My heater won't work on my 71 mav, A/C works great and all the other functions are fine on the control panel. I checked my heater control valve and noticed it was kinda stuck so I turned on the heater and manually pushed down the lever on the control valve and the heater worked great. Do I need to change the control valve? Is there a cheaper one than this $70 piece? Also, is it hard to change? Because it looks like I'd have to drain the coolant.
Pinch off the hoses then remove the old one.(minimal coolant loss that way)post an add on the forum...betcha someone has a good one to sell.Or go junk yarding.Should be able to find one in any ford/lincoln/merc with A/C of the era,just gotta hope you find a good one.
So nothing wrong with my vacuum lines right? Any way I can test it? I am gonna go looking for one anyway though. what about this one, can I use this one instead? http://shop.oreillyauto.com/ProductDetail.aspx?MfrCode=FAA&MfrPartNumber=74612
what you need to know is what valve it is...norm open/closed... these valves work both ways. my valve will close when i start the car...when i turn the heater on, it opens... you are on the right track to find one. i have a black plastic one on my Mav. ...Frank...
to check...start the car, there should be vac. on the hose. turn the heater on..no vac. ...:Handshake...
you may want to flush the heater core while you're at it. just take both heater hoses off at the engine. run water through one hose and then the other. do this untill the water is clear. change the valve and all you have lost is the coolant in the heater core. ......
nice! that sounds simple. got it . . . and sweet idea about pinching the hoses, so simple but saves me a lot of time.
Could I purchase this one instead? I see it on the parts list of the 1976 cars. Does it have the vacuum regulator on it as well? This is thing is like $12!
I bought a NOS Maverick valve off of eBay for less than $25. They are out there, just have to look around...
I am running one of those. There are two vacum lines running through your firewall if you trace them you will find that they both go to a T and the upper one has a cutoff valve inline "water valve vacuum switch"(you can see it on the front of your heater box ) all it does is is allows the valve to open more when the heater is in certain positions (defrost compared to floor whatever) but they both come from the same vacuum scource.
I got the problem fixed. Check out the write up: http://mmb.maverick.to/showthread.php?p=533574#post533574