16valver

The heater on my 87S is stuck on again.

This happened last summer and I fixed it by some miraculous toying with vac lines on the side of the heater core (you see when the glove box is removed)

Anyway, the valve doesn't appear to be getting vacuum. I popped the vac line off that goes to it and felt no pressure/suction.

Until I figure out what went wrong, would it be acceptable to use a zip tie or metal wire to tie the valve closed? Through research I found that this is basically what people do to the early cars with the manual cable set up, but this is a late car with the vacuum set up. I just want to verify that I won't hurt the cooling system, or risk blowing the valve in some way.

MB968

I'm no expert on this, so hopefully someone else will reply with a little more experience. But, I can't see where blocking the heater valve would be an issue. It's really no different than if you kept the temp off all the time.

The only caution I'd have is to make sure that you don't leave any vacuum lines open where you could have a vacuum leak.

Butters944

My heater valve slider is totally F'd up in my car's cabin and not connected at the valve so, living in AZ and not ever needing heat anyway, I just reached back there in the engine bay and put it to the off position. I don't see anything wrong with doing that.

Carlsbergas

just saw this topic, i just zip tied my heater valve today to fully closed position, cause when its 87 degrees and 50% humidity getting hot air in the cabin isnt a great feeling, drove around and everything looks ok for now, btw mine is 951 1989 turbo s

16valver

Yes I was thinking the same thing in regards to it being no different than simply running it with the switch constantly at cold, which is exactly what I have been doing up to this point.

I am still worried that it may or may not need to be open during start up for pressure reasons. I appear to have one of the crappy plastic valves at the moment so I'm cautious whenever I mess with it.

I have a feeling that a vacuum leak might be the root of the problem. I intend to dive into that asap. Gotta get this thing to keep from blowing 200º air on me first...hah.

I also see you are from Portland!!! I wonder if I've seen you around before... Not many 968's in these parts...

I don't see anything wrong with it either, but I would guess that the early and late valves are different, so I'm just exercising caution before I contort a fragile plastic valve that has burning hot coolant trying to push through it.

16valver

Sweet this is good input!! I think my core might have a leak somewhere too, so I'll be weighing out the advantages and disadvantages of a block off plate in the near future

If anything weird happens be sure to let us know. I'm thinking I'm just about in the clear to commence with operation zip tie.

StickShift

I have zip-tied the valves closed before with no ill effects, it basically just bypasses the heater core.
You can use a mityvac to test the functionallity of the heater valve, I think orielly's has them to borrow if you don't have one.

If you don't have vacuum in the cabin, check the lines where they pass through the firewall in the engine bay. I find those lines become disconnected all too often, causing the valve to quit working. If they are hooked up, that means you have a vacuum leak which is probably robbing you of a 1/10 hp!

Did you see the 87s parts car in vancouver on cl?

MB968

Not sure, live on E. Side up on Mt Tabor. Car is Midnight Blue Metallic which is a very dark blue that almost looks black under some conditions. I was at the PCA arrive and drive in June, and the autox in May.

MB968

Thought I'd add one other tidbit about heater valves. My '62 Triumph TR3 that I had many years ago, used a simple water valve on the rear of the engine just like you have for the garden hose. If you wanted heat, you popped the bonnet and opened the valve. Little too basic I suppose for modern day.

MAGK944

Blocking off the feed with zip-tie on the valve works, get it fixed correctly before winter. If you like to breathe and its cold outside you will miss the demister. If you can hold your breath for the entire journey you will be fine

16valver

Another Portlander!!! I wonder if I know/have see you before...? Yeah at this point I'm pretty sure there is a vacuum leak somewhere. I'm starting to really hate this whole system.

I did not see this parts car on CL. The last thing I need is another dead car in my driveway hahaha.

Yeah, unfortunately I missed both of those. I'll be sure to wave if I see ya!! I'm in NE, Hollywood district.

I really like this idea actually. Might have to look into it or something similar!!

Well its funny, I actually never use the heat in the winter. I'll use the blower for sure, but I usually go without heat. There are probably 3 days out of the year that I need heat. My car has very little interior so heat from the transmission, exhaust and engine usually creep in and warm the cabin.

This is why I've been toying with the idea of the block off plate. I would gladly get rid of the whole system all together and rig up some sort of fan system to de-mist. Thats a project for another time, though.

The more I think about it, the more I like the manual turn on/shut off idea. Lemme at em!!!

StickShift

I wonder whose car that was. I have seen it cruising down Division st a few times. I have the neglected blue S2 that you have probably passed many times.

Friend of mine has a red 968 cab and he just sold his black 968 coupe. He also has a 86 with a 968 engine. Very nice upgrade.

drift a 944

Are you sure it's the valve that's stuck? There is also a plastic clip under the dash which holds a metal arm, which often breaks. The arm closes the door between the heater core and the blower I believe. So when the clip breaks, the metal arm falls down opening the door, and causing constant heat. Fortunately, it is also one of those things you can just zip-tie back together to hold it. It is located under the drivers side dash toward the center console area (for lack of better descriptions). Won't hurt to check it anyway.

16valver

Hahaha man!! I've passed that S2 many times myself!! Love that thing. Never really know what it was before I knew about 944s but I've ogled it a few times now when I've buzzed up division. 968 Mirrors Love that color too. I'll have to blast by there more often haha.

Appreciate the input, you are sort of half right. Unfortunately I've been down this road before. The clips are fine and the flaps are shut, BUT I don't think the system is completely air tight anymore. I've verified that the heater valve is not getting vacuum, and because of that, remains wide open. Since hot air likes to rise/escape, it seems to find its way into the cabin and make my life miserable.

I suppose we should all be able to have the heat up and the fan off with no ill effects. I kind of like the cool breeze that the leaky flaps and joints let through when there is no flaming hot coolant running through the core. Thats why I want to cut off the line.

Just ordered up a manual control valve to try and throw in there so we'll see what happens.

StickShift

And just because I like creating problems for people,

http://portland.craigslist.org/mlt/cto/3896619031.html

900 bucks... You know you want it for parts...