reassembly of the A/C and heater / was alarming ATF puddle, heater questions and a cold day in NOVA and aircon ignorance (1 Viewer)

[John Young]

So I got of the plane from Dubai to Dulles a few hours ago. Badly jet lagged, but embarrassed that none of the 3 LC's I have in Northern Virginia is fully functional. The 98 is laid up with a bad front right axel shaft--lost in transit by UPS. The 2000 rusty ebay mistake--well the less said about that the better. And finally, the white Middle East 80 I got for my older boy has a non-functional heater--and it was -7 c here when I landed.

I took a nap and went out to have a look at the 93. I recalled that I had removed the control cable from the hot water valve at the center of the firewall last summer when I could not get it to move. I manually opened the valve (so it looks in-line) and warmed up the engine. No joy in terms of heat in the cabin. I tried all the various permutations on HVAC controls but no joy. I then looked here to see if I could find some kind of troubleshooting guide for the HVAC but I have not found that yet; next step is to spend some time with the FSM, but I suspect this won't be simple.

More alarming is that while I was waiting the 10 minutes or so for the block to warm up I noticed a pretty big puddle of ATF under the truck:

There was a drip every 3 seconds or so. As I mentioned, it was a very cold day and I was just idling the engine. I checked the ATF level and it seemed OK but I didn't have a rag with me.

Any of you boffins have any idea as to why suddenly I'd get an ATF drip like this in this location on a very cold day and what, specifically, I should do at this point?

And if any of you have any ideas on a quick fix to get heat working manually, that would be stellar. Hot water is flowing through that heater hose. Just nothing in the cabin.

Cheers!

 

[Jgrauman]

O ring on the tranny dipstick tube is cracked? About the right spot. For the heat, HVAC control problem, blend door problem, heater core flush

 

[Kernal]

Can you see where it is actually dripping from, off the bottom of the bellhousing, or the left side of the engine (auto transmission cooler lines?)

 

[BILT4ME]

Could be transmission lines or power steering.

Could be the back of the PS pump. They are know to blow out a plug in cold weather.

 

[ppc]

Does the rear heater work if so equipped?

 

[Kernal]

"Could be transmission lines or power steering."

Years ago my 1FZFE high pressure power steering line banjo bolt union was leaking, ATF from the power steering system was trickling and blowing back along the transmission cooler lines and dripping off the bellhousing. Found the source after washing everything off and watching for the leak to reappear. Another time I had a slight leak from one of the soft ATF cooler lines that run
along the side of the engine. Repositioned the hose clamp, no more leak.
FWIW

 

[John Young]

Thank, all of you, for the suggestions of where to look and what to do next. I and the boy are going to put it in the garage, get the electric heater going next to us and crawl under and see what we see--and it is very helpful to have some starting points!

 

[John Young]

Does the rear heater work if so equipped?

There is a rear HVAC outlet system in the roof behind the second row. No hot air comes out of there--but I think it may be for aircon only.

 

[ppc]

US spec models have a rear heater that sits under the front passenger seat and blows heat into the second row.

 

[John Young]

US spec models have a rear heater that sits under the front passenger seat and blows heat into the second row.

Thanks PPC. And thankfully our truck has no such rear heater to go wrong.

 

[John Young]

My son and I climbed under today and the leak seems to be from the front of the bell housing. Here are a couple of the better photos:

There also seems to be some leakage dripping down from the transfer case.

I'm thinking that perhaps the seals on the transmission have gone. I checked the level on the dipstick and it was mid-range. I'm tempted to just keep driving and keep a very close eye on the level of the ATF. What do you all think?

 

[John Young]

Well, I feel a bit dumb...maybe it is just the jet lag. Turns out that the entire heater core was bypassed sometime during its life in Dubai:

The coolant just goes from rear of the engine block through the heater valve (which was disconnected) straight to the water pump return. We stared and stared at these coolant loops but it was finally the FSM diagram that lead us to discover the obvious.

Now time to look for some hose...

