FJ60 Thermostat removal and replacement. Step by step with pictures.

[SmartyPants]

Ok guys I had some problems with my current setup as you can see here: https://forum.ih8mud.com/threads/problem-with-thermostat-or-super-efficient-cooling-system.778689/

I purchased OE T-stat, upper and lower gaskets. T-stat is 88C or 190F.

First off, I have been hitting the bolts which hold the upper half of the housing with PB Blaster a couple of times a week for a month.

I got all the parts together.

Then I began by putting a used ice cream pail under the cruiser so it could catch the spilled coolant as I take the hoses off.

and put down some absorbent to catch any that I might miss.

Next step, Remove the coolant hoses, just the ends that connect to the upper housing, we don't need to do more work than is needed.

This is where that pail comes in handy.

Next we see if those bolts holding the upper housing on will loosen. Thankfully mine came out very easily, no problems at all.

 

[SmartyPants]

Then after the bolts are out I wire wheeled them clean.

Then I got myself a large flat head screw driver and wedged it in between the top and bottom half of the housing in order to separate the two.

Here is what it looks like with the upper half off. Clean, which is good.

Then I wire wheeled the upper housing clean and took steel wool to the upper seal area where the upper rubber o ring goes. As you can see , the PO did this job once before and used plenty of gasket maker, which got into the housing and who knows if that caused a bad seal or not.

So I got this all cleaned up with a wire wheel and some steel wool.

 

[brian]

no need for caulk, the oem gasket works just fine.

 

[SmartyPants]

Then its time to clean up the seal area on the bottom housing, I used a scraper and a razor blade, but first I stuck a clean rag into the coolant area so that no debris would fall into the lower housing.

Then we just put some red RTV gasket material ( a small thin amount) on our prepped surface, drop the T-Stat into its home and put our top O ring on.

then I set the gasket on top, with the protusion of the gasket sitting in the forward passenger side of the housing.

Then a little bit of RTV on the upper housing sealing area, again just a small thin amount, we don't want RTV getting into the coolant and causing problems.

Then we get our bolts and spread a liberal amount of copper anti seize compound on them so in the future this job is easier. Wipe the excess compound off and install upper housing over the holes and line things up, I found that If I hooked all the coolant hoses up they held the upper housing in place perfectly for me to put the bolts in the holes.

 

[SmartyPants]

Once the housing is in place and the bolts are in the holes, I got all the bolts to where they just started to give resistance and then snugged them up, not really tight, maybe 10 ft/lbs at the most. I incrementally tightened them too, so that none of them got tightened all the way so that it went on nice and even.

Then I tightened all my hoses back on and poured my ice cream pail of coolant back into the radiator using a large funnel.

By squeezing the large hose coming from the driver side of the housing you can manually burp the system and if you overfill the funnel, the added pressure will suck the water into the system. I used all that was in the pail and about 30 ounces more of distilled water. Do not use tap water to mix with the coolant, the minerals in tap water will cause the coolant system to scale up, creating problems. Only use Distilled water, not bottled or tap.

You can see my old T-stat had blue RTV all over it, probably causing a leak in the system and improper function.

Then we check for leaks and do a 20 minute test run.
Here is the temp before test run:

 

[SmartyPants]

Check for leaks

after 15 minutes she was up to proper temp:

and check for leaks again:

Everything is now operating properly so then I went and cleaned everything up so that when the wife gets home she is a happy camper.

Time to go fishing:

Hope this helps anyone out there worried about this task, it was a 1 banana job I swear. Only needed a 12mm socket and extension and a flat head screwdriver for tools.

 

[Seth S]

Old post revive.

I just changed my thermostat and I got a new housing gasket but no upper. The old one came out with an upper but it was shot. I put it all together for now. Not sure what the lack of that upper o ring will cause. I drove around a bit and it was warmer but still not impressive. The old t stat was a motorad 82c vs the one I just put in which was an OEM 88C.

Guessing that without the upper gasket coolant can sneak around a bit more and thus cause more cooling. I will get a gasket when I can

 

[OSS]

Yes, without the upper round gasket, you essentially have no thermostat. The coolant flows right past it.

 

[Elbert]

I would go on and buy / obtain a set of bolts for the top water neck, since often times those #*$%# seem to be brittle. Good write up.

 

[Wisco60]

Once the housing is in place and the bolts are in the holes, I got all the bolts to where they just started to give resistance and then snugged them up, not really tight, maybe 10 ft/lbs at the most. I incrementally tightened them too, so that none of them got tightened all the way so that it went on nice and even.View attachment 906004
View attachment 906005
Then I tightened all my hoses back on and poured my ice cream pail of coolant back into the radiator using a large funnel.View attachment 906006
By squeezing the large hose coming from the driver side of the housing you can manually burp the system and if you overfill the funnel, the added pressure will suck the water into the system. I used all that was in the pail and about 30 ounces more of distilled water. Do not use tap water to mix with the coolant, the minerals in tap water will cause the coolant system to scale up, creating problems. Only use Distilled water, not bottled or tap.

You can see my old T-stat had blue RTV all over it, probably causing a leak in the system and improper function.
View attachment 906007

Then we check for leaks and do a 20 minute test run.
Here is the temp before test run:View attachment 906008

Happen to know what gauges you're running?

 

[micruz60]

Happen to know what gauges you're running?

