Finished up dual battery installation, working well.

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SquareRoot

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K20
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Dual batteries for better starting power on a 6 cylinder? Curious what the compression ratio on that beast is...:shrug:
 

pinballlarry1

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mainly for cold weather and just because I could!
Wiper switch is working correctly, wiper motor park switch is always open. New wiper motor on order, will dissect the old one and see what makes it fail.
 
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calredneck

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Kerch
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I have a battery isolater the problem is I have to use jumper cables the way you have hook up your second battery that if a draw happen you wood loose both batteries I have not done it yet but I think a boat battery switch should work off bat 1 both or dat 2 you would still need an isolator to charge bat 2 I think this is the best set up no battery jumpers turn nob it off or bat 1 or bat 2 or bouth
 

Big Ray

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Nice work. I need some adult size cables for my diesel.
 

pinballlarry1

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C10
Engine Size
250 6 cylinder
Got a couple of hours of free time with no rain today, so I finished up the ground wire upsizing on the '81 C10. Overkill I know but I can rest easy now that everything is large, clean and tight. Here is the stock #10 ground wire that went from the radiator support down to the frame under the lower radiator hose. Someone had already butt spliced it previously. Also pictured is the #6 awg jumper I fabricated from parts on hand:
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Did not have any larger heat shrink on hand so had to use black tape. But I did melt solder into the ring terminal connection.

This is the 5/16" stud I added to an existing threaded ground connection by the stock battery. The small wire on the right is the passenger side head light ground, the larger wire in the middle is the stock #10 ground wire that went to the frame, I kept a 6" pigtail on it for future ground needs. The largest wire on the left is the new #6 jumper to the frame:
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Down at the frame, I added a #4 ground strap between the frame and the main battery negative going to the engine block:
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Someone installed a universal flexible lower radiator hose long before me, it has been rubbing on the ground screw head on the frame. I really hate those type of hoses since they cause massive turbulence inside the coolant flow path. I found an original correctly molded lower hose and will install that next spring.
Didn't get a good photo of the drivers side battery tray when I installed it 3 weeks ago, here it is:
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Easy to install, I used 3/8" stainless steel nuts bolts and washers in the existing holes. Just had to reach in thru the square opening to screw on the nuts.
Both batteries removed for the winter, onto the work bench trickle charger they went.
Total cost of all the overkill parts I added, less cost of extra battery, was $175.
 
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