Great write up and thank you. I am moving into the build up of my spare 2f engine, when did Toyota go to the thermostat housing using four bolts? And could one of those be used in place of where the two bolt one went?
FJ40 Thermostat Installation How To (2 Viewers)
- Thread starter Vae Victus
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Sorry Jaffy, not sure that one.
1911
chupacabra
With the FJ60, I'm pretty sure.
It will fit the engine block, but the angle of the hose spigot is different, so check to make sure it will clear your 40 radiator.
This is a great thread! I just ran across it AFTER I replaced my thermostat in my housing unit. I'm rebuilding my head so it is off the head for now.
I realized that I didn't put the thermostat at the 11-1 o'clock position as @Vae Victus said to do. I have no idea which direction it was facing.
How critical is this? Should I pull it back apart, adjust it and RTV again before I put it on the head? I would rather not since the RTV is all set now but I don't want trouble down the road.
I realized that I didn't put the thermostat at the 11-1 o'clock position as @Vae Victus said to do. I have no idea which direction it was facing.
How critical is this? Should I pull it back apart, adjust it and RTV again before I put it on the head? I would rather not since the RTV is all set now but I don't want trouble down the road.
middlecalf
SILVER Star
And is 12-o’clock position defined?
I assume 1200 is the front of the engine?
Hey all, what gasket sealant do you like for the thermostat housing, and how long do you let it cure before you start the truck up again? I've got some permatex high tack sealant (black, in the plastic jar with the brush mounted on the lid) and some versachem type 2. Neither says how long it needs to cure.
brian
SILVER Star
none, use the gasket.
I am using the gasket(s) (I'm replacing the lower and upper housings). I meant sealant, not maker. So... you are saying use the gasket without any sealant?
Thanks for taking the time to reply.
brian
SILVER Star
never-seize both sides of the gasket(so it doesnt stick to the housing)...the gaskets job is to seal.
That is not advice I have run into before.
Tons of opinions on this topic. I use this stuff a lot, I really like it. Holds stuff in place during assembly, which isnt so important for the thermostat, but I always feel better putting some on especially if there is corrosoin on the metal.
Glad I read this thread. I had a thin gasket and when positioning the housing, it had a gap, and I thought, that must be the rubber gasket on the top holding it up, and if I crank it down, it will seal. Then I removed the rubber top gasket and the housing still would not go all the way down. Used a permanent marker and drew a line around the diameter on the thermostat and when placing it in the top housing it showed where it was binding. Measured the hole and where it was touching on thermostat and hole was about 1.5mm smaller. Luckily I have a mill/drill in my garage, and set it up and bored the hole out a couple of mm bigger. Even if I had used a thicker gasket between the two halves of the thermostat housing, it could have damaged the thermostat. Fits perfect now with that bit of clearance and the top rubber gasket sits where it should. It was a genuine Toyota Thermostat as well, so beware.
Vae Victus
Posting more than I know
- Thread starter
- #54
Hmmm, what hole are you talking about? I cannot envision what you had to enlarge here.
Vae Victus
Posting more than I know
- Thread starter
- #55
I just got this question from @cartelcruiser via DM yesterday. He asked "what is the jiggle valve". My thermostat did not have a jiggle valve (j valve) on it, but below is a picture of one that does.
Here is a great thread on jiggle valves in 4Runners that sheds absolutely no light on the matter. No, seriously, it is like the argument about which toothpaste is best.
From the discussion at the above link, I don't think the orientation of a j valve is critical, but merely helpful to lower the temps a bit due to fluid dynamics and the job of the j valve.
It’s the hole in the top housing that lets the water through when thermostat opens. It is about 40mm dia and pressed part on top of thermostat was about 41mm. After machining it out a couple of mm thermostat fitted perfect and everything working ok.
Thus is the hole I’m talking about FJ40 Thermostat Installation How To
Will Van
GOLD Star
I'm hoping this crew can help me. I pulled my 2F to reseal it because a Welch fitting on the back of the motor was leaking. I was uber meticulous during reassembly because I didn't want any leaks. I reinstalled the motor and test-fired my Holley Sniper yesterday. Everything worked great, but the thermostat was leaking at the seam between the upper and lower thermostat housings and under the head of one of the bolts.
I disassembled the t-stat housing and cleaned up the surfaces with a brass brush. I assumed the leak was due to pitting in the aluminum housings, but both machined surfaces look decent with only light pitting. They had previously been sandblasted and powder-coated, so they were certainly clean on original assembly.
Any ideas to prevent this from leaking on reassembly? I had previously used a high-quality paper gasket that was supplied with my gasket kit. I do not recall the brand, but it was Made In Japan. I prepped the aluminum surfaces and both sides of the gasket with Gasgacinch and let it get tacky. Then installed.
The thermostat is not interfering with the housing (I can use a "thin" gasket per the instructions in the OP).
Would the thick rubber gasket fix my problem? Should I use some Permatex water pump silicone?
I disassembled the t-stat housing and cleaned up the surfaces with a brass brush. I assumed the leak was due to pitting in the aluminum housings, but both machined surfaces look decent with only light pitting. They had previously been sandblasted and powder-coated, so they were certainly clean on original assembly.
Any ideas to prevent this from leaking on reassembly? I had previously used a high-quality paper gasket that was supplied with my gasket kit. I do not recall the brand, but it was Made In Japan. I prepped the aluminum surfaces and both sides of the gasket with Gasgacinch and let it get tacky. Then installed.
The thermostat is not interfering with the housing (I can use a "thin" gasket per the instructions in the OP).
Would the thick rubber gasket fix my problem? Should I use some Permatex water pump silicone?
John McVicker
SILVER Star
By your description it should have worked just fine. Should not require Permatex in this application. Are you sure you had the bolts tight enough?
ps: use anti seize on those bolts.
ps: use anti seize on those bolts.