I have a 1985 4runner and i am currently trying to fix the heater, it barely blows hot air and everyone has been saying that there is leaves and stuff that are prob in my ducts and around my heater core. Anyone have pics or specs for trying to fix this problem?Tips and suggestions would help alot.

 

Like i told you in your other thread, make sure the heater valve it working by moving the heater heat control from cold to hot, with the engine running and the heater set to the hot position see if the heater hoses going through the firewall to the heater core are hot, if they are then chances are good that your heater core is good. (you could back flush the heater core to clean it out if you wanted to, that way you would know if its plugged up or not) So if everything checks out, then all thats left is cleaning out the heater between the fan and heater core. if your 4Runner doesn`t have a/c it makes the job easier, if it has a/c then the block will be between the fan and a/c unit, there is no need to remove the a/c unit to clean things up.

 

Like myyota said you probably need to backflush your heater core

 

Also maybe you could check to see if the valve is even moving when you work the the controls from the inside. I had the cable snap on me so I just get under the hood and manually open or shut the valve depending on the season.If that isn't your problem then listen to these other guys. the backflush does wonders if your core isn't too far gone. good luck, joe

 

AND it works to its fullest potential when there is NO AIR BUBBLES in the coolant system. It should be a completely closed system.

As for leaves in the ducting, the BEST RESULTS come from removing the dash and hitting every part of the duct work... and the center structure for flaps and heater core lay behind the radio area.

Otherwise, the rest of the ducting OTHER than the heater core housing can be removed and cleaned using a philips screwdriver for the ductwork and a 12MM socket and extension for removing the fan motor.

The intake for the fan motor is the passenger side venting on the windshield cowl... where the wipers mount. You can remove the wiper arms and the cowl, and clean from there.

When you select FRESH on the controls, air is sucked from that cowl spot. However the cab must depressurize in order to accept this new air. Ever wonder what those black vents were behind the doors? Turn the heat on with doors closed, windows up, stand outside of the vehicle, and put your hand about an inch from that vent. You'll feel the cab air exiting from this vent. Its a pretty cool design! Gotta hand it to the Japanese... never seen a 1984 Chevy, Ford or Dodge do that

 

Hey Guys MY Heater Wont Even Turn On Any Body GoT ANy ideas WHy??

Wirring is corredt
Relays Work
JusT Fann Wont Turn On

 

Thats too bad mine just recently started blowing cool air out of only the passenger vent everything else is fine i get perfect heat everywhere else...just havnt figured it out yet. Maybe you should flush your cooling system and check the thermostat/heater core valve?

 

On my 85 truck the plastic bolt that holds the temperature and location levers together broke again. There was a tsb for it and I got the new one but it just broke. I am going to put a steel bolt with a lock nut instead.

 

There's a coil resistor that is basically the "brains" of the variable fan speed operation. They get damamged pretty easy, so I'd check those and make sure there even plugged in. There should be a 4 or 6 prong plug, right next to the blower motor, that is held in by two screws on opposite sides ofthat plug. Remove and inspect. The seperate resistor coils can not touch one another or be broken. In the words of a UK repair manual... "unit is non repairable. Discard and renew unit."

Also, the switch itself could be bad, or atleast very dirty. The controls leave the factory greased up for easy operation, and have a high tendency to collectdust and... ew... hair.

 

heater blower resistor and motor 411:
http://4crawler.com/4x4/CheapTricks/Blower.shtml

 

Mine broke today too, while I was doing the heater core. Since it was covered under a TSB, do you just go to the dealer and get the new part? Free? Never done a TSB item before, if you couldn't tell.

 

It was a few years ago. I may have had the tsb with me but I don't think it was free. Like $6. If you need me to search for the TSB ask me.
On this old stuff, I think a metal bolt would be more reliable.

 

I ended up putting a bolt in it anyway, and it feels very sturdy now. Thanks for the info though.