Blower motor not blowing

[Honey Badger]

Howdy all, this may be addressed in another thread but I looked around for awhile and didn't see it so here goes.

I've had my Tercel for almost 20 years and it's an absolute champion. 311k miles, going strong. I love driving it in the winter, gets around great, super fun for snowy parking lot drifting, etc...

Only issue is that the heater doesn't move enough air so I need to suit up in full mad bomber gear for winter driving.

This has been an issue for a few years and I've tried everything I can think of, replaced the blower motor, been all through the dash looking for critter nests in the ducts. With the blower motor going full bore, it sounds like it's getting plenty of juice (and I've tried running 12v straight from the battery) but barely pushes air through the vents, defroster or floor heat. No difference with fresh / recirc or hot / cold, across the board there just is just almost no air moving through the system. The air that does come out is nice and warm, I pulled the vent direction doober out so I can stick my hand right into the vent and that's nice. I've been dreaming of having air just blasting out of those vents for years, that would be a game changer, both summer and winter.

Any thoughts?

[BaileySims]

The box that contains your evaporator core is clogged with debris. If it hasn't been removed in 20 years, that's your best bet. I recently replaced mine and boy was it full of a ton of trash. No idea how it even got in there in the first place.

[Honey Badger]

Thanks Bailey. I don't have AC on mine, does it still have an evap core?

[BaileySims]

No ac like factory no ac? I'm not entirely sure on that. If that's the case then maybe the evaporator core container is empty and all the debris is stuck up against the heater core. Are there any issues with sliding the temp control left and right for the blend door to actuate?

I was having the same issue with my truck as well. Yanked out all of the ac stuff, cleaned and sealed the evap container and flused out the heater core. Works like an absolute dream.

I would pull out the evap container and have a look around inside there to the left and right. I'm sure that is where the issue will be.

[Honey Badger]

Ok, thanks. Yep, there's no evidence of AC anywhere, no compressor pump or bracket for it, no button on the temp control panel. I'll dig into the heater core next time I have a good day to work on it, until then I'll just drive the 4runner. One thing that's stumped me this whole time is that it doesn't move air when I'm bypassing the heater core, temp control lever moves fine and I can hear the flappers flapping. Will let you know what I find, might be a few months.

[ARCHINSTL]

I think - pardon me, if but I would hypothesize that member baileysims - has the answer.
I know that it worked for me.
Tom M.

[Petros]

if the tercel never had an ac, it has a completely different duct between the blower and the heater box. there would be no condenser in the duct because it would not fit. seems to me debris is the best guess, you might pull the cowl panel off (the body part between the hood and the windshield with the grill) and clean out the air inlet to make sure it is clear of leaves and other debris.

In addition, it is not that difficult to pull out the blower housing and the ducts under the dash. you remove the glove box and the support frame that it attaches to and access is easy. It comes out with three 10 mm bolts as I recall, using a 1/4" drive socket with a long extension makes removing it easy. With the duct between the blower and the heat box removed you can reach into the heater box to see if the heater core is plugged up with leaves and trash, and can clean it out if necessary.

Another thing that happens is the inside of the heater core gets coated with deposits from water. This would only matter if you are getting airflow through the ducts, but it comes out only luke warm, rather than hot air. this will occur if you use tap water from your household water, it is full of minerals and chemicals that will deposit on the inside of the heater core over time, and blocks a lot of the heat transfer. You can fix this by pulling off the hoses to the heater, flush it with water and than fill it with vinegar for 30-40 min, than flush it out (I like to put a hose on the outlet and run it into a clean bucket to see what I get out of it, usually whitish flakes). Usually that will restore heat. Note that if your heater core is corroded and marginally thin, the vinegar might eat through the thin walls, if that is the case stop leak would stop it, but it means your heater core was so thin it was going to fail soon anyway, and you need to replace it.

Replacing the heater core is a big job, you have to pull the whole dash apart to get the heater box out. I recently done that with mine since I have been enduring too many past winters with not enough heat output, and I installed another heater core.

[Honey Badger]

Thanks Petros and Archinstl, I'll follow up when I get around to tearing into it.

[ARCHINSTL]

Some more pertinent links:
viewtopic.php?t=2312
viewtopic.php?f=7&t=10496&hilit=vinegar
viewtopic.php?f=2&t=3859&p=28629&hilit=leaves#p28629
Long, but worth reading: viewtopic.php?f=4&t=11855&hilit=vinegar
Tom M.

[xirdneh]

is the motor running backwards?
I had one where the blowers plug had been cut off and wire blades installed
I had to swap the wires because motor was running backwards