ConcoursMustang Forums

1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1967 Mustang => Topic started by: BKnapp on November 15, 2017, 12:08:28 AM

Title: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 12:08:28 AM
I am in the process of cleaning my valve up. The bottom surface that mounts to the bracket has an opening with a recess around it (the repop I have has a closed bottom). Am I correct in assuming there should be a washer/gasket between the base of the valve and the bracket? If so, what material? If there was one there, it isn’t now.

Thanks
Title: Re: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 08:58:17 AM
Thanks again, Bob! I always appreciate the help!!

First, I apologize for posting in the wrong year...have been reading too many threads and lost track of where I was. My application is a 1967, so this can be moved or deleted as the higher powers see fit.

This is what I am referring to
Title: Re: Re: Heater Control Valve Repair?
Post by: Bob Gaines on November 15, 2017, 12:22:57 PM
Thanks again, Bob! I always appreciate the help!!

First, I apologize for posting in the wrong year...have been reading too many threads and lost track of where I was. My application is a 1967, so this can be moved or deleted as the higher powers see fit.

This is what I am referring to
For 67/68 the bottom of the valve gets a rubber"O" ring. It is easily Hardware store sourced.
Title: Re: Heater Control Valve Repair?
Post by: 67gta289 on November 15, 2017, 12:45:31 PM
Make sure that the valve physically moves when vacuum is applied and then again when it is removed.  If the valve does not move, and if you can't get it to move, then you will need to look for a replacement.
Title: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 02:13:29 PM
Thanks guys...and thanks for correcting my error Bob.

I am pretty sure it opens and closes properly, but will test when done cleaning. I am glad I asked and will take a closer look at it..I just took it apart last night. In my hands it was hard to tell what was sealing it, other than a bead of crud. In the picture it almost looks like cork. I didn’t want to get too aggressive until I have more info. I will clean it up and pick up an O ring.

I picked this up from WCCC...coincidently it was stamped 11-66, which coincides nicely with my December built engine and other date stamps I am finding.

I always appreciate the help.
Title: Re: Heater Control Valve Repair?
Post by: Bob Gaines on November 15, 2017, 03:36:43 PM
Before you go much further with cleaning etc.you need to make sure it is usable. If the vacuum pod does not hold vacuum it is worthless. The quick test is to create vacuum by sucking on the nipple. Quickly put your finger over the nipple. It should hold vacuum and not move until you take off your finger . If it releases slowly then it has a leak and is worthless. The vacuum pod are not designed to be rebuilt .
Title: Re: Heater Control Valve Repair?
Post by: 67gtasanjose on November 15, 2017, 04:07:36 PM
... If it releases slowly then it has a leak and is worthless. The vacuum pod are not designed to be rebuilt .

TRUE, to a point. Function-wise, yes, it would be worthless but if you never need the A/C, your HEATER will operate just fine!
Title: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 04:14:44 PM
Thanks Bob and Richard. WCCC said they tested and does hold vacuum, but I will confirm. Is there any way to test whether or not the water flow is sealed, other than hooking it up?
Title: Re: Heater Control Valve Repair?
Post by: 67gta289 on November 15, 2017, 04:32:20 PM
You should be able to see the gate assembly move (fully) when vacuum is applied, and return (fully) when removed.   This will be enough of a flow restrictor, does not need to provide 100% shut off capability to get the job done.
Title: Re: Heater Control Valve Repair?
Post by: Bob Gaines on November 15, 2017, 06:47:04 PM
You should be able to see the gate assembly move (fully) when vacuum is applied, and return (fully) when removed.   This will be enough of a flow restrictor, does not need to provide 100% shut off capability to get the job done.
+1. In fact the 69 version has holes drilled into the valve plate so that 100% sealing is not a possibility
Title: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 08:29:43 PM
I placed a vacuum hose over the nipple, applied vacuum, and clamped the hose. It stayed closed for over an hour, so I assume I’m good. Thanks for the tip. Still need to clean the recess out, but it sure looks like hardened cork
Title: Re: Heater Control Valve Repair?
Post by: 67gta289 on November 15, 2017, 08:40:43 PM
So you don’t have a vacuum leak, that is good for engine performance.  Did you see the valve guys move?
Title: Re: Heater Control Valve Repair?
Post by: BKnapp on November 15, 2017, 08:57:14 PM
Yes, the gate closed...moved up,,,and stayed in that position until I released the clamp.