heater hose routing - The 1947 - Present Chevrolet & GMC Truck Message Board Network

RED72blazer · 09-15-2003, 12:45 PM

Does anyone have any diagrams on how to route the heater hose in the engine bay? I recently swaped a four core radiator in and it has an extra nipple for a heater hose. I also am putting in a new engine and need to decide where the outlet should be on the manifold or water pump or should I have one go to the radiator and one go from the top of the pump to the manifold and then from the manifold to the heater box?

red72

RED72blazer · 09-17-2003, 06:04 PM

I guess it's not how to route the hoses it's where to connect the ends to the engine. I know I have to connect one to the radiator. Should I just plug the one on the water pump or the manifold? Does anyone have any pics of an engine compartment with a four core radiator?

chaptr2 · 09-19-2003, 12:00 PM

Here is a very clear picture of how it should route. One goes to the manifold and one to the water pump. I hope this helps.

bpmcgee · 09-19-2003, 12:21 PM

Chaptr,

Are you sure that's right? My top hose matches yours, but my bottom hose goes to the radiator.

Brian

red71cheyenne · 09-19-2003, 01:48 PM

No, my 71 is the same way. Except the manifold one comes off the TPI! Same difference though. I know you can't see the bottom hose, but its coming off the water pump. I think you can just plug the outlet on the radiator. My original radiator had an outlet that was plugged.

chaptr2 · 09-19-2003, 02:44 PM

God I hope it’s right. Just kidding.

That is the way it is set up, but I bought my radiator from a parts store and it didn't have anything going that goes to the radiator besides the big radiator hoses and my trans lines. If the heater hose goes to the radiator, I don't have an outlet for it.

The main reason for posting was to show the way my heater hoses go. My upper goes to the manifold and the lower goes to the water pump. Plus nobody helped Red71Blazer out for four days, so I figured I would try to help out.

bpmcgee · 09-19-2003, 03:54 PM

Chaptr,

Sorry, wasn't criticizing, just wondering if I'd found another place that the POS PO bastagized my truck.

Brian

chaptr2 · 09-19-2003, 06:23 PM

I was just teasing. I think mine is only a 3 core and that is why I probably don't have a fitting on my rad.

Bpmcgee don't take any offence. I was just being sarcastic. If you were standing next to me I would have put my elbow in your side as I was teasing you.

bouncytruck · 09-19-2003, 07:34 PM

I just bought a new 4-core to replace my 3 core and my heater hoses don't come off the radiator. I think mine are just like chaptr2 - except I don't have a blower, braided hoses, shiny headers or a clean paint job on my block

RED72blazer · 09-20-2003, 03:54 PM

thanks guys, I guess I'll just plug the one on the radiator and go off the manifold and water pump

**1970cstblazer** · 09-20-2003, 05:30 PM

This is the hose routing on my '70. I replaced the original ribbed GM heater hoses a few years ago, but this is the exact routing with the little steel bracket connecting them.

09-15-2003, 12:45 PM	#1
RED72blazer urban fourwheelin Join Date: Aug 2002 Location: Seattle Posts: 1,007	heater hose routing Does anyone have any diagrams on how to route the heater hose in the engine bay? I recently swaped a four core radiator in and it has an extra nipple for a heater hose. I also am putting in a new engine and need to decide where the outlet should be on the manifold or water pump or should I have one go to the radiator and one go from the top of the pump to the manifold and then from the manifold to the heater box? red72 __________________ 1972 K5 Blazer with Cummins 4BT, NV4500 swap in the parts gathering stage. Last edited by RED72blazer; 09-16-2003 at 03:49 AM.

09-17-2003, 06:04 PM	#2
RED72blazer urban fourwheelin Join Date: Aug 2002 Location: Seattle Posts: 1,007	I guess it's not how to route the hoses it's where to connect the ends to the engine. I know I have to connect one to the radiator. Should I just plug the one on the water pump or the manifold? Does anyone have any pics of an engine compartment with a four core radiator? __________________ 1972 K5 Blazer with Cummins 4BT, NV4500 swap in the parts gathering stage.

