Heat blowing out from under dash/85qv

Mine leaks hot air more from around the steering wheel than under dash. It's the heat from the radiator not being fully sealed off or diverted.

 

My '83 leaks hot air under the drivers side dash. I think your right it is heat from the radiator.

There is foam insulation around the radiator and also around the air ducts and on the hood. I replaced most of the foam and it helps. It did not comp;etely resove the problem.

Check around the air ducts by the radiator. You may have a whole in the duct or the foam my have disentigrated.

 

Also, make sure the vents under the dash are closed.

 

There is sometimes confusion with the controls.

QV's have separate driver and passenger heater controls, but carb cars have only one, plus the choke control....make sure BOTH of your heater controls are off at the control AND the valves......

 

They're under the front boot hard plastic cover. Near where the heater box's are. One each side....on a RH drive car anyway..

 

Yes you will but the easiest way to see if you need to go to the trouble is to simply drive your car untill it's up to temp and just put your hand on the vents to check for hot air bleeding thru. I bet you will find that it is not, or VERY little. Not the amount that is causing the amount of heat that 308 owners know all to well.

On early H20 cooled VW's the heater control valve will begin to leak after several years. Even "fully closed" hot water sneaks by. They are cheap to replace. I am sure the Ferrari valve is not. (Although I have read that a Ford F150 pickup uses the same type) My advice -if yours are leaking- is to just disconnect them until winter. Pull off the appropriate hose and screw in a big bolt then use a hose clamp around that. Cheap, easy 100% effective.

 

I believe the real problem is the area below the spare tire well. I thought about it one afternoon when I had my driver's side wheel off to feed some wires thru. I noticed that there is no real barrier between our feet and that area. It appears that the radiator fan is blowing hot air right under the well onto the back of the footwell area. It (most of the time) is sealed off on the top part with the foam but not underneath. I plan on fabricating some sort of barrier below the rear most area of the spare tire well and the bottom of the car to see if this helps. I'll post my results when I'm done.

 

On my car, the heater cores have been removed for repair and the hoses are bypassed -- the heat still pours-in. It seems that when the radiator fan goes-on more heat comes-in. There must be a path like Dr. Cosgrove was refering to under the spare tire cover--we need to investigate this further with lots of posts!!
Mark

 

Mark,
There have been threads on this in the past...the heat appears to be coming from the radiator, not the heater cores. It seems to trickle in through various small openings being the dash...I have found a couple small holes that when driving at freeway speed, I could feel warm air flowing out of...so I plugged them with small plastic plugs I bought at Lowe's Hardware. There is still more heat coming from elsewhere, but I have not been able to trace it. One thing that helps a lot on most days, is to keep the lower vents open with ambient temperature air flowing through. That helps keep the warm air from building up under there....at least on a warm day with the top off, it is more bearable.

In other words, I am not getting any heat out of the vents, just ambient temp air...the heat is coming from behind and below the dash...and the radiator appears to be the source.

Dave

 

I to have this "heat" issue in my gt4.I've thought of removing the front belly pan and putting some insulation wool (the type you might find in the roof of your house)discretely in there to try and block any holes that there might be.I think im getting hot air through the steering column penetration.But were coming into winter down here in sydney and I might leave that project for the beginning of next summer.But please dont give up the quest!!

 

Thanks for the info.
In my car, with no heater cores, the heat does seem to be coming from the radiator and it seems to produce more heat at certain times. My thought is that more heat comes in when the radiator fans are on. Need to do some more experimentation--perhaps will try to drive with the bonnet cracked-open (but secured to prevent damage from a sudden stop).
If anything interesting is developed I'll post.

Mark

 

My car did this same thing.

It ended up being the rubber boot around the steering shaft @ the floor board. The hot air from the radiator just poured in the rather large hole.

I mounted the boot back into its place, and the heat stopped.

Hope your fix is that simple.