Need engine temp sender and gauge for 1977 Chrysler 135

The engine head temp sender is missing and my understanding was that it hooked up to a buzzer originally and not a gauge. Can some one steer me to the correct parts so the sender matches up with a gauge that will give a temp read out and the proper size of the sender unit threads. I am not doing a water temp set up at this time.

Re: Need engine temp sender and gauge for 1977 Chrysler 135

The overheat indicator is either a buzzer or a 12 volt dash light--available at Radio Shack.

The sender is a misnomer: It is actually a switch that is normally open. When overheated, a bi-metal strip closes the switch and voltage goes to ground. The switch is a 1/4 - 20 screw with a 5/8 head and the bimetal glued to it. It can usually be either red or black. It screws into the head right next to the #2 sparkplug. If you need this switch, you can probably get it at franzmarine@aol.com.

Newer Force engines have the switch inside a well on the head and held by a rubber plug. You can NOT use this switch as there is no place on your engine to put it (unless you modify it by making a clamp to hold it to the head.)

NOW: If you want an actual temperature read-out, you can buy a sender and gauge. One type screws into the top of the head where the stainless slotted plug is. It is 1/8 NPT threaded. A second type is simply held tight against the head with a bracket and screw--simpler but not quite as responsive. Both these types come as a set --- sender and gauge.

The indicator buzzer is wired with one lead to the "I" or "A" terminal of the switch. the other lead attaches to the orange wire. While the ignition switch is in the run position, power is supplied to the buzzer or light. When the switch on the head grounds, power flows and the buzzer will sound or the light will glow.

Re: Need engine temp sender and gauge for 1977 Chrysler 135

Frank will this work, comes with the 1/8 NPT sender http://www.amazon.com/Sunpro-CP8211-StyleLine-Electrical-Temperature/dp/B000FJS4MW, or should I go with a "marinized" product?

Re: Need engine temp sender and gauge for 1977 Chrysler 135

That gauge will work, but you have to be aware. These motors run at about 130 - 140 degrees normally. I had a gauge just like the one on your link. The needle barely moved, even when the motor was at max temp. I found one that started out at 60? and maxed out at 200?. Much more accurate readings and easier to read.

Re: Need engine temp sender and gauge for 1977 Chrysler 135

Based on the reviews, I would not buy it. Two out of five claim it sticks and is inaccurate. 40% That's terrible odds unless you are in a casino.

When you do buy a guage and sender, be aware that you can not have both the temp gauge and the buzzer with factory wiring. Only one can be attached to the orange wire. If you want both, disconnect the purple wire from the voltage regulator and use it for the gauge and sender. Again, the gauge is attached to the "I" terminal of the ignition switch so it only has power when the engine is running.

Re: Need engine temp sender and gauge for 1977 Chrysler 135

ok, I will continue shopping. I am just going for the gauge, no buzzer. Will look for a 60 -200 degree sender/gauge, which I think Teleflex has, but doesn't seem easy to find "matched" guage/sender combo package, unless I am missing something.