2 Alternators to choose from
 

I am putting the boat back together and have an alternator question. I have the original '87 Mondo (?) style and I have a marine Delco 1 wire style. Since I am going to have mine rebuilt, I have options, not sure about the wiring though.
Let me know your thoughts,
Thanks.

The rebuilder should of been able to answer that without hesitation. 1 wire .

at least the oem people made the alts so they both fit same brackets. the 1 wire Delco is simpler. the Motorola is a pretty tough dependable unit though. Motorola has a rep for making good stuff-except for some of their cell phones!!

I never had a problem with the stock unit, and have 1 wire on all the hot rods. Decisions = )

I'll assume the original alternator was a three wire unit. If so, there are two benefits to this alternator. First, the charging system begins charging right at startup, instead of having to rev the engine above 2k-3k rpm to enable the self-exciting circuitry. Second, one of the three wires is a "sensing" wire, which allows you to maintain the regulator voltage setpoint (14.7V, 14.1V, 13.8V, etc) at any point in the boat (maybe the junction block at the helm?). This allows the charging system to compensate for resistance in the wire leading up to the junction block, or wherever you choose to connect the sensing wire. A 1-wire alternator, while a "cleaner" install can only maintain the regulator setpoint at the "B" terminal. If there is any current draw at all, the voltage will be less everywhere in the system. In a boat, it can be a long run between the alternator and the helm, and voltage losses can be significant. A three-wire system is my preference.

Nauti,
That's the explanation I was hoping for, plus I was leaning toward keeping it simple (as in no re wiring). Any more info on that sensor wire? Have I mentioned I hate electrical!
By the way my screen name on Correct Craft Fan is "Nauti87".

Thanks!

CC230 - I find the following website to be a great resource for alternator tech: http://www.madelectrical.com/electri...esensing.shtml

it kinda makes sence.....I have two different alternators on my older fountain.port is a mando,starboard is a delco.the mando makes 14volts,the delco 12.8-13 volts.both keep the batters charged.but the mando always puts out more voltage than the delco.maybe this is why??

That's a cool site Nauti, thanks, learn something new every day on here!
bcfountain, I bet that's why.

I was going through all my parts collecting brackets for paint etc. I found another alternator, it seems to be a newer smaller version of the Mondo but it says Motorola on it. It has wire spades on the back instead of wire coming out like the Mondo. Does this one sense the voltage also?
Would this be a better choice, output wise? Or should I let the rebuild shop choose?

I was given the opportunity to strip out a couple boats a few years ago before they went to the dump but I don't remember this alternator.

Thanks,