Water temp sensor in block

[Aircooled1]

77 fj40 with orig 2f. I’m putting another water temp sensor in place of water drain on side of block anticipating Holley sniper setup will need another water temp sensor. I’ve torqued it moderately but I’m unsure if there is an actual torque value for this location. Also does it need any type of sealant applied to threads? Thanks in advance

 

[spotcruiser]

Some sealant never hurts. It's a pipe thread, so excessive tightening usually isn't required. Isn't there a second temp sensor location on top of the head next to the other temp sender? It seems like that would be a little more convenient.

 

[DangerNoodle]

I've always used some form of sealant as insurance. I like Loctite 545 for water and oil jackets.

 

[Aircooled1]

Some sealant never hurts. It's a pipe thread, so excessive tightening usually isn't required. Isn't there a second temp sensor location on top of the head next to the other temp sender? It seems like that would be a little more convenient.

I had that drain out anyway so I figured would use it. What kind of sealer is best for this application . I’ve always just used them for draining and never taken these out before . Thanks .

 

[Aircooled1]

I've always used some form of sealant as insurance. I like Loctite 545 for water and oil jackets.

Thx!

 

[rkymtnflyfisher]

Aren't there 2 ports on top of the head?

 

[zerotreedelta]

There are - that's how I ran mine (both in the head). The second is typically for the emissions controller, so it's moot once the Sniper goes on.

 

[rkymtnflyfisher]

There are - that's how I ran mine (both in the head). The second is typically for the emissions controller, so it's moot once the Sniper goes on.

That's how my extra gauge is plumbed into the engine, albeit it's an 83 2F from a 60 series.

 

[ToyotaMatt]

77 fj40 with orig 2f. I’m putting another water temp sensor in place of water drain on side of block anticipating Holley sniper setup will need another water temp sensor. I’ve torqued it moderately but I’m unsure if there is an actual torque value for this location. Also does it need any type of sealant applied to threads? Thanks in advance

View attachment 2807356

you are installing this sensor incorrectly .....fyi


- You can NO longer drain and service your cooling system propperly ?


- HEAT RISES , so the top of cylinder head is hooter then bottom , this is basic fundamental Physics .........


- who and why told you to use a drain port at lower end of engine ?


all above folks suggest using your extra threaded port on cylinder head , thats correct , this is dead wrong .........



all u need is this :

LINK below ...........

OEM TOYOTA Cylinder Head Coolant Temperature Sensor UNION Nut 90404 Fits ALL F & 2F Engines 1/75 -1987 FJ40, FJ55, FJ60 - VintageTEqParts.com

OEM TOYOTA Cylinder Head Coolant Temperature Sensor UNION Nut - 90404 - Factory Pre-Lubed w/ Lochtite Type Green sealer - ...

vintageteqparts.com

​

 

[Aircooled1]

Thanks for the info. That temp sender union looks perfect. But I’m not sure that my 9/77 FJ40 has an additional port on the top. Other than the head bolts, there does not seem to be anywhere else to put it. WIll attach a pic of my head and appreciate input if anyone can help me determine if I’ve got room for another sensor in the head. I do agree it would be more convenient and nice to keep the drain in place instead of sensor on the side of the block.

 

[sogncab]

It's right next to the other sender I believe.

I like Teflon tape for pipe thread. Easy to remove when the time comes.

 

[Aircooled1]

It's right next to the other sender I believe.

I like Teflon tape for pipe thread. Easy to remove when the time comes.

OK. I thought that was a head bolt just to the left of my existing sensor. I guess I can take it out and if theres a coolant channel I’m good to go. And if not, retorque to 95 ft lbs or whatever head bolts require.

 

[ToyotaMatt]

Thanks for the info. That temp sender union looks perfect. But I’m not sure that my 9/77 FJ40 has an additional port on the top. Other than the head bolts, there does not seem to be anywhere else to put it. WIll attach a pic of my head and appreciate input if anyone can help me determine if I’ve got room for another sensor in the head. I do agree it would be more convenient and nice to keep the drain in place instead of sensor on the side of the block.

View attachment 2808521

PM me or post close up of the back corner of cylinder head

i will make a concrete fact based ID for u

i specialize in this topic


i also have NEW OEM toyota Coolant sender sensors too ..fyi

 

[Steamer]

OK. I thought that was a head bolt just to the left of my existing sensor. I guess I can take it out and if theres a coolant channel I’m good to go. And if not, retorque to 95 ft lbs or whatever head bolts require.

Take a pic. We can most likely identify it for you and save you the trouble of loosening a head bolt.

 

[ToyotaMatt]

OK. I thought that was a head bolt just to the left of my existing sensor. I guess I can take it out and if theres a coolant channel I’m good to go. And if not, retorque to 95 ft lbs or whatever head bolts require.

H # LL no your not taking out a head bolt !


Settle down and post a tech photo

u pull-a head bolt your new head gasket WILL fail sooner rather then later ...

 

[Aircooled1]

H # LL no your not taking out a head bolt !


Settle down and post a tech photo

u pull-a head bolt your new head gasket WILL fail sooner rather then later ...

Good. Will get pic of the area now. Thx.

 

[Aircooled1]

Here’s some pics. Thanks for the advice.

 

[zerotreedelta]

Would be just to the rear of that freeze plug... I'm on mobile, but I'm not seeing it. Non-US spec rig by chance?

 

[Aircooled1]

Would be just to the rear of that freeze plug... I'm on mobile, but I'm not seeing it. Non-US spec rig by chance?

View attachment 2808563

USA FJ40 9/77 production

 

[Steamer]

Looks like you've only got the two and don't have this one.