Aq 120 B temp sensor question.

[Holy Shamolee]

I am tryinng to change the temp sensor. Somebody has obviously got there before me. The two part unit that is there is nothing like oem.
It has been stripped. I could probably stop the leak with a lot of pipe cement and teflon tape, but my sensor would not be grounded.
There is a plug near the back of the head. It looks like it could be the same size. Is it ok to use it for the sensor. If not any ideas on how to fix my problem..

 

[jerryjerry05]

If the plug on the back is in the cooling system?? Take it out and see if it's in the
water passage?
Or Home Depot and find the brass adaptor that can accept the sender and fit the newly tapped hole your going to put in?

 

[Scott Danforth]

got a pic?

if the hole is stripped, easy fix with a pipe tap and some fittings.

 

[Holy Shamolee]

So if I take tke back plug out and antifreeze flows out I can use it.? . If not, tap out the stripped hole to a bigger size and use an adapter to fit my sender?, Have I got that right?

 

[Holy Shamolee]

Not sure what size that plug is. 1/4 drive is too small and 3/8 drive is too big. The thread and size of the plug seems to be the same as the sensor. Best as my 65 yr old eyes can tell anyway.

 

[Holy Shamolee]

And man it is tight. I have tried to heat it a little bit but I am really scared to throw heat at my head. I take the little torch off the plug and it is almost instantly cool to the touch. Leading me to believe there is antifreeze behind it.

 

[Holy Shamolee]

I got the new sensor in. Had the same problem with temp reading high.
Ordered a new bosch gauge and sender kit from amazon for 30 bucks canadian. About 25 us dollars. I think I overpaid. Bosch might be a German name, but they must source real cheap stuff out of China.
Well, when it got here the threads just wouldnt fit. It came with 3 adapters, but none worked.
Went to the locat auto parts store and got a 3/8 npt tap. (35 friggin dollars canadian ) Tapped out the hole and put in the bosch sending unit and gauge
All is well now. Temp maxes out at 185 on the gauge and you can see that the thermostat open as it cools down.
Thankfully, no leaks.