Where to mount thermostat for AT cooler
 

Howdy,


I realize it's late in the evening for most forum members, but I'm planning on spending most of the night working on finishing up my transmission cooler install project. One thing that puzzles me is where I should mount the thermostat at. In the photos in the instructions, it appears to be mounted next to the heat shield for the exhaust manifold (and obviously not touching), but is also in an orientation I'm not entirely sure about as it prevents you from seeing the flow markings on the thermostat.


I've got some photos below, with descriptions, then I'll put forward the ideas I have on where this should be mounted. The mounting is via zip ties, so there's some flexibility.


https://i.imgur.com/qNY25fg.jpg


As you can see in this picture, which is in the same orientation basically as my view laying under the car, there's a space where it appears in the image in the instructions that the thermostat is mounted, but it looks like to do I'd have to zip tie to these two hard lines which would cause the thermostat to be oriented where you wouldn't be able to see the arrows on it's face, which doesn't seem to match the orientation in the instructions.


https://i.imgur.com/scLUQMc.jpg


Here's another view showing where the -6AN lines are coming in next to the radiator hose running to the water pump. You can see there's not a whole lot of space here where I could potentially zip tie the thermostat in place.


https://i.imgur.com/wJYhAOb.jpg


Here's what the thermostat looks like with the flow markers on it's face. Not counting the barbs, the unit is around 3"x3" and about 1" thick.




I'm tempted to just zip tie it to those two hard lines after cutting and attaching the hoses running from the oil cooler, then I can mount the remaining hose to the barbs for the other side and pass it through. If I do that though, it seems that the body of the thermostat makes contact with the crankcase, and I'm afraid this will cause damage to the thermostat or cause a racket under hard driving. If I try to zip tie it around the wider way, I'm afraid it'll turn under hard driving and maybe fall loose.




Any thoughts? I'm probably overthinking this, and if I don't see any replies I'll just give it a whirl with the best method I can come up with and hope for the best. I tend to overcomplicate things, but I'd rather put some thought into it now than have a catastrophic failure under hard driving later.

I test fit mounting it to the two hard lines (part of it pushes against the spring-type hose clamp that runs into the hard line). I'm not sure I like it, but this might work. It seems janky, because even cranking down all the way on both zip ties, it feels like it moves quite a lot.


Since I need to cut the lines to fit based on where I mount it, I'm kind of contemplating this before I continue. I'm curious if anyone else has any suggestions?


https://i.imgur.com/axnyec4.jpg


It doesn't touch the crankcase or exhaust manifold in this position at least.


https://i.imgur.com/VkhtzYf.jpg

Eh, I just decided to send it. Hoses are cut and I cranked down and cut the zip ties in the spot I posted previously. I'm hoping once all the hoses are clamped that it'll help hold it in place. With just two zip ties holding it, I'm afraid it'll vibrate/rub under load and I'm not sure how well zip ties will deal with the heat that may accumulate.


https://i.imgur.com/Ed8hCYV.jpg


I guess I'll know how successful I was soon enough.

Howdy,


I guess this thread seems a bit odd since nobody replied to me here, but thank you to the person who created the cooler kit for PMing me to help. I've finished plumbing the thermostat and mounting things in place, and am about to start the transmission drain/fill procedure (and praying for no leaks).


Just for posterity and if anyone else needs assistance in the future with the same thing, here's the last two photos.


https://i.imgur.com/OzfGb5O.jpg


Final thermostat plumbing and mounting position. I ended up cutting the original zip ties holding the thermostat to help with plumbing it on the transmission side, since it was a tight fit to get my hand through the hole near the steering rack. Then I zip tied it again afterwards. This also let me re-adjust it's position a bit where it had slipped on the original zip ties and really crank it down, so I feel a lot better about how secure it is now.


https://i.imgur.com/aaIor6M.jpg


The transmission return line off the factory heat exchanger into the thermostat was a bit longer than I wanted, so I trimmed it, but not quite as much as I should have. Fun story is that the hose ID fits the barbs so perfectly that it wasn't possible for me to remove the hose when I attempted it. Good because it means I likely won't have any leaks, but it meant I couldn't go for round 2 trimming things. So yep, measure twice, cut once, don't rely on being able to trim a little more.


