Part number of the mechanical switch with the large posts??
Cole Hersee 75912-BX
March 11, 2026, 06:51 AM
183N
quote:
Originally posted by Cashflow: Part number of the mechanical switch with the large posts??
Cole Hersee 75910. Have one on both cars. Edit: it’s the 75912.
Moroso rebadges them as a 74108.This message has been edited. Last edited by: 183N,
March 12, 2026, 01:35 PM
FootbrakeJim
quote:
Originally posted by DragRaceResults: For those of you using the Cole Hersee mechanical switch with the 2 small poles for the alternator shut off you need to do your research.
I've posted this many of times over the years, but these are not designed to run the alternator charge wire though as they only flow 20 amps. You may think it's working, but not properly and not charging the way you think it is.
They are designed to control a relay which is used for the disconnect.
Look at replacing or upgrading to the new LARGE 4 POST design and run the alternator though the 2nd set.
SL...
Thank you, Scott. And MarkeMark + 183N for sharing the correct CH P/N 75912 for the switch with 4 large terminals. I fired up my car to move it into the shop, popped the trunk lid to check the voltages at the battery and the master cut-off switch terminals, and the smaller switch terminal that the 10 Gauge Alternator charge wire goes to was actually very hot to the touch. Ordering the 75912 today.
Dan "Jim" Moore Much too young to feel this damn old!!
March 12, 2026, 01:52 PM
markemark
quote:
I fired up my car to move it into the shop, popped the trunk lid to check the voltages at the battery and the master cut-off switch terminals, and the smaller switch terminal that the 10 Gauge Alternator charge wire goes to was actually very hot to the touch.
Consider increasing the size of the alternator wire based on this chart.
March 12, 2026, 02:18 PM
Big Steve
I use the large 4 post with #4 wire from the alternator thru the shut off to the battery
March 12, 2026, 02:23 PM
CURTIS REED
quote:
Originally posted by markemark:
quote:
I fired up my car to move it into the shop, popped the trunk lid to check the voltages at the battery and the master cut-off switch terminals, and the smaller switch terminal that the 10 Gauge Alternator charge wire goes to was actually very hot to the touch.
Consider increasing the size of the alternator wire based on this chart.
The contacts on the small pole will still be the restriction no matter the size of the wire. Unless you are talking about changing the wire size after changing to a larger DPST main switch.
