Urgggh, No Heat after Flush!

stubs300

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Long story short, 66-300 w/ac. Getting ready to move and did a 3X flush on the cooling system last month. Flush, fill, drive, cool, flush, repeat. Like I said, did that 3 X and doing this I also had the heat on to circulate thru the system and the heater worked fine! Took it out today for a spin and have no heat. The temp control cable moves the actuator so it does move from 1 end to the other no problems. All other actuators work going from ac/ max ac/ heat, defrost, etc. but still no temp change. Both hoses going to/from engine to firewall are the same temp. However, the short hose from each fitting at the firewall is cool. Looks like a bypass hose or something? I'm thinking that I'll have to flush the heater core from both those fittings and focus on the heater core alone. Ideas, hint's, tips, whatever's? Thanks
 
Hopefully it'll be a simple fix for you.
 
Go to a "do it yourself" car wash..
Remove heater hose from both sides of heater core...
Start up wash..
Stick in one side for couple..
Then other side for a couple..
Then back to otther side for a couple..
And thennn, back to other side for a couple...
Put heater hoses back on...
Fill radiator ..
Drive car..... :)
 
Go to a "do it yourself" car wash..
Remove heater hose from both sides of heater core...
Start up wash..
Stick in one side for couple..
Then other side for a couple..
Then back to otther side for a couple..
And thennn, back to other side for a couple...
Put heater hoses back on...
Fill radiator ..
Drive car..... :)
That will work, you have to be cautious about how much pressure you put to the heater core though. We have a flush tool at work that puts air behind the stream of water but never give it full line pressure(150 psi). Just quick bursts about 25-40 psi.
 
The hoses going to the heater core on your car first go to a valve. From what I can tell it is a bimetallic valve that allows more flow as the coolant temp increases. That would be the hose on the lower right side of the firewall looking at it from the front of the car. The short hose is the supply to the heater core. In the heater box there is also another control valve that is opened by the cable. What you may have to do is split the system into it's 2 parts. Disconnect the 2 hoses from the heater core, those will be the 2 by the valve cover, hook up garden hose where the short hose goes, you should have good flow through the core if the control valve is open. If not you will have to go from that point.
 
If you flush heater core. First flush it to reverse flow, so you dont push rust etc deeper into core.
 
Go to a "do it yourself" car wash..
Remove heater hose from both sides of heater core...
Start up wash..
Stick in one side for couple..
Then other side for a couple..
Then back to otther side for a couple..
And thennn, back to other side for a couple...
Put heater hoses back on...
Fill radiator ..
Drive car..... :)

UUmm, NOPE, that's not going to happen as car washes have rules against that!
 
The hoses going to the heater core on your car first go to a valve. From what I can tell it is a bimetallic valve that allows more flow as the coolant temp increases. That would be the hose on the lower right side of the firewall looking at it from the front of the car. The short hose is the supply to the heater core. In the heater box there is also another control valve that is opened by the cable. What you may have to do is split the system into it's 2 parts. Disconnect the 2 hoses from the heater core, those will be the 2 by the valve cover, hook up garden hose where the short hose goes, you should have good flow through the core if the control valve is open. If not you will have to go from that point.

I've read this 5 times now and it still make no sense whatsoever. There's a short hose that looks more like a bypass then anything else as the 2 are tied together before it goes into the wall!
 
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This is the valve on the lower left of the firewall. The hose from the water pump goes to the lower port of the valve, the short hose comes out of the upper port going to the heater core. Hope this helps.
 
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