Heater Core Hoses and Heating Issues

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AJ 3

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On my new purchased 1979 stepside with a 350 engine I am having an issue with interior heat. Everything works electrically but my VW's seems to blow out hotter heater air than my truck. I have replaced the thermostat with a known working one (I tested it first).

After looking over the heater core hoses they start at the intake manifold. Then run to the heater core and back to the radiator. After looking at my 2003 4.3 Blazer and 1993 305 truck. Both return from the heater core and run to the water pump.

On my 1979 truck I have a plug at my water pump that I could unscrew and run my heater core return there like my other Chevy's. So which way is correct, return to radiator or return to water pump?

Could this quick fix solve my heating issues or do I totally have other issues. Like a plugged heater core or a not working cable somewhere.
 

austinado16

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I don't recommend installing used T-stats. A nice new Mr. Gasket T-stat (top of the line) is dirt cheap. Just because a T-stat tests ok in a pan of water doesn't mean it'll last, be accurate, flow properly, blah, blah, blah.

Regarding the heater, remove the hoses from the core. Foreward flush and backward flush the heater core. Do similarly with the hoses to the engine.
 

chengny

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Deja vu! Another member asked a very similar question yesterday.

Flow through the core is in from the bottom, up through the coils and out the top.

The bottom hose is the higher pressure hose and connects to the nipple on the intake manifold.

The return to the engine is from the top of the core and can connect to either the tapped connection on the water pump or the nipple on the top of the RH side of the radiator. Schematically speaking, in the system the are in the same run of pipe.


See this link for more information/images

http://www.gmsquarebody.com/forum/showthread.php?t=8877
 

Slick51

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Maybe too late to be helpful here, but I just fixed a similar problem with my 1985 c10 with a later model 350. My ducting worked fine and the air blew out of the correct holes, but it never got hot. My problem ended up being that there were 2 ports out of the water pump that I could connect the heater hose to, one to the passenger side (right) and the other to the driver side (left). I had it hooked to the right side of the pump which turned out to be more on the suction side of the impeller. I switch the lines in wammo! Warm air out of the heater. Hope this helps!
 

GreaseDog

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I don't recommend installing used T-stats. A nice new Mr. Gasket T-stat (top of the line) is dirt cheap. Just because a T-stat tests ok in a pan of water doesn't mean it'll last, be accurate, flow properly, blah, blah, blah.
I'm not sure I'd qualify anything with a Mr Gasket logo on it as "top of the line". Stant is the name you want to look for in thermostats.
 

MrMarty51

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Stant is good stuff.
Forwards flush heater core, then reverse, then, blow through with compressed air, very carefully until all the water and sludge is pushed out, then open the air a bit more, reflush, blow, and flush and blow through until water becomes clear.
Intake manifold is pressure side. Also, hook pressure side to lower on the heater core, hot water rises and helps the flow.
 

Joseph Gossec

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There are a number of things that can cause your heater to fail. The first thing you need to figure out is whether or not there is heat available to your car's heating system.
 

HotRodPC

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There is a number of things we don't allow at this forum, and that's SPAMMERS, especially stupid ones that don't even make sense with their post. Buh Bye DipShit !!!

BTW members, This is the 2nd time in less than 7 days this guys has posted and I've banned him within minutes or a couple hours of his post under 2 different ID's now and 2 different IP Addy's.

I know it's the same guy because his siggy has a link to some kind of out of the country Auto Supply website. I don't know if that site is safe so I suggest, DO NOT GO TO ANY LINKS that SPAMMER posts. Simply Report the Post so the first mod on duty can BAN him and get the link removed for the forum.
 

89Suburban

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:lazer:


Sent from my iPod touch 4th Gen using Tapatalk
 

chengny

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Reminds me a lot of another fellow - you know - the one that explained, so well, the function of the engine's cooling system. I have adopted his post as my signature.

Bern Anthony
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--------------------------------------------------------------------------------
His answer to the question: How does the coolant flow?

Your cooling system is what keeps your car from having a meltdown. If you didn't have some way to cool things off, your engine would turn into a solid block of useless metal in no time flat.
 
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HotRodPC

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I deleted the link from your post Jerry. Yes, they are connected. When you find things like that, Please use the REPORT POST feature.
 

HotRodPC

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Now I am trying to find that post. If you can link me to that thread Jerry... so I can find the post. I banned Bern Anthony, now I can't find him in Member list to search his posts. Banning him removes his siggy, so we're good there.
 

HotRodPC

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HotRodPC

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Ok, so that was his only post and now that he's banned and his link is gone. We'll go ahead and leave his advice in that thread. You know how beneficial that is to the forum and to those who didn't know. :rofl: :rolleyes: Seems he only does 1 post per name. He's using different IP Address with each ID he registers with. And the IP's aren't even close so it's not like we can ban a range. I'll get with Shaggy to see how to stop this jerk off. Thanks again for the help.
 

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