In order to compensate, I routed it to make a bend radius in two places and then zip tied it to the other line running to the thermostat and then together to one of the coolant lines running into the heat exchanger. I was worried that without a spot to tie it in, that it would interfere with the steering rack and get torn. I'm reasonably certain that it's safe now.


All in all, this project so far was probably simpler than I gave it credit for and I just way overthought it. On the other hand, I'm glad I did, since I'm now much more confident in a successful outcome.

How diffucult / time consuming was this install? And I’d love to see any before / after temp logs/testing. I got an AT i may be interested in doing this later down the road.

Don't know that a lot have done this but WOW we now have a thread to direct anybody else asking the question to.
This Ladies and Gentlemen is a man that knows how to ask a question (even if he didn't get an answer).

I tend to be very slow and methodical in how I approach things, and I tend to overcomplicate/overthink things, because I've found that in most cases that it leads to me addressing problems before they happen. All that is to say, it took me quite a long time to do this but I don't think it would take much time for most people to do it since they'd probably just go for it rather than contemplating every move.


The actual cooler itself mounts into the fog light well behind the fog light on the passenger side and you remove the right side air deflector from behind the bumper, which allows airflow to the cooler and the ability to route the oil lines along the lower radiator cover alongside the base of the A/C condenser and then around the condenser, radiator, and fan shroud to exit near the water pump into the lower engine bay. From there, you can see in my photos above where the thermostat mounts with zip ties.


The most time consuming part was dealing with figuring out where to put the thermostat and the ^*%&ing hose clamp that goes on the factory hard line from the transmission that's up above, since it's a /very/ tight fit.


I'd advise if you don't already have these tools before starting to make sure to buy the following and save yourself the Uber trips I had to make:


* 24mm 1/2" drive shallow socket (for the transmission fill plug, yes it's really 24mm)
* 7mm ratcheting combination wrench (for the hose clamps in a tight space)
* 1/4" drive short wobble extension
* 7mm 1/4" drive low profile socket (for the hose clamps)
* A long 1/4" drive ratchet (I bought an 11" swivel head, worked great)
* A fluid transfer pump (mine doesn't 100% fit my bottles, but I'm making it work)
* A pair of AN hose cutters
* A set of aluminum AN wrenches (hose fitting is -6AN)



I used a snap-away utility knife and a hose clamp as a guide to cut the hose and cut against the heat shield of the exhaust manifold, so you can do that too, but hose cutters would have been great.


Anyway, if I had known before starting what I know now, I'd probably have been done much more quickly, but I spent a lot of time second-guessing.


Also, order the 3 transmission plug crush washers. They're supposed to be one time use. DON'T LOSE THEM. I ordered mine awhile ago, had to wait 2 weeks, and then picked them up at the dealership. I apparently lost them, because I can't find where the hell they ended up at. I'm going to flip the crush washers and hope everything is good/leak check.

Also, I had a few more PMs asking for help with the automatic transmission fluid change because I was skeptical as to whether the plug which looked like the fill plug was actually the fill plug, because 24mm really?


Anyway, if you google for videos of people working on a Lexus IS250, it's the same transmission. Nobody apparently bothers doing videos of work on automatic BRZ/86s, but there's lots of videos of people working on automatic Lexus cars and that's how I was able to verify.


Here's the pictures I used in my PM when I was verifying the plug location, and yes this is a plug. Picture is annotated 23mm, but it's actually a 24mm.


https://i.imgur.com/BHpKQgi.jpg
https://i.imgur.com/oM9IvDs.jpg

Nice work with the install. I'm glad I could help you out with the PM's we exchanged. Always better to ask questions and be methodical.

Thank you again for developing on this platform for the AT cars and your help in PMs. I know we're the odd ones out going on the track with AT, so I am very happy that there are folks like you developing parts :)

I'm running starks kit as well. What temps are you seeing during track use? I have a sensor going to my AIM MXS dash and I usually read around 180-190 once I get going.

I haven't added a sensor yet. That's probably my next move is adding an oil pressure sensor and a temp and pressure sensor for the transmission. I focused on getting some cooling in place first. I knew my engine oil was hot, so it stood to reason that the transmission was as well. I still need to do something with the diff (sensors + possibly cooling).

What are the ambient temps during this? And what temps are you seeing in daily driving?

The Ambient temps during that day must have been in the 90's with no clouds. Daily driving it normally I would see it warmed up to around the same temps. Been in a terrible hot spell in my area and temps are consistently 180-190