marine or auto altenator?

[bcasurvey]

1. can anyone tell by looking, if i have a marine or auto altenator on this boat???

2. if the excitation lead and sensing lead were hooked up backwards would it cause my ignition to not shut off??? (i've check ignition switch and wiring somehow the altenator is suppling 12 volts to the coil with the key off)...

 

[tpenfield]

Re: marine or auto altenator?

I had that same question a while back. As I recall there was no good way to tell just by looking at it. If you can get some ID numbers off of it, then you could possibly find out. If you find a label that says "SAE J1171 Marine, you are all set.

It may be worth replacing with a known marine alternator if you cannot verify.

 

[mark1905]

Re: marine or auto altenator?

View attachment 140386View attachment 140387View attachment 140388
2. if the excitation lead and sensing lead were hooked up backwards would it cause my ignition to not shut off??? (i've check ignition switch and wiring somehow the altenator is suppling 12 volts to the coil with the key off)...

There is absolutely no way that the alternator is supplying voltage when not spinning. It's the battery being hooked up to the alternator that's supplying voltage when the key is turned off.. and if your coil is getting power even when the power is turned off, then you have a mis-connected wire somewhere.

 

[sjohnson44]

Re: marine or auto altenator?

Idk if your asking if your alt is an auto or marine, but that looks just like the one a guy at Advanced Auto tried to sell me in place of my marine one.

A lot of farmers and such had the alts with the excitation and sensing leads and the ground and power. The alt you have didnt come fashioned that way and if it were to be replacing the OEM alt, would need some rigging.

If you are wanting to replace and need the leads and such on the alt, check on ebay. A lot cheaper and marine.

 

[Eric 3.7LX Alpha 1]

Re: marine or auto altenator?

The alternator has an internal diode which prevents backfeed when switched off. Yours may be damaged.

a diode (not a resistor), could be added externally, connect it so that the current will only flow from the ignition terminal of the ignition switch to the alternator. A diode only allows the flow of current in one direction. The diode will prevent current from going back to the ignition switch and this will prevent a "run on" condition when the ignition switch is turned off. Use a Radio Shack #1N4001 diode or an equivalent value

OR

Either rebuild or replace your alternator.

 

[bcasurvey]

Re: marine or auto altenator?

i meant to say with the engine running.
when i turn the key off the engine keeps running

 

[fishrdan]

Re: marine or auto altenator?

I don't see a front screen, or a back screen, so I say it's an an automotive alternator.

 

[bcasurvey]

Re: marine or auto altenator?

thanks eric that may be the answer,
but i still need to verify the wires are hooked up correctly

 

[bcasurvey]

Re: marine or auto altenator?

Idk if your asking if your alt is an auto or marine, but that looks just like the one a guy at Advanced Auto tried to sell me in place of my marine one.

A lot of farmers and such had the alts with the excitation and sensing leads and the ground and power. The alt you have didnt come fashioned that way and if it were to be replacing the OEM alt, would need some rigging.

If you are wanting to replace and need the leads and such on the alt, check on ebay. A lot cheaper and marine.

i was reading that out of the service manual

 

[RogersJetboat454]

Re: marine or auto altenator?

Looks like a standard Delcotron alternator found in millions of GM cars and trucks. The marine version of this alternator usually has prominent screens on the front and back. I would be pulling this, and plan on replacing it.

FYI, if I remember correctly (haven't had one of these apart in years) the little hole you see in picture 3 right above the bearing support is where you place a paper clip or something rigid to hold the brushes back while your putting the alternator together. That little hole ain't too far from arcing brushes.

 

[dan t.]

Re: marine or auto altenator?

Definetly an automotive alternator, no screens, you need a diode or a resistor in the wire from the ignition. The resistor can take the form of a lightbulb, just wire it inline , if you mount it in the dash it workes just like the idiot light in a car,goes out when it is charging. The big advantage is that it will go on if the alternator stops turning when you loose a belt.

 

[bcasurvey]

Re: marine or auto altenator?

update, the diode worked, its an auto alternator. i'm glad its not a short somewhere, i'll buy a marine alt after i get the bugs worked out.
thanks all...