AC heater box valve

[Jengel451]

Quick question. How critical is the valve sealing on this? The valve housing doesn't leak at all, but on the "off" position the valve does let some air through when I blow through it.

Deal breaker? Or can I live with it letting a small amount of coolant through that side of the core?

 

[david hill]

If it is letting a small amount of coolant though that means the sealing edges of the valve are eroding away. Can you still drive it, yes . Is it time for replacement. If one is now available, do it now.

 

[live4theking]

I would replace it since you have it torn apart. So, when you turn AC on the linkage opens the valve to allow some coolant to flow through which is to keep the evaporator core from freezing up.

 

[Jengel451]

I would replace it since you have it torn apart. So, when you turn AC on the linkage opens the valve to allow some coolant to flow through which is to keep the evaporator core from freezing up.

I've honestly been trying to figure that one out. The Control Valve on the firewall opens just a little when it gets too cold. Sort of get that, but the heater core is AFTER the evaporator, so I could never understand just how effective that is.

The valve on the heater core only opens when the door is activated on the front of the box, and it only let's hot coolant into the one half of the core, the other half is always getting full flow, so I'm struggling with the entire thing honestly.

I get the "You're in there just change it", timing is getting to be an issue, i'm in the middle of BFE and getting anything is a total cluster that takes over a week, I have everything here to put the new core and evap in the box and bolt back in, then fire up the new engine.....getting a little impatient is a problem I have too.

That being said, I ordered a new one, should arrive in almost 2 weeks.

 

[live4theking]

I've honestly been trying to figure that one out. The Control Valve on the firewall opens just a little when it gets too cold. Sort of get that, but the heater core is AFTER the evaporator, so I could never understand just how effective that is.

The valve on the heater core only opens when the door is activated on the front of the box, and it only let's hot coolant into the one half of the core, the other half is always getting full flow, so I'm struggling with the entire thing honestly.

I get the "You're in there just change it", timing is getting to be an issue, i'm in the middle of BFE and getting anything is a total cluster that takes over a week, I have everything here to put the new core and evap in the box and bolt back in, then fire up the new engine.....getting a little impatient is a problem I have too.

That being said, I ordered a new one, should arrive in almost 2 weeks.

TWO WEEKS wow that's crazy.

 

[volksworld]

i think the deal is that when the a/c door is opened it shuts down half the heater core...so when the heater control valve on the firewall opens to prevent freeze up the heater core doesnt overpower the evaporator core...the heater box was enough of a pia to r&r that the last thing i wanted to do was take it out again so i bought a new valve...with my luck it will be defective...

 

[live4theking]

My new valve peed all over the floor so be sure to test it prior to installing it.

 

[Jengel451]

My new valve peed all over the floor so be sure to test it prior to installing it.

Where did it leak from?