Heater control issues. How hot?

[Zorrro]

Concerning my '87 4wd gl with no a/c:

 

I am on my way to the wreckers tomorrow to get a new heater push-button control as mine is physically broken. It was broken when I got the car. The "covers" are all missing and I just have small clear plastic buttons to push. After trial and error I have found what button does what. Since it's been cold, I don't get the heat I need. I'm used to driving an air cooled VW in the winter (scraping ice off the inside while driving!). So I really feel there actually is a heater problem here.

 

This is what it does:

 

The outside air vent (behind glove box) opens on every setting except vent. For it to close on vent, I have to hold the button while driving, the air is a good kind of warm then. On defrost, feet or mix the outside vent opens and when it's below 30f it just doesn't cut it (Chills!). I have unhooked the outside air vent motor and found without the fresh air it doesn't defrost worth a darn, so I hooked it back-up. The T-stat is new and does maintain 180 F, Core hoses are hot and correctly hooked up, the mixing linkage moves from one extreme to the other. This is the first water cooled car I've ever liked and it's real practical, but I expect more out of the heater. My wife gets to drive the nice newer cars and they will "Melt your face off!" if you let them. Even on the cold days! What's with the Soobie? How can I get the heater to crank? Thanks, Zorrro

 

[fredrogers]

I had a similar problem when I got my 87 gl wagon.

 

The biggest thing stopping my heat was the cable on the temp adjuster. It was broke behind the dash. Since I did not have a replacement in the works I just grabbed the cable end and pulled it up to full heat. The next thing was my restore pack, but that was not a big deal I just have full fan and off.

 

You may also want a 192 tstat. That extra 10 deg. can make a difference in cold weather. You could even hold on to the old one to swap in for the summer.

 

Also if you are still having problems keeping warm you can put some card board in front of the radiator, only block about half of it. This will decrease you engine cooling thus increase the temp of the heater core.

 

Hope this helps!

 

-=fred=-

[Subarian]

Two thoughts:

 

If you have to hold the button in to get it to work, I would say it's definitely bad. If it were just a vacuum line disconnected, it wouldn't work even when you hold it in.

 

Although the hoses to and from the heater core are warm, you still may not be getting good heat transfer. That can be caused by a couple of things, scale buildup inside the core or damage or debris on the heater core fins. I would backflush the core by putting a garden hose on the outlet side of the core, if it's not too cold where you are. Also check for airflow across the core.

 

You also might want to go with a hotter thermostat, like FredRogers said. Those newer cars your wife is driving probably have 195 degree thermostats, because of fuel economy and emissions controls.

[subiemech85]

this'll answer your question

[jeffast]

i wouldn't mess withtthe thermostat unless your sure i put a 195 in place of a 180 in my friends civic and all it did was make the temp gauge go way up then way down while you were driving it then a month or two later it blew a head gasket

[Zorrro]

OK! I picked up my new heater control pack at the wrecker today. $25.00 and it was already pulled! I see now (I had no button labels before) that "Max AC" is the only way you are going to close the outside air flap. Once I get that in, I plan on back flushing the core with a hose. It's around 10F, I hope I can find a dry hose? My heater hoses have a nifty fitting just for the garden hose. One of the treads I read mentioned using vinegar to flush the core with. I have some old "apple" flavored stuff I think I'll use. I do not think my fins are plugged or bent as I get very good air flow, just not much heat. Thanks, I'll keep you posted.

 

[Subarian]

You could backflush by reversing the heater hoses and running some radiator flush in it, but you'll need to drain and replace coolant after you've done that.

[Zorrro]

Hey guys/gals,

 

I thought I replied yesterday but didn't see this in the tread? This is what's going on so far:

 

I have flushed the heater core with vinegar and mouth pressure (Yuck!). I then flushed with water and mouth pressure until all vinegar was gone. It was too cold to get a hose de-iced and I didn't feel like defrosting one in the house. I re-hooked the heater core up, filled and burped the cooling system. I also replaced my broken controls, it is real nice to have buttons that work! I have put a few hundred miles on it and the heat is only slightly improved. Max A/C is the only way I get any "good" heat out of it. Driving is a back and forth effort of driving on max A/C (no outside air) and switching back to defrost when the window fogs and so on. I expect the heater to keep the cock-pit warm in defrost. Every other car seems to do this? At the moment I'm planning a day to dismantle the dash and replace the core (just because I'm there). During that process I will be looking for air leaks and damper problems. At the moment, all the 3 actuators work and seem to direct air where they are supposed to. The heater hoses are hot with one that I can squeeze and maintain a good poker face. The other is too hot to squeeze for very long. The engine temperature does not change when heater is on either. I would expect in this cool weather that the core would provide enough cooling to keep engine at 180F when at idle. It still warms up to cooling fan temp when heater on full and car at idle. As long as your driving a 3mph or so temp stays at 180F. I'm pretty sure the core is not rejecting as it should. Either because of internal scaling or bypassing air. If hoses were cold at the core and warm at the block I would expect a plugged core. If one hose was hot and the other cool I would expect low water flow. If one was hot and the other warm I would expect normal operation and mine both being hot I would expect poor heat transfer. Any input before I devote a day to dash dismantling would be helpful. Thanks, Zorrro

 

[TomRhere]

From your discription of the hose temps, I would say that the core itself is ok. It really sounds like you have an air flow issue to me. Not sure of where to look, but it really sounds like a flapper isn't moving, or you have some obstruction in the airstream. Pulling the blower motor would be the easiest an a good place to start though. Maybe pull the flex duct that's between the blower housing/heater box and see if you get good air flow there 1st.

As far as pulling the dash goes, the EA-82 dash is way easier than the EA-81's are. I've pulled both... Moosens has a write-up floating around on here on pulling the dash out of the EA-82 vehicles. The '86 Sedan I have sitting in the garage has a mouse nest sitting right on top of the heater box, could possibly have caused some issues there. There's also one in he fresh air intake under the wiper cowl on the driver side. Pesky little varmits anyways.....

 

FYI; A properly working heater system doesn't have enough cooling capacity to keep the engine at the "normal" area of the temp gauge, usually the half way mark, it will heat up enough to have the cooling fan come on. Yes, you can use the heater to help cool an over-heating engine, but it's not enough in itself to do a proper job alone.

[Zorrro]

Tom,

 

 

"There's also one in the fresh air intake under the wiper cowl on the driver side. Pesky little varmits anyways....."

 

 

Are you saying there is more outside air intakes than the one behind the dash? If so, I'm looking there! I have a mice problem too. We have a modern full size truck I don't drive, cause of the 11mpg deterent. Anyway the mice moved into that and shredded the insulation on the fire wall. Nuke em!!!!!!!

[TomRhere]

Well, I'm thinking that's a fresh-air intake on the DS. Haven't evicted the mouse nest yet to see what it is, but it's a factory hole in the floor of the area under the wiper cowl. The intake for the heater system should be on the PS of the cowl area. I'm reletively new to the EA-82's, having just picked up the Wagon, Sedan, and Xt6 this year, but I'm learning. Kinda helps to have one to tear apart to see how things relate.

I have the dash out of the Sedan, as I'm stripping it down for parts. I took pics of the backside of the dash, and of the heater system as it's mounted in the car. I could get a few more detailed pics of the heater control system, door actuators and such and send them to you in an email if you like. Could try to do that tonight or tomorrow. Let me know....