Alternator cable routing

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Johnny Atomic

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Sierra Classic
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I have questions about the large cable out of the alternator on the "bat" connector. I see on some trucks they have a large gauge cable from the bat connector to the battery positive. I have an 1983 305 w/ quadradjet. Mine has a cable from the bat connector to same lug on the starter as the large cable going to the battery. I don't think this is original to the truck. It runs down the front of the block and routed underneath the exhaust manifolds to the starter. This looks dangerous to me, I put some split loom around it to protect it from chafing but looks like it could be easily melted from the exhaust heat. I've read that some run this cable from the bat connector, down behind the valve cover, and down the rear of the block through a metal tube to the starter. The 1983 light truck shop manual is not very clear about what the bat terminal is connected to for the LE9, and the routing for that connection. From reading the manual it sounds like the connection from the bat connector goes to the bulkhead.

What was the "bat" connector originally connected to on the other end?? Which way was it routed? What are the advantages and disadvantages of the different methods? What cable would you use? What is the best way to rout it?
 

75gmck25

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Original routing on my ‘75 was with the BAT wire in a plastic loom, clipped to the top of the valve cover, down the back of the engine through the metal tube, and with a fusible link where it connected to the starter lug. There is a 2nd power wire connected to the starter lug, and it runs up through the same metal tube and over to the junction next to the brake booster.
 

JT58

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Mine had the red cable to the starter previously running down to a clip on the front differential, the by the exhaust manifold to the starter. Bad spot with the differential moving up and down and too close to the exhaust manifold. I had a shop do some work and they noticed the issue and gave me a new cable and routed it down along the inside of the frame then over to the starter. Much better this way.
 

84GMCSierra

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Any photos of the factory wire routing for these wires? This is my 84 Sierra. So far I've lucked out and they haven't touched the manifolds.
 

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Ricko1966

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I have questions about the large cable out of the alternator on the "bat" connector. I see on some trucks they have a large gauge cable from the bat connector to the battery positive. I have an 1983 305 w/ quadradjet. Mine has a cable from the bat connector to same lug on the starter as the large cable going to the battery. I don't think this is original to the truck. It runs down the front of the block and routed underneath the exhaust manifolds to the starter. This looks dangerous to me, I put some split loom around it to protect it from chafing but looks like it could be easily melted from the exhaust heat. I've read that some run this cable from the bat connector, down behind the valve cover, and down the rear of the block through a metal tube to the starter. The 1983 light truck shop manual is not very clear about what the bat terminal is connected to for the LE9, and the routing for that connection. From reading the manual it sounds like the connection from the bat connector goes to the bulkhead.

What was the "bat" connector originally connected to on the other end?? Which way was it routed? What are the advantages and disadvantages of the different methods? What cable would you use? What is the best way to rout it?
I can get pics of 2 of mine,but yes down the side of the block behind the exhaust manifold is original,on many years. My 86 is pic 1 a bracket on the frame and the cable routes down by the fuel pump and back to the starter. The 83 has a bracket at the front of the block,I'm pointing to it with a stick. The cable goes in the looped wire bracket then back to the starter, same with my 75.
 

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Ricko1966

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I thought he was talking about the battery positive lead. All three of my trucks the alternator wires run along the passengers side valve cover.
 

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Ricko1966

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And for what it's worth there is almost no difference running the alternator charging wire to the battery positive lug or the starter positive lug. There is only one disadvantage I can think of and it is such a weirdo once in a lifetime situation ,it's not worth the trouble to print and explain.
 

AuroraGirl

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I can get pics of 2 of mine,but yes down the side of the block behind the exhaust manifold is original,on many years. My 86 is pic 1 a bracket on the frame and the cable routes down by the fuel pump and back to the starter. The 83 has a bracket at the front of the block,I'm pointing to it with a stick. The cable goes in the looped wire bracket then back to the starter, same with my 75.
A plastic fuel filter at the fuel pump and a fuel shut off on the (return?) line?

Ricko Its like I dont know who you are anymore
 

Ricko1966

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A plastic fuel filter at the fuel pump and a fuel shut off on the (return?) line?

Ricko Its like I dont know who you are anymore
It's not what you think it is. It is temporary as a test piece. From the factory mechanical pump to the Carbureator is steel line all the way to the carb. Anything rubber or plastic is from pump inlet down,so a leak will most likely result in a puddle under the truck,not a puddle on top of a hot engine dripping onto hot exhaust manifolds,etc..The mechanical pump on the block has no pushrod behind it. And is a 3 port,bypass pump.It is the junction for all my factory lines,but I'm using an electric pump by the tank to push fuel through it. The plastic filter was to verify fuel delivery.The plastic shut off valve is an adjustable restrictor, so I can raise or lower fuel pressure by how much fuel I return to the tank. It is a prototype, not a permanent fixture. The 3 port pump will be a permanent fixture,but near future is going to be in tank TBI pumps, a brass restrictor and just the factory Q jet fuel filter.
P.S. on a factory square if I thought I had to add a clear plastic fuel filter,right here is where I'd want it,inlet side of the pump. So a hole in a fuel filter or hose the pump would draw air and the engine die. Instead of pressire side of the pump so a hole in a filter or piece of rubber hose becomes a squirt gun spraying fuel everywhere on top of the engine until it catches fire or you by dumb luck you've arrived at your destination and turned it off before it caught fire.
 
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