Alternator for 2001 Searay 21' BR

[SearayBR21]

I think I have a bad alternator. I've done the voltage checks and I get 12.8 with engine at idle and 12.4 with engine above 1500. Yes, lower with engine at higher RPM...strange. In any case, I'm looking at alternators and I can get one from the dealer for $300 or so but I found this on Amazon and eBay for $69....big difference and it seems to be identical to the unit I need...any comments or opinions on whether the cheap alternative is worth a risk. Here's the link to eBay. https://www.ebay.com/itm/New-Altern...1-SAEJ1171-Certified-for-Marine-/282910828901.

Any response would be appreciated on the alternator and also any idea why the alternator is putting out less voltage at higher RPM would be appreciated.

Thanks!

SearayBR21

 

[scoflaw]

I'd give it a shot at that price. Does the back of it look like yours?

 

[SearayBR21]

Yes, the back looks identical. The only thing that concerns me (BTW I did order it from Amazon) is that I've heard that if the alternator is not built marine grade, it could create electrical sparks and lead to explosions....for example, an automotive alternator installed in a boat could cause sparks leading to explosions... What are your thoughts on this?

 

[SearayBR21]

They call this "spark protection" I think...is this just myth or fact?

 

[scoflaw]

That 1 you linked to is spark protected

 

[SearayBR21]

Fantastic!! that makes me feel a LOT better! Thanks very much. I'll report back if the new alternator solved my problem or not.

 

[Lazy Daze]

The only thing that makes me wonder is that is an AWFULLY low price and I don't know if I'd trust that the spark protection is actually done correctly. I think it'd be something that I would always be worried about. You don't need to buy the Merc brand - although they are fully painted to help ward off corrosion and rust... but that, in and of itself, is certainly not worth the premium, of course.

 

[SearayBR21]

Lazy Daze - that was my initial thought and now I'm worried about that again. It's either $70 or $250 and up....is "spark protection" an expensive or technically hard thing to create or is it merely a screen/mesh that prevents sparks...Any way to ask the vendor/seller do you think?

 

[SearayBR21]

at the end of the day, a couple hundred bucks is good insurance to avoid an explosion!!

 

[scoflaw]

Your linked alternator has the marine rating. Yes, it's a screen preventing the spark. How much extra do you think a piece of screen is? I would'nt sweat it, but your call

 

[SearayBR21]

Thanks Scoflaw - I definitely value your point of view. Is there any way to visually check the screen or check for proper spark arrestment? I agree with you the screen can't be a difficult thing to integrate....