1969 c10 heater core question

[frank linkh]

Lame

 

[DeanMk]

Easy fix... buy a Ford. It won't even start when it's cold so no need for a heater core. Leave it in the driveway and drive the wife's Dodge til spring.

Under no circumstances should you attempt to replace the Ford's heater core... if God wanted your windshield defrosted and the passenger side floor less rusty, He wouldn't have made it so cold and wet... I think that's in the Scriptures (revised).


ETA: Oddly, I feel the need to clarify... I mean the above only as a joke. A good-natured ribbing at brand loyalties. Also, I'm 100% sure that God's own hand impacting frozen windshields or rusty cab floors is never mentioned (even once) in The Bible.
Lotsa butthurt going around lately, I'd hate to be the cause of a CTE...(Catastrophic Triggering Event).

You know why that is, Johnny...don't you?
Because you can't fix a heater core with a hammer, a screwdriver and a 7/8" wrench!

 

[gmerkt]

I'm mostly a Ford guy, haven't had many GM products. But engineering principles apply equally. Here is my experience in this connection with heater cores and radiators. The design of the core itself has a regulating effect on coolant flow through the core. If your original core is of a honeycomb design, those allow the coolant to percolate through more slowly. So you get the full value of the heated liquid passing through the core. If you replace a honeycomb core with a tube-type core, the coolant will flow through too fast and you won't get much heat extracted out of it and onto the windshield. So maybe this is why you have seen some instructions that refer to a restriction disk or whatever. Same comment applies to GM cars that had honeycomb radiators decades ago. Honeycomb core material costs more than tube type, therefore some radiator shops would recore with the latter. Which created overheating problems in such cars because the coolant would pass through too quickly and wouldn't get the proper heat sink factor.

Or, and I don't know this, it's possible that original heater cores of the tube type may have had some kind of restriction built into the inlet tank that would slow down the passage of coolant for the reasons stated above. Sometimes replacement parts don't have the same exact features/specs that orig. factory stuff had. Once you get the core size issue worked out, install the core and see how it performs. If it seems to run cool, then the fluid is passing through too quickly. This can easily be remedied by removing the inlet hose and installing a washer of proper o/s diameter so that it lodges in the hose but won't pass any further. You can regulate this as necessary with different size inner hole as you try this out.

Here's a tip for using your heater core as a heat sink booster for the radiator. If you are pulling a heavy load up a hill and see your engine temp. gauge going up, turn on your interior heater full blast and open a window. The heater core will take an extra measure of heat out of the engine coolant just like the radiator does.

 

[Jonnyuma]

You know why that is, Johnny...don't you?
Because you can't fix a heater core with a hammer, a screwdriver and a 7/8" wrench!

So THAT'S where I went wrong... 15/16"?
Please don't say metric... that's just weird and kinda gross.

 

[jbett98]

Rambler had a lever on the instrument panel that when moved, shunted the heater cores hot air to the outside, so it could help cool down an overheated engine.
It was called a "Weather-Eye".