09-19-2003, 12:00 PM	#3
chaptr2 Registered User Join Date: Mar 2000 Location: Olalla, WA Posts: 705	Here is a very clear picture of how it should route. One goes to the manifold and one to the water pump. I hope this helps. Attached Images __________________ This is only my opinion and it is subject to change. 70 GMC Short box stepside Blown 388 Stroker 72 K/5 Blazer 350/SM465/205

09-19-2003, 01:48 PM	#5
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	No, my 71 is the same way. Except the manifold one comes off the TPI! Same difference though. I know you can't see the bottom hose, but its coming off the water pump. I think you can just plug the outlet on the radiator. My original radiator had an outlet that was plugged. Last edited by red71cheyenne; 10-04-2007 at 08:36 PM.

09-19-2003, 02:44 PM	#6
chaptr2 Registered User Join Date: Mar 2000 Location: Olalla, WA Posts: 705	God I hope it’s right. Just kidding. That is the way it is set up, but I bought my radiator from a parts store and it didn't have anything going that goes to the radiator besides the big radiator hoses and my trans lines. If the heater hose goes to the radiator, I don't have an outlet for it. The main reason for posting was to show the way my heater hoses go. My upper goes to the manifold and the lower goes to the water pump. Plus nobody helped Red71Blazer out for four days, so I figured I would try to help out. __________________ This is only my opinion and it is subject to change. 70 GMC Short box stepside Blown 388 Stroker 72 K/5 Blazer 350/SM465/205

09-19-2003, 12:21 PM	#4
bpmcgee Registered User Join Date: Mar 2003 Location: Northern Illinois Posts: 2,181	Chaptr, Are you sure that's right? My top hose matches yours, but my bottom hose goes to the radiator. Brian

09-19-2003, 03:54 PM	#7
bpmcgee Registered User Join Date: Mar 2003 Location: Northern Illinois Posts: 2,181	Chaptr, Sorry, wasn't criticizing, just wondering if I'd found another place that the POS PO bastagized my truck. Brian

09-19-2003, 06:23 PM	#8
chaptr2 Registered User Join Date: Mar 2000 Location: Olalla, WA Posts: 705	I was just teasing. I think mine is only a 3 core and that is why I probably don't have a fitting on my rad. Bpmcgee don't take any offence. I was just being sarcastic. If you were standing next to me I would have put my elbow in your side as I was teasing you. __________________ This is only my opinion and it is subject to change. 70 GMC Short box stepside Blown 388 Stroker 72 K/5 Blazer 350/SM465/205

09-19-2003, 07:34 PM	#9
bouncytruck SKINNY TIRES RULE! Join Date: Sep 2001 Location: Bothell, WA Posts: 11,049	I just bought a new 4-core to replace my 3 core and my heater hoses don't come off the radiator. I think mine are just like chaptr2 - except I don't have a blower, braided hoses, shiny headers or a clean paint job on my block __________________ bouncytruck 1972 K5 The Hauler 1994 K1500 Suburban The Daily2010 Kia Soul Wife's Ride2014 Fiat 500L

09-20-2003, 03:54 PM	#10
RED72blazer urban fourwheelin Join Date: Aug 2002 Location: Seattle Posts: 1,007	thanks guys, I guess I'll just plug the one on the radiator and go off the manifold and water pump __________________ 1972 K5 Blazer with Cummins 4BT, NV4500 swap in the parts gathering stage.

09-20-2003, 05:30 PM	#11
1970cstblazer All stock and staying that way Join Date: Jul 2003 Location: Elkland, PA Posts: 1,283	This is the hose routing on my '70. I replaced the original ribbed GM heater hoses a few years ago, but this is the exact routing with the little steel bracket connecting them.



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