Heater hose port possibly clogged?

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Dreadknot

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Dec 15, 2017
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Location
Dallas
My Car
1971 mach 1
I was getting no heat from heater core. So i pulled the hoses and flushed both ways with no issues. So I dumped water into the port that goes into the block and the water goes nowhere it just sits. Is this port clogged? Does the engine need to be running for it to push coolant through?



 
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Till the pump moves the coolant around, the coolant stay wherever gravity laws and air pressure (vacuum) are keeping it from returning to the lowest possible point.

When you will start engine again after a refill at radiator, set temp inside to highest, stop after few secs to refill.

You can also to minimize air in system during refill with radiator open and almost full, by applying pressure/gently pump on the highest radiator hose, like a sponge, till you hear/feel no bubbles. The radiator level will get lower as air gets removed out of the circuit.

 
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That was also my initial thought. I figured i had air trapped in the system. So I completely dumped the system before pouring water into that port. The port refuses to drain into the block.

 
Just for giggles I put a tube on the port and blew into it. Pushed the water through and back up into the block. It wouldn' drain because it turns up to the t stat not down into the block. So now I' back to square one with why I have no heat in the heater core. Perhaps I had a bigger air bubble than I thought.

 
Its been a while since I've played with coolant on an open 351 engine.

All I know is that there is still a lot trapped in the heads. Even after you flush the system. That might be why it comes back to level, after you blew it tho, it can be coolant, not the same bits of coolant you think is coming back. If you blow with air, keep only one exit open at a time and the one you want to test.

here some pict showing how coolant stays trapped in upper block

http://351c.net/board/index.php?/topic/3781-excellent-description-of-the-cleveland-cooling-system-and-bypass/

If you want make sure it flows other than blowing with air, and have the possibility to do it. Hook a water hose, and flush it, you will see

if water comes out normally or if debris are in it. If the coolant was in there for a long time, you may get some brownish juice out

first, but that's normal if system has not been flushed for a long while. On a 327 from a 67 Camaro that was parked for 10 years, I've seen coolant coagulated like old blue blood. Took a while but eventually water came out clear at some point and the "jelly" was gone.

You need of course to have some outdoor option to do this and nice weather would be handy. Even if you try your best, its gonna be a real (cold) wet mess :)

 
ok dumb question but are you having any overheating problem with the engine at all? What temp is the thermostat on the radiator.

 
That post was a good read for sure. No overheating. it does take forever to warm up the motor. But after some decent searching I also found i dont even have the proper thermostat. The car runs just fine just cant get any coolant to flow through the heater hoses and I'm 100% positive it not clogged. The thermostat I pulled out was a 180.

 
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ok so a couple simple checks, start the motor and warm it up, use a laser temp gauge and see what you're getting off the engine, monitor the hoses into and out of the radiator, when the water temp hits whatever the thermostat is set for it should open and water should begin to flow through the entire system. If the temp doesn't get to be the same on both hoses and over the thermostat temp stated then its probably just a bad thermostat. Its odd the engine doesn't overheat if it is but possible, especially if maybe you're in a really cool climate or the heat generated from running is being dispersed via other means very efficiently.

 
also oddly enough it could also be a thermostat stuck partially open, that would explain the taking forever to heat up to temp yet never actually producing heat.

 
I will pick up a correct thermo from napa and refill the system in the morning. It s been about 65 degrees here for the last few weeks. Nothing too cold.

 
let us know, I'm putting money on a stuck thermostat and the 5 dollar parts fixes all your issues with it.

 
You probably won't find the "right" thermostat at napa, They will give you a Windsor T-stat. Clevelands have a different t-stat because they have a little hat on the bottom that block a port below thermostat to redirect coolant flow. Don't be fooled by the Mr. Gasket T-stat either. I had to get the "correct" one off ebay. Good luck!!

 
So a new thermostat and fresh coolant seemed to solve to issue. I assume i just had a large air pocket or the thermostat was causing issues. But iv got heat for winter and that's all I care about.

 
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