 

[amgraham]

Hope the heater core isn't bad and that's why it was bypassed. I would definitely drive it a bit and see if the trans leak slows down, just keep an eye on the level. It's not unheard of for a front pump seal to start leaking after sitting around for awhile. Some conditioner probably wouldn't hurt either.

 

[Kernal]

Is the red fluid dripping off the bell housing red coolant or ATF?

Appears the fluid on the transfer case is blowing back from the transmission
but might want to check what fluid the previous owner put in there.

Your missing the plastic inspection cover from the bellhousing, obviously.

 

[John Young]

Well guys, my son and I got everything together, partly by going into the back of the local auto parts store and finding some heater hoses that had the bends we were looking for.

I let my son crawl up on the engine.

The heater worked to an extent, but yesterday I found a puddle of coolant in the passenger footwell, as some of you warned me might occur.

It is a slow leak and I'm going to try to figure out whether it is the core or just some of the piping; in either case it looks like it is time to pull the dash. Glad I am not depending on this as a daily driver!

 

[John Young]

Hi all,
I'm back in Virginia and likely to stay here for a while. My boy and I attempted to re-connect the heater core but discovered that the old core was toast. I posted a bit about that here in other threads. The dash is completely apart and I'm worried about remembering how to put it back together. And most importantly I know I need to take out the aircon to be able to remove the heater core to replace it. I'm just girding my loins to depressurize the coolant and actually do this thing. The label on the truck says R12:

I'm hoping y'all can offer some advice. I've never tried to do any aircon stuff ever before.

1. Is re-pressurizing the system something I can do myself? Do I just need to get one of those manifold gauge things from Amazon? I know I need to figure out what kind of valve is on there now to see if there is R12 or R134A in there now. The aircon was serviced a year ago in Dubai.

2. Should I replace the dryer even if I cap off the ends with aluminum tape right away?

3. Am I worrying too much about all this, and should just let some pro do it when I get the dash back together with the new heater core? Am I missing something major that I ought to be concerned with?

 

[John Young]

I should add that every day I go and look at the truck and try to see some way of taking out the heater core without depressurizing the aircon. I've even considered cutting up the plastic housing of the heater box. But each time I look at I I conclude there is just no way to do this other than removing the aircon box first. Why on earth did Mr Toyota do things this way?

When looking at the FSM they had a procedure for pulling the aircon box WITHOUT pulling the dash--basically you do it through taking off the glove box. But why did they make it so damn hard to change the heater core. It is entirely foreseeable that it will need to be replaced during the 25 year design life.

I can see the damn heater core. It just taunts me...

 

[rolliges]

Aircon is pretty straightforward once you understand how the system works. Depressurize, flush, replace receiver/dryer, expansion valve, o-rings, pull vacuum, repressurize. Autozone gauges rental, HF vacuum pump. This is minor compared to what else you may have.

Edit: wear eye protection when working with refrigerant under pressure.

 

[John Young]

Aircon is pretty straightforward once you understand how the system works. Depressurize, flush, replace receiver/dryer, expansion valve, o-rings, pull vacuum, repressurize. Autozone gauges rental, HF vacuum pump. This is minor compared to what else you may have.

Edit: wear eye protection when working with refrigerant under pressure.

Thanks RG. Good point re eye protection; had not considered that. And the idea of renting the manifold and vacuum from local auto parts place. I like that idea.

Are you able to tell what kind of refrigerant is in there from this photo by chance?

Does someone sell an entire kit for the o-rings and expansion valve? Do you have to replace the expansion valve each time?

 

[ZackR]

My son and I climbed under today and the leak seems to be from the front of the bell housing. Here are a couple of the better photos:
View attachment 2161467
View attachment 2161468
There also seems to be some leakage dripping down from the transfer case.
View attachment 2161469
I'm thinking that perhaps the seals on the transmission have gone. I checked the level on the dipstick and it was mid-range. I'm tempted to just keep driving and keep a very close eye on the level of the ATF. What do you all think?

Did you ever find out where this leak originated? I have one that looks just like it. My power steering high pressure hoses were replaced recently and I'm not losing fluid from the PS system. @BILT4ME - you mentioned a cracked dipstick O ring can cause this?