Heater Questions
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
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From: Central Texas
Heater Questions
My 1981 355's engine temperature runs between 195 - 210 degrees. I am not getting much heat from my heater. I think I have something connected wrong in the vacuum circuit. Maybe the valve under the dash glove box? I remember there was some confusion on which of the two hoses connected to that valve. And the heater water valve is connected to the white striped hose.
Craig
Craig
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
I see on the Willcox website the heater diagram. If the two hoses are swapped at the valve under the dash what would happen?
Last edited by Street Rat; Mar 15, 2019 at 01:53 PM.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
I took the white striped hose off of the hot water valve in the engine compartment and plugged it.
I think I should be getting heat all of the time now.
The air in the cabin is definitely hotter now so I guess I'm on the right track now.?
I guess my hoses (white stripped/solid black) on the activation switch must be reversed?
I probably have answered my own questions now.
I'll take more information from anyone.
I think I should be getting heat all of the time now.
The air in the cabin is definitely hotter now so I guess I'm on the right track now.?
I guess my hoses (white stripped/solid black) on the activation switch must be reversed?
I probably have answered my own questions now.
I'll take more information from anyone.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
I swapped the hoses around on the heater control switch under the dash. Hooked the white line to the heater valve and the farthest back port on the switch The black hose I hooked to the center port of the switch. The farthest port forward must be a vent?
This configuration worked...
1st most forward port on switch -vent
2nd or center port on switch - vacuum (black hose)
3rd or most reward port on switch - heater valve (white striped hose)
This is not the configuration that is shown in the AIM.
Comments?
This configuration worked...
1st most forward port on switch -vent
2nd or center port on switch - vacuum (black hose)
3rd or most reward port on switch - heater valve (white striped hose)
This is not the configuration that is shown in the AIM.
Comments?
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Just my opinion, but I always thought that the heater control valve should have never been operated by vacuum. There are way too many things run off of vacuum anyway. I think a clever engineer would have run a steel cable / wire to that valve from the dash controls like most of the cars from the 60s had.
If you are not concerned about originality, I think I would just remove that pc of crap valve and put a manual heater hose valve in its place. I only open my valve in spring and fall, for defrosting, and closing it the entire summer.
If you are not concerned about originality, I think I would just remove that pc of crap valve and put a manual heater hose valve in its place. I only open my valve in spring and fall, for defrosting, and closing it the entire summer.
Race Director
Joined: Mar 2017
Posts: 11,960
Likes: 4,518
From: Virginia
I love the vacuum headlights, and think they are cool AF. I'm yanking all of the vacuum controlled HVAC components, though.
The valve (75 and up) is normally open, so loss of vacuum will still let you get heat. I am super impressed that the rest of your components work well enough that even your heater valve works. Either way, I strongly agree with HeadsU.P. Get rid of the valve, and put in a manual valve, or just convert over to bypass/plug mode in the summer. But I like to keep it simple. If all your original parts work, that's pretty cool too!
The valve (75 and up) is normally open, so loss of vacuum will still let you get heat. I am super impressed that the rest of your components work well enough that even your heater valve works. Either way, I strongly agree with HeadsU.P. Get rid of the valve, and put in a manual valve, or just convert over to bypass/plug mode in the summer. But I like to keep it simple. If all your original parts work, that's pretty cool too!
