View Full Version : Wedge TR8 Temp. sending unit.

03-07-2008, 09:24 PM
I just purchased a TR8 and the temp. gauge doesn't work. I found a 2 pronged electrical sender screwed into the top of the thermostat housing, but all the pictures and books state that the temp. sending unit is the smaller single prongned unit that is screwed into the side of the front of the engine. I removed both and would like to know what each device does. I'd like to get the temp. guage to work, so I will know if the engine is running to hot. Any help will the appreciated.

03-07-2008, 09:36 PM
Here we go from memory. I might have this wrong. One on the drivers side top of radiator is high speed fan switch. One on top of the front of the manifoldwith two wires coming out is low speed fan switch. One on front of manifold next to thermostat housing with a single green wire running to the front is the temp gauge sender. Usually the connection gets corroded. Wiggle the wire and clean the terminals. Should be good to go. Works by sending power to the sender. As the sender gets hotter, it changes the resistance in the grounding of the sender to the engine block.

03-07-2008, 11:29 PM
Well Todd, if that is from memory that is impressive.

Mickey Richaud
03-08-2008, 09:36 AM

Yep, Todd nailed it.

Yours sounds like someone has altered the system and added a sending unit for the cooling fans to the 'stat housing. That's what I had to do.

Is yours a 4-barrel conversion? The Edelbrock manifold doesn't have the high-speed temp sensor tap that the stock manifold has, so one has to be added in order to retain high- and low-speed fan operation. There's a triangular boss on top of the manifold, similar to the stock one, but it's not tapped.

Do you have the low-speed sensor on the left side of the radiator?

At any rate, the temp sending unit is the single terminal sensor with the green wire that Todd mentioned.


Oh, and congrats on coming over to the dark side! Pictures? Thoughts?