Looks like they are Auto Meter Products Inc.
Auto gage

 

[DrRock]

Does anyone happen to have the Toyota part numbers for both of these gaskets?

Thanks in advance!

Cheers, James

 

[MTB Land Cruise]

Does anyone happen to have the Toyota part numbers for both of these gaskets?

Thanks in advance!

Cheers, James

FYI.......For 1989 FJ62, i Just purchased complete set with Thermostat
1634161030 GASKET, WATER OUTLET
9043043002 GASKET, THERMOSTAT

 

[DrRock]

FYI.......For 1989 FJ62, i Just purchased complete set with Thermostat
1634161030 GASKET, WATER OUTLET
9043043002 GASKET, THERMOSTAT

Thank you!

 

[JamesR]

Did you use the stock sending unit for the temp gauge or did you do something else so the temp gauge in the stock gauge cluster would work also?

 

[Eyeorg]

Thanks for the help!

I replaced my thermostat after reading this, and clearly the PO loved using RTV. There was no lower gasket at all, but this thing was GLUED on.

Bought all new parts from CruiserCorps

 

[Rustyj41]

Disgusting. My lower housing cracked on install. @orangefj45 saved me a few times. @ToyotaMatt has a stud kit to replace the four bolts. Well worth the couple bucks.

 

[Eyeorg]

I cleaned it up and it turned out OK after a fair amount of scrubbing. However not sure if I should fix those unused/broken vacuum nubs.

 

[ToyotaMatt]

Thanks for the help!

I replaced my thermostat after reading this, and clearly the PO loved using RTV. There was no lower gasket at all, but this thing was GLUED on.

Bought all new parts from CruiserCorps

View attachment 3574480View attachment 3574481View attachment 3574482

Disgusting. My lower housing cracked on install. @orangefj45 saved me a few times. @ToyotaMatt has a stud kit to replace the four bolts. Well worth the couple bucks.

I cleaned it up and it turned out OK after a fair amount of scrubbing. However not sure if I should fix those unused/broken vacuum nubs.

View attachment 3575322

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the oem toyota japan spec. parts studs and non-serrated flat nuts 8 pc kit is a neat and relevant choice idea here as well too ...

however , i had not begun to dig and dive deep into the whole stone age reasoning that more often then not 1 or more of the #4 mark head 2 of them 2 bolt housings / 4 of them 4 bolt housing M8 sandwich SEMS single spring washer only and

also the 2 the #5 mark head block face bolts often snapped too ?

when the m8 sandwich bolts brakes , that in now a 50/50 chance death sentence for the lower housing , due to many factors of being able to successfully remove all of the broke old bolt , and also retail and meet in there to be chased or re-tapped ,,,,,

the HELI COIL method is flawed here , and they always came out with a new bolt , of pulled out as your cinched the 4 sandwich bolts down ...

some times i got lucky here , very often not too ...

i tried every new TV Blue screen latest 1-800 # / SORRY NO COD's liquid Steel wonder stuff the Billi Mayes rambled on about way more they
my boy Vinny about his iconic and legionary SHAM -WOW !


the block face bolts are a bad design or nobody cared after toyota all at once ditched the JIS # mark head bolts grading system globally , this some how related to the Mysterious 007 2000GT Level Conspiracy Japanese Crime Syndicate not whisper on the whole translon from gold zinc plated hardware w / # mark heads , that transformed overnight to Silver Blue Zinc Bolts with no more easy to understand and way way kooler to collect like match box cars for a 15 year old boy who needed a high school guidance counselor approved work permit to do his home work , and then be glued the big new wonder 36" tall 36" wide microfiche readers .....


anytime one block face snapped upon you using all the right star patterns and full cans of deep-creep , WD-40 , Slick-50 Rust-Killer " yea-right "

the cause and effect of one side suddenly breaking free , and the one that did not = the one that did not 's Sand Cast Ear snapping off in your face then and there ...

heat from a torch made all above worse too .....


the below is the modern 2024 ( i discovered these in Japan , @ the Macmaster of Japan ..) .

the Plating on them is called Violet Blue Silver , this has the highest salt spray rating per the J.I.S .

as a by product , one heck of a BLING - Factor too ,,,,


i cant say i have ever snapped by hand 3/8 ratchet a #8 mark head any size spec. bolt ...

the #7 maybe 1 or 2 M6 ASCO / AISIN cross threaded by who knows hub dial bolts .... but that is a rare event in my toyota lifetime ....


below is my very very well R&D time spent answer ... to this Fred Flintstone Hot Dipped Galvanized , right now at your TOYOTA dealer today in 2024 ...
,

if i wanted HOME DEPOT hot-dipped Picnic Table Rated Bolts 91611-40825 & 91611-41025 , i would call my local 1-800-go-toyota ....

,

 

[ToyotaMatt]

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Updated NEW 8pc Thermostat Housing 's Bolts Kit-Form-Kit , Violet Blue Silver Zinc Plated Salt Spray Rating Thermostat Housing ALL JAPAN Spec. JIS DOUBLE SEMS BOLTS Hardware Mounting KIT F1.5 2F 3F CARB. 3FE 1972 -1990 FJ40 FJ60 FJ55 FJ43 FJ62 FJ80

Updated 8pc Thermostat Housing 's Bolts kit-form-Kit - Violet Blue Silver Zinc Plated - ( Highest Level Salt Spray Test...

vintageteqparts.com

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