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Cantedvalve

69/70 heater hoses w/o AC. which one is in and which one is out?

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Talking about the holes in the firewall.  I am going to attempt to reconnect my heater at the urging of my son (core has been replaced previously), and I am making some SS hard lines.  Given the way I have to bend them, I have to get it right the first time.  So which one, top or bottom, is the feed line (which on a Cleveland, connects to the block behind the alternator)?

By process of elimination, I can figure out which one is return :)

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Okay, my research says the LOWER hose (as seen at the firewall) is the feed, where the upper is the return. The explanation I found was that this helps eliminate air from the system.  Anyone care to agree or disagree?

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9 hours ago, RPM said:

Right you are Karnac. 

But since you're not trying to cool the fluid like in the radiator, does it really matter?

Heater core is not for cooling the fluid but it is for getting the heat out of the fluid to heat the cabin. If there is air in the heater core, then less heat will be extracted. This may not be an issue for you in Cali but people who live in colder areas may like to get the most heat from their heater.

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Hey, I agreed with CV on the correct line routing and the difference from a radiator. I'm just saying the heater core can't be the only place in the system where you might get an air pocket, and it wouldn't be the end of the world if you happened to hook them up backwards. 

And btw, it does get chilly here in Cali. Just the other day it got down into the 40's and I had to turn on the heater :)  Got so hot I had to turn it down. 

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That is optional , you don't have to, all cars imported into the country which are over 35 years old can stay lhd.

At that show over 500 cars and about 10% of them were converted rhd.

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On 11/28/2018 at 7:48 AM, aslanefe said:

Heater core is not for cooling the fluid but it is for getting the heat out of the fluid to heat the cabin. If there is air in the heater core, then less heat will be extracted. This may not be an issue for you in Cali but people who live in colder areas may like to get the most heat from their heater.

Well I just found out that my 70 351w heater hoses are reversed.  HaHa they have been that way forever.   I don't see how this could affect anything.    

418w.jpeg

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Don't tell anyone Alan, but mine are too. It must be doing some serious damage as the heater keeps me quite toasty with the lever halfway between cool and warm, and the motor will idle all day long at 185* and hit195-200* while driving. I'd switch them but one hose is too short. C'est la vie.

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On 12/21/2018 at 10:21 PM, Alan_Mac said:

Well I just found out that my 70 351w heater hoses are reversed.  HaHa they have been that way forever.   I don't see how this could affect anything.    

 

If you do not have air in your heater core, there won't be any effects. If you have air in the heater core, you won't get as much heat out of the heater.

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