - Senior moment!

It’s like running Windows 7 with 4 megabytes of RAM !!