Need help identifying (sending units)??

[powthief19]

trying to get this whole thing out back together right the first time... any help is appreciated!

Rig is 77’ FJ40

I’m 99% sure the red topped sending unit is the water temperature sending unit and it goes in the front hole.

I have spare for some reason, I read that I should not put thread tape on this cause it could cause the sending unit not to get a proper ground.

Question: wouldn’t liquid sealant cause the same situation? Basically a barrier between the brass and the steel head?


Two other items I can’t come up with the right words to search effectively... what is the Black topped sending unit?

Last but not least, can anyone tell me which wires go to which sending unit?

Bonus points: where does the plug looking fitting go?!

 

[GA Architect]

Below is how ACC installed mine.

Your last photo is of your radiator drain plug?

 

[powthief19]

Below is how ACC installed mine.
View attachment 1599452

Your last photo is of your radiator drain plug?

Your picture makes have even more questions! Here’s a top view of what I have going on:

Looks like I have my heater line in the wrong hole?

View attachment 1599456

 

[ginmtb]

Here’s my setup on my 1.5F... used the paste on the temp sending unit but tape on the heater line. No problems.

 

[spotcruiser]

I'm using a marked-up photo from powthief19 above, since it shows all of the coolant ports.

My stock CA '78 has the heater connection in the aft hole (far right in the photo, #1), the black (or dark blue) temp sender in the hole just in front of the heater connection (middle hole in the photo, #2), and the red temp switch in the front hole (shown with the heater connection in the photo, #3). I bought the truck new and these are the original locations on my truck. I believe the black (or dark blue) sender is for the temp gauge and the red switch is for CA emissions (power valve circuit; continuity below 110F and open above 131F).

 

[brian]

the brass plug is for the block drain petcock.

 

[powthief19]

the brass plug is for the block drain petcock.

I’m not near my rig right now but is this what your referring to?

Neat and clean way to drain coolant from block - 2F

Should this plug go into a threaded hole as sort of discussed in the linked thread?

 

[powthief19]

I'm using a marked-up photo from powthief19 above, since it shows all of the coolant ports.

My stock CA '78 has the heater connection in the aft hole (far right in the photo, #1), the black (or dark blue) temp sender in the hole just in front of the heater connection (middle hole in the photo, #2), and the red temp switch in the front hole (shown with the heater connection in the photo, #3). I bought the truck new and these are the original locations on my truck. I believe the black (or dark blue) sender is for the temp gauge and the red switch is for CA emissions (power valve circuit; continuity below 110F and open above 131F).


View attachment 1599536

Thanks for the detailed response, looks like I’ve got some rearranging to do.

 

[powthief19]

Here’s my setup on my 1.5F... used the paste on the temp sending unit but tape on the heater line. No problems.

View attachment 1599474

Hey @ginmtb what do you have going on with that valve in the 90*?

 

[ginmtb]

Hey @ginmtb what do you have going on with that valve in the 90*?

It shuts off coolant so it doesn’t get inside at all. It’s amazing actually how much heat radiates from the hoses and the heater itself even without the heater on. That shuts flow to the inside completely. And I can verify it works - on my cross country leg through Yosemite it was getting pretty cold during the night drive and I turned on my heater and only got cold air blowing. I usually close it for the summer and forgot to reopen it for the cooler temps.

If you browse my build I posted the exact parts to use. Figure anything you can do to help with cooling the inside of these vehicles is worth it.

 

[powthief19]

It shuts off coolant so it doesn’t get inside at all. It’s amazing actually how much heat radiates from the hoses and the heater itself even without the heater on. That shuts flow to the inside completely. And I can verify it works - on my cross country leg through Yosemite it was getting pretty cold during the night drive and I turned on my heater and only got cold air blowing. I usually close it for the summer and forgot to reopen it for the cooler temps.

If you browse my build I posted the exact parts to use. Figure anything you can do to help with cooling the inside of these vehicles is worth it.

Thanks for the tip!

 

[GA Architect]

FYI - If your heater valve isn't working, click here > OEM Heater Valve < for the OEM shut off....or use @ginmtb approch.

Note, I have a new one I will install at my next coolant flush. But until then, once I see I don't need the heater anymore and shut off the OEM vlave for Summer, I get under the hood and give it an extra press to seal it shut.

 

[powthief19]

FYI - If your heater valve isn't working, click here > OEM Heater Valve < for the OEM shut off....or use @ginmtb approch.

Note, I have a new one I will install at my next coolant flush. But until then, once I see I don't need the heater anymore and shut off the OEM vlave for Summer, I get under the hood and give it an extra press to seal it shut.

So if this is working properly, GinMtb’s shutoff is redundant?

CityRacer makes it so easy to spend money... I had him send me one a while back and actually just installed it the other day.

 

[ginmtb]

I have a new one too guess I do have a redundant system lol.