Heater Hose Valve

[BrdWAtti2d]

Ok had a little issue last Friday. In the upper heater hose is a valve that seems to restrict the flow through the heater core. This valve cracked where it connects to the hose. I took the valve out of the line and reconnected the heater hose without the valve in place and got the car home. So I have two questions, first what does the valve do, other than the obvious of restricting coolant flow, and second will it do any harm to drive the car until I can find a replacement?

[Rob B (shoebox)]

It is a restrictor, like you say. Others have left it off permanently without any apparent problems.

[BrdWAtti2d]

Thanks Rob!

[Jeff_in_Atl]

I actually think it may have a purpose. On my old Mustang I put a B302 cam in it. It regularly saw 6000 rpms. After I put the cam in it I had to replace the heater core every 4 years without fail. What a PITA a heater core is in a Fox body Mustang/Capri. It kept blowing a hole in it then it would steam the windshield. I think that flow restrictor is to keep this from happening. I wish the Mustang had one on it. I'd try and find another one if I were you.

[BrdWAtti2d]

Yea that makes sense and yea I plan on replacing it. I was more worried about the short term effect until I can replace it. It's a new heater core so hopefully it will hold up to a couple days worth of abuse. That's pretty much the only place the system could have popped. I've been chasing leaks for months now and pretty much everything else has been replaced. Like they say, a chain is only as good as it's weakest link, looks like that was it. I should have replaced it when I did all the hoses, hindsight is 20/20.