Countryhick

??? is it possible i think mines plugged it gets hot for only a second while running then slows down the air again.

I think its plugged because it can be hot for a second while driving. even in the cold ass winter snow.

So anybody got an idea i had a stupid ciggarete fly at my yesterday.

Bushwhacker

Pull off both heater hoses from the firewall and hold a hosepipe over the heater pipes and blast any crud out with water. Do the same to the other heater pipe to make sure it's clear in both directions.

Could also be an air-lock in the cooling system.


Did you upset the cigarette?

Countryhick

I guess so it came out and hit me in the arm. Was wondering why though i dont smoke. lol.

And How do i look at the Air Lock??

can u give me a better description on where the heater lines are. ??

one2high

They are attached to the heater core where it comes out of the firewall!!

Bushwhacker

Had to 'borrow' this pic from Cebby, the V6 Runner is extremely rare over here.



Hope that helps.

okie81

Can you boil a heater core just like a radiator? That would be a lot of work

Getsome

I'm not sure how much work it is on Toyota to replace but I'd just replace it and be done with it. You can have all kinds of over heating issues with a clogged heater core and no heat in the cab. If you can get it out there is no reason not to replace it.

space-junk

iTrader: (1)

i wouldnt want to do it after my dad's let go on his 94 chevy half ton...
that was a major PITA to replace...
id do everything i could to unclog it versus replacing it... remember, its under your dash, and unless you take the seat out, its cramped to work on...

idanity

an acid bath is recomended.

when i replaced mine, (w/the A/C models, its a major pita...) it took a long ass time.
had to label a lot of stuff, as i know there are plugs in the dash that actually connect to different stuff (way behind the glove box, can be swapped w/a behind the dash__ so label those things)..

i have a used one, and it can be set into a acid bath at a regular radiator shop to get the mold out (it smelled funny)= not after i replaced it all, its a new truck smell again


here. (above) everything is still connected.
Below, its all out, and the heater core just slides into the black plastic box laying on its side in the very center by the sticks...(i should've beefed up the cross frame bar while i was in there)

iamsuperbleeder

I flushed mine out a few weekends ago.

It was doing the same thing; once the truck was warm, you could turn on the blower and it would blow semi-warm for a second, but after that there was no heat at all.

I thought the same thing; maybe the core's clogged. I've flushed a couple out in the past and it worked, so I figured I'd just give it a try.

The ideal way to flush it would be to "back-flush" it, or just run water through in the opposite direction water normally runs through it.

The coolant runs into the core through the hose the valve is attached to, and out of the other one.

1) Just unhook both hoses so that you juat have the two hoses sticking out of the fire wall still attached to the heater core.

2)Find something you can use to set up a good seal to a water hose and to the heater hose.

This here is exactly what I used; a peice from a radiator flush kit ( got it at Advance Auto for $2 IIRC )



Really, the only peices I used from the kit are these...



3) Take those peices from the kit, and set them up like so:



3) Turn the water on SLOWLY at first, just to make sure the core not solidly clogged up; if you turn it on full blast, you'll more than likely spring a leak in the core...

4) Slowly bring up the speed; I would only go about half the full speed the water flows.

If there's anything stuck in there, you'll see the crap come out of the other hose.

Run it till it's just clear water coming out, then put everything back together. Top off the coolant at the rad at the cap, and since you've just ran water completely through the core, there should be no need to go through the burp process; at least I didn't, and there's no air traped in my system that I'm aware of.

It took me all of 15 minutes, and now I have heat!


I wish I would have taken pictures, but it was cold, and I was more worried about getting it done, lol.


Hope that helps though, good luck buddy!

Matt16

I wonder if you could use some kind of drain cleaner, isn't usually the case that someone uses hard water to fill the rad and it deposits in the heater core? Drain cleaner might just work as long as it didn't eat the hoses or gaskets (which I really doubt it would).

