Need help with wiring questions

Fishermark

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Actually I have two questions:<br /><br />1) Is it possible to buy a complete engine wiring harness for a mid 80s vintage Mercruiser 3 liter engine? If so, where could I find one? (The harness on my dad's boat has been spliced and cobbled together in too many places for my liking :eek: ).<br /><br />If I cannot find one (and reasonably priced :) ) I will probably end up making my own. I would rather not have to "reinvent the wheel" however. :rolleyes: <br /><br />2) Just a question to satisfy my curiosity -- can anyone explain to me the purpose and function of the slave or assist solenoid in the starting circuit? I understand the purpose of solenoids in general - (at least I think I do!) - they are basically big, heavy duty switches which transfer a lot of amps. But what's the slave or assist solenoid do?
 

Bt Doctur

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Re: Need help with wiring questions

my understanding is that the boats wiring is too small to carry the current from the switch to the solenoid by itself,a low current slave is used to trip the main solenoid.
 

Laddies

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Re: Need help with wiring questions

Yes the harnesses are available from mercury, the slave solinoid premits the use of smaller wire in the boat wiring harness
 

WillyBWright

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Re: Need help with wiring questions

A harness should still be available. Except for ignition systems, those haven't change much. If there are any significant differences, it's probably just wire lengths.<br /><br />The slave allows a more reliable start when the wiring harness between the helm and motor gets long. For most trailerable boats it's not a problem and not terribly necessary IMHO.
 

Fishermark

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Re: Need help with wiring questions

I'm not sure I can get a serial number off this engine. I don't even know the exact year of the boat - I believe it is a 1986. I know that date is close. ;) I can find out for sure, but in the meantime, I also know it is a 19' Sportcraft with a 3 liter engine. (At least it came with a 3 liter originally, it is still a straight four, but it is actually the "120" engine now. The block was changed out a few years ago). I have searched around a little, but cannot seem to find a listing of a wiring harness. Any specific places to look?
 

Bondo

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Re: Need help with wiring questions

1) Is it possible to buy a complete engine wiring harness for a mid 80s vintage Mercruiser 3 liter engine? If so, where could I find one?
Email Me......... I Think I can Help you out......Include "Boating" in the subject line......<br /><br /><br />Post after you find this address,+ I'll edit it.....
 

Bondo

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Re: Need help with wiring questions

Ayuh,......................<br /><br />Now Your Phone is Ringing............... ;)
 

Bondo

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Re: Need help with wiring questions

Ayuh,......<br />You'd Think I've Never posted on this forum before............. :D <br /><br />Sorry for the double post...... Got lost with the Back Button.......... ;) <br /><br />It's All in the Post Count,....... Right KaGee..?? :D
 

Bondo

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Re: Need help with wiring questions

Mark,........<br />Be expecting a package Any day now.......... ;)
 

Fishermark

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Re: Need help with wiring questions

Indeed he is! I will be anxiously awaiting the mailman... or UPS driver as the case may be. :D
 
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