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Old 11-23-2018 | 02:12 PM
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ttrm007
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Default Alternator Fused?
Working out the details on a few big items.

Charging System:
I'm taking a 4awg wire from my alternator (1 wire 105 amp) to positive of battery. Do I need / want this to be fused? Maybe something like this?
Amazon Amazon

Trim and Drive Pumps:
Not sure what gauge wire yet? Probably just go with 4awg again? It his pretty big. Same question on the fuse.

Thanks.
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Old 11-23-2018 | 03:21 PM
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ttrm007
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Originally Posted by ttrm007
Working out the details on a few big items.

Charging System:
I'm taking a 4awg wire from my alternator (1 wire 105 amp) to positive of battery. Do I need / want this to be fused? Maybe something like this? https://www.amazon.com/dp/B015ABMN6C..._t2_B06XW27WMD

Trim and Drive Pumps:
Not sure what gauge wire yet? Probably just go with 4awg again? It his pretty big. Same question on the fuse.

Thanks.
Maybe this is better?
https://www.westmarine.com/buy/blue-...5?recordNum=44
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Old 11-23-2018 | 04:23 PM
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Mercruiser uses this mounted on the starter, and yes you need one. My DB Electric alternator shorted and the starter and ground lugs immediately started to smoke (the previous owner removed the fuse). Had I not been right there the whole boat could’ve been a toasty puddle of burnt ash. It’s barely rated above your 105a unit so it may not be enough.

https://www.boats.net/product/mercur...saAuajEALw_wcB
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Old 11-23-2018 | 04:26 PM
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why are taking the output from the alternator direct to the battery, typically it goes to the starter + terminal where the battery hooks up, OE mercury wiring its orange
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Old 11-23-2018 | 04:52 PM
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On a side note, 105a seems like a lot and requires heavier wires all around. I’m running three batteries with 85a and installing a charging isolator to ease the load a bit.
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Old 11-23-2018 | 11:37 PM
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ttrm007
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Originally Posted by F-2 Speedy
why are taking the output from the alternator direct to the battery, typically it goes to the starter + terminal where the battery hooks up, OE mercury wiring its orange
Ok so alternator to starter. Makes sense for a shorter run. Put fuse right on lug.

Thanks!
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