LS motor coolant line routing

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347strokin

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Hey guys! Well been busy with a bunch of other things but finally have some more time to put into the truck.

Can someone steer me in the right direction on my coolant line routing?

I've included two pics. I believe in the first pic, the coolant runs from the water pump to the lower rad fitting.

In the second pic, I believe the coolant should run from the water pump to the upper rad fitting.

And back to the first pic, you can see my heater core hoses are already run to the water pump. Now what do I do with the smaller upper rad fitting just below the over flow fitting? Should I just plug that? I think it originally went to the heater core.

Thanks a million!

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foamypirate

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You've got it right. You will cap the small port below the radiator cap.

You can see it capped off on my swap:

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cooperhw

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True, but you do have a steam line coming off the drivers side head @ the front of the engine that has to go somewhere. Factory sent it to the radiator, most guys put it into the top of the water pump.
 

cooperhw

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I can take a pic of the ls in my El Camino eater lines if you want?
 

foamypirate

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True, but you do have a steam line coming off the drivers side head @ the front of the engine that has to go somewhere. Factory sent it to the radiator, most guys put it into the top of the water pump.

I've got mine tapped into the top of the water pump. I'm using a Camaro LS3 pump, so there is a nice spot for it. You can just see the brass barb sticking out the back of the upper hose area of the pump:

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347strokin

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You've got it right. You will cap the small port below the radiator cap.

You can see it capped off on my swap:

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Awesome, thanks! Easy peezy. Clean install too.
 

347strokin

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R15
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350
True, but you do have a steam line coming off the drivers side head @ the front of the engine that has to go somewhere. Factory sent it to the radiator, most guys put it into the top of the water pump.

Thanks for the info, I ran that back into the water pump.
 

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