YodaPala

You are wasting your time, buy a new one

idanity

it takes 30 minutes to backflush... ?


after what i went through (in the summertime, and planned for months) i would recomend the "hose- backflush" thing..it just may work perfectly.

i replaced mine b/c my truck smelled like wet dog...even after i removed the carpetting, panels and seats...all that was left was the dash and heading ...then that came out too.

it took a very long time, and theres a ton of bolts/ screws...and i had to buy a specialty tool (flex 10mm) to remove the entire dash (steel panel part)..

however, i would not recomend using "drain-o" or anything else that would seat in the heater and possibley eat holes in hoses or gaskets...

hope that helps

Tool Pants

I also suffer from a lack of heat. 1988 that I have owned since 1989. I dont remember the heater ever getting hot, but here in sunny California it is not a big deal. But I wish there was enough heat to defog the inside of the windshield on a cold morning.

I thought the heater core was plugged or the valve was not opening. I moved the heat control lever inside and could see the lever on the valve rotate all the way in both directions. So it is not the cable to the valve.

Then I thought the valve might be bad inside so that it only appeared to be working. I remove the valve. I could open and close the valve by hand. When it was open I could blow air through it. When it was closed I could not. Also ran water throught the valve with a garden hose. There is nothing wrong with the valve.



Then I back flushed the heater core. The water came out as fast as it went in. No junk came out. At first coolant came out then clean water. If you look closely at the picture you can see a good flow of clear water out of the heater core inlet at the firewall.



I did this during the summer. I was hard to tell if I fixed anything because it was so hot outside. Now that it is cold and my windshield fogs up in the morning - it still is not working. I slide the lever to full hot and the fan all the way up, and it takes forever to defog the windshield. I can drive for 2 hours and it will not even get warm. It is not cold, there is a little heat, but I would not even call it warm. A good flow of air blows out of all the vents - it just is not hot. When I switch to the windshield to the middle to the floor vents or the combinations, a good flow of air comes out of all the vents.

As for the history, this truck has always been cold blooded. If it is 100 outside and I am in stop and go traffic, the temp gauge sits just below the middle. 1 1/2 years ago I put in a SR5 cluster and the gauge is in the same position. So it is not my gauge. This truck has never over heated - I don't think it can. In 19 years I have never seen the gauge go past the middle. Weird truck.

The coolant level has always been up to the brim in the radiator and the overflow tank is also full. I have run the engine when it is hot with the cap off just in case there was any air in the system. When I removed the first hose from the valve to the heater core coolant came out. When I flushed the core a bunch of coolant came out. So I know coolant is getting into the core. Weird cold blooded truck - but it has always been that way.

Bushwhacker

Check the flap that covers the heater core housing under the dash, the flap that shuts off the hot airflow, is opening properly. It's probably stuck or the cable is kinked.

Tool Pants

I dont think there is a flap for the hot air flow. I think that is what the valve in the engine compartment is for, and the reason for the lever with the blue and red indicator under it. When I slide that lever back and forth all it does it to open and close the the hot water valve in the engine compartment.

When I move the lever with all the vent icons I hear flaps moving. But those are flaps to direct the air flow to different parts of the vehicle.

iamsuperbleeder

no, there is most definately a flap; you can hear it "flap", or at least I can, when you slide the temp control from cool for warm relitively quickly

couldn't tell yah where it is, but if you pull the dash apart and look at the back of the temp control unit, you'll see 2 cables coming from it; one go's to the heater valve, the other go's to that flap

Tool Pants

I know what a mechanical flap that opens and closes sounds like.

No flap noise when I slide the lever for the heater, only the valve in the engine compartment moves.

You people are telling me that there are 2 cables that are supposed to move with that lever. 1988 pickup with no air con.

I hate working under a dash. But I will look for a second cable.

Bushwhacker

Just remove the glove compartment section and you should be able to see where the operating cable goes.

iamsuperbleeder

this is not my pic; as a matter of fact, I just scrounged it up on eBay...



It's the bottom of the climate control assymbely. Looking at it from this angle, the top right slider is the one that changes between hot and cold.

Take a look at the two (2) cables running off of it



The one for the flap could be broken, or just disconnected, although I couldn't tell you which one of those two it is...

Hope that helps