87 supra help im freezing

[supranerd1987]

i just bought an 87 supra n/t from an auction. it seems like no matter how high the heat is set there is no heat coming out. it just blows cold air. This sucks especialy when its 20 degrees out. Please help

[bgrieger]

Heater VSV. Located on the firewall on the passenger side, it regulates the hot coolant flow into the heater core. It is normally closed. The vacuum assist is a well known failure. One solution that will turn the heat on: take the vac line that comes from the manifold and normally plugs low down on the assembly and plug it directly on the top nipple of the VSV assembly (right angle steel nipple, bent 90 degrees to the passenger side, top dead centre of the cadmium plated metal bulb). Now you have heat....until you remove that hose of course. I run this way, and keep a golf tee in my glove box for teh warmer weather.

[Jeeves]

Good call Bgrieger.

[supranerd1987]

hey thanks alot

[supranerd1987]

i have been monitoring the car pretty close for about a week now and its running really cold. Do you think that it could be that my thermostat could be stuck open? Before i go crazy unhooking hoses i just want to make sure that if its an easy fix i rather go the easy route

[Jeeves]

Well, did the above suggestion not solve/help the problem? It could be the thermostat, but it's rare for them to stick open. It's really simple to replace (I can do mine in sub 10 mins) so it's not like you've lost a lot if you replace it either.

[RJL1987]

I have a 1987 Supra with the same problem. I can not get any heat out of the heater vents inside the car. I have changed the contol valve on the passenger side of the fire wall, It opens and closes fine. I have even tried bypassing the valve altogether. I have good flow of water into and out of the heater core. I have hot water flowing into and out of the heater core. I still get no heat out of the registers. Any one know what else to do to get heat?
Thanks RJL123

[TcmaBoy]

Have you checked the air ducting? If its leaky then your hot air maybe getting traded for cold beforet it reaches the vents.

[Jeeves]

Originally Posted by RJL1987

I have a 1987 Supra with the same problem. I can not get any heat out of the heater vents inside the car. I have changed the contol valve on the passenger side of the fire wall, It opens and closes fine. I have even tried bypassing the valve altogether. I have good flow of water into and out of the heater core. I have hot water flowing into and out of the heater core. I still get no heat out of the registers. Any one know what else to do to get heat?
Thanks RJL123

Honestly, that doesn't make much sense. If the fans are working (which I assume they are) If the heater core is hot, there isn't anything stopping you from getting air. My guess would be a clogged heater core. How did you test flow through the heater core? You might want to try removing the hoses and blasting some water through it with a garden hose.

[bgrieger]

actually, it's possible the electronic vent control servos are stuck...never seen it happen before, but perhaps a coin or other small object is wedges in there...when you press the control buttons for which vents blow, do you hear and notice anything?hate to remember what it would take to get it out and find out...

Bob

[Jeeves]

Originally Posted by bgrieger

actually, it's possible the electronic vent control servos are stuck...never seen it happen before, but perhaps a coin or other small object is wedges in there...when you press the control buttons for which vents blow, do you hear and notice anything?hate to remember what it would take to get it out and find out...

Bob

Ok, well, I was going in the realm of possible, that's a near impossible one... But yeah, that could be a possibility. With any likely hood, it's probably similiar to removing the heater core. I've done that once, and never EVER want to again.

[RJL1987]

Your are thinking along the same lines I am, the servos that open and close the doors or the doors are stuck for some reason or maybe the fins of the core are cloged with an accumalation of whatever over the years. The fan works fine, air conditioner works fine. I can hear doors moving when I change the temprature settings.

As for the heater core I have run water with hose through it and blowen air through it and get good flow from either. both the hose going in and the one coming out are hot. Temprature guage is at about one third so doubt thermostat is any problem.

This all started after I had the air condtioner worked on by a garage that went out of business. They had trouble getting it to blow cold air after putting a new compressor, dryer etc. and kept the car several days playing under the dash. I am affraid they just put a door that was not working into a fixed position and left it.

It looks like a major dash removal is in order.

Thanks for the input.
RJL1987

[Jeeves]

As for the heater core I have run water with hose through it and blowen air through it and get good flow from either. both the hose going in and the one coming out are hot. Temprature guage is at about one third so doubt thermostat is any problem.

Do you feel ANY change in air temp when you punch the controls all the way up to 85? As another thought, if you're getting good flow It shouldn't be, but my car always ran nearer the half way mark. Again, YMMV. If you want the step by step heater core removal instructions (for removing the dash) I've got 'em in a Word document.

[supranerd1987]

hey if you have it in a word doc that would be awesome if you could send it to me...
My email is quietthecrowd@hotmail.com thanks

[bgrieger]

Probably a 50 page booklet

In all honesty, it's the single most PITA and time consuming job I've ever had to do was getting all that crap out of there, and that was on a parts car where any and all interfering metal met Mr. Sawzall...

Bob