Battery hooked up backwards. No life! Help!

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wrench 3

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He probably didn't have a good connection. You can test it at home with a set of booster cables. Clamp the ground cable to the starter case (usually one of the mounting flanges), tighten the nut on the battery cable post of the solenoid and clamp the positive cable there. Then use a screw driver to jump the positive clamp to the small right hand terminal. Hang onto the starter good though. It's going to have quite a kick. Mounting it in a bench vice is the best option.
 

jjones0377

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I would like to fix this from happening again. What size circuit breaker should i put in before the starter? 50A or 90A?
 

alldodge

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I would like to fix this from happening again. What size circuit breaker should i put in before the starter? 50A or 90A?

The starter can pull a couple hundred amps, a bit more depending on size and state of battery, starter. A whole lot of stuff can fry before the fuse blows. I would just be more careful. Like most things, once we mess up, it doesn't happen again that way
 

jjones0377

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I guess thats true. Should i just put the breaker between the starter solenoid and the red/purple wire?
 

alldodge

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I guess thats true. Should i just put the breaker between the starter solenoid and the red/purple wire?

The Red/Purple should go up to a 50 amp breaker on the motor. The normal routing is Red from the starter to the 50 amp breaker and then Red/Purple to key switch/slave solenoid and other point. Being a 1988 model it may not be wired this way or has been changed.

The 90 amp fuse (if it was there) on the starter is placed inline with the ALT orange wire
 

jjones0377

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Ok. So no breaker between battery and starter solenoid. And breakers between solenoid (red) and red/purple and breaker between solenoid (orange) and alt
 

alldodge

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Note pic below is newer 4.3, the breaker (item 7) is between the starter and the Red/Purple connection. The Red/Purple connects to the starter slave solenoid (item 8).

The 90 amp fuse (not shown) is place between the Orange wire from the ALT to the starter. This is a fuse so it will react quick, breakers are slower, also its smaller and will mount on the starter post

and yes no breaker between bat and starter 4_3L elect diag.jpg
 

jjones0377

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Gotcha. Will get all this wired this weekend. And try to hopefully find a breaker I'm not seeing tripped
 

jhebert

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...hope..[to] find a breaker...tripped

I suspect that once you find the over-current device that has tripped and is preventing power distribution, your troubles may not be over.

If you have reversed the polarity of the battery connection to an engine with a battery charging circuit, there is a risk that you have destroyed the rectifiers in the charging circuit. To know for certain if this has occurred is difficult, as the risk of this damage varies with the particular circuitry used in the charging circuit. It is typical in automotive-type belt-driven field-excited alternators that the diodes are exposed to this risk when connected to a battery with the polarity reversed.
 

jjones0377

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I just got it all repaired. Fuse :/. Duuuhhhhh. Was on top of engine in the back of the the engine area. Hard to see area. Once I was given the wiring diagrams. That helped 100000%

As for the alternator. I am worried about it as well and may end up buying a new one. Do you think an automotive one will be fine, assuming it fits. Or must I get a marine?
 

roscoe

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I just got it all repaired. Fuse :/. Duuuhhhhh. Was on top of engine in the back of the the engine area. Hard to see area. Once I was given the wiring diagrams. That helped 100000%

As for the alternator. I am worried about it as well and may end up buying a new one. Do you think an automotive one will be fine, assuming it fits. Or must I get a marine?

Thats like asking if bicycle brakes would be ok to use on your car.
Get a marine alternator for safety sake, or your boat may go up in flames.
 

jjones0377

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Ya I wasn't sure. I just can't get one locally. I haven't found anywhere to test the alternator yet. Anyway to test myself?
 

gm280

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Ya I wasn't sure. I just can't get one locally. I haven't found anywhere to test the alternator yet. Anyway to test myself?

You can always run the engine and see if the alternator is putting any voltage out to the battery. And how you do that is by connecting a volt meter at the battery, red meter lead to positive terminal and black to negative terminal. Take a reading on the meter, then start the engine. Take another reading, it should be higher voltage and go even high if you run the RPMs up some. If it does that, the alternator is basically doing what it is supposed to do. There still could be some current issues but if it does output voltage that increases with RPMs, it isn't acting basically good. JMHO
 

wrench 3

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You should get 14.5 volts with a fully charged battery, 13.5 minimum.
If you can find a shop that rebuilds automotive alternators they should be able to rebuild your marine one.
 

jjones0377

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Ok I'm newer to my area. I'll try to find a local shop if I need one. I couldn't get autozone to test it because it was a marine alternator and they couldn't test it because the model number wasn't in their system
 

wrench 3

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If you find some one that repairs them, they shouldn't have any trouble figuring out how to test it.
Moat garages should be able to direct you to the local rebuilder.
 

jjones0377

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I agree. I'll try to run it next weekend on the earmuffs. See what happens. Boat is stored at brothers house 1.5 hours north. Just getting home from workin it this weekend.

I do want to say I appreciate all the help I've gotten thus far! Thanks everyone for the support!
 
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