Engine bay grounds

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New_Guy

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I'm going through my first rodeo of doing an engine/ trans swap on my 85 C10. I'm getting ready to hook up my a/c, main battery and cab to motor ground, the only catch is my new manifold, heads, and water pump are aluminum. So rookie question in bound.
The battery ground that grounded to the lower alternator bracket is now bolted through aluminum as well as the a/c ground, and the cab to engine strap would go into the aluminum as well. I have been told this is a huge no no becauseos some sort of corrsion because of the current passing through two different metals. Before I spend a decent amount of time and energy making longer ground straps to go to the very limited holes on the cast iron block. Can I ground to the new aluminum parts?
I'm not running anything fancy for an ignition system, Im just running a stock style hei distribor too if that matters.
Thank you for the help!
 

DoubleDingo

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And never enough grounds. Think you have enough, add one or two more. You want a good clean path back to battery negative through all of the core support, frame, engine block, bed, fenders, cab, etc.
 

Scott91370

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The elctrical system encompasses copper, steel and lead already. And your aluminum heads already have steel bolts/nuts attached. You may eventually get some corrosion but it is going to take a while. Making sure they are tight will help.

WhatI would do it attach the ground from the battery to the frame. From that same atachment point so to the engine block. There are several unused holes you could run a bolt into - could even be the transmission bolt (yes, I know the trans case is aluminum). Then from the block to the cab. If not already done, runone from the frame to the radiator core support as well. Then make sure you have a good ground to the bed.

Copper anti-sieze isn't a bad idea!!
 

Ken B

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where does the small wire get landed? it wont reach to core support or frame. I will happily extend it if needed. But after dismantling stuff over 3 years some sh#1 gets forgotten....any help would be appreciated

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squaredeal91

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where does the small wire get landed? it wont reach to core support or frame. I will happily extend it if needed. But after dismantling stuff over 3 years some sh#1 gets forgotten....any help would be appreciated

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I believe it goes to the fender. Should be a nut bossed hole in fender on the side for it if I'm not mistaken. I can look at the 85 to be sure
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
where does the small wire get landed? it wont reach to core support or frame. I will happily extend it if needed. But after dismantling stuff over 3 years some sh#1 gets forgotten....any help would be appreciated

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Core support.
 

Ken B

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Thanks. I had 2 brain cells that said frame, 2 that said fender , and 7 cells that said core support. now i had a dim light go off an maybe the old battery had the - terminal closer to the core support.....that would explain the short wire.
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
Thanks. I had 2 brain cells that said frame, 2 that said fender , and 7 cells that said core support. now i had a dim light go off an maybe the old battery had the - terminal closer to the core support.....that would explain the short wire.
Before I posted my response I looked through my photos but didn't have a good one of the battery and the wire, but the one I had showed the wire going towards the front. I ran out of time before going to work to get one of my setup. It looks like you have a photo of the location to bolt it to, so you're good to go.
 

Ken B

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So I have a firewall to engine ground, a core support to frame ground, a battery to core support ground and the lighting grounds on each side of the core support. Am I missing any under the hood??
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
Wouldn't hurt to have engine block to frame, frame to body, battery negative to frame and body, never too many. Even add some extra for the taillights, license plate light(s), anywhere you can from body to frame to complete the path back to battery negative.
 

Old77

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Battery negative to engine block
 

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