Need 1965 C10 temperator sensor electrical help - need a parts guru

[markbritt]

Hello:

After a year and a half, my 1966 C10 stepside long bed is 99% done. Here is my problem. I have a 1971 Chevy 350 engine with 1980's heads on it. The 1965 water temperature sending unit will not fit in the heads as the hole in the 1980's 350 heads is too small. I picked up a 1980's "something or other" sending unit that does fit, but when the engine warms up, the gauge goes way over on the hot side (I have an autometer mechanical temp gauge and the engine is running fine). I have spent hours on the web trying to find a newer GM water temperature sending unit that will fit in my 350 heads (smaller hole) AND still allow the factory C10 gauge to work properly.

I believe there are two options:

1. Identify a water temp sending unit with the smaller threads that has the same electrical properties as the larger 1965 unit. (Anyone have an idea??_

2. Locate an adjustable resister that can be located in-line that would allow me do adjust the voltage on the current sender that is showing too hot.

Has anyone found a sending unit that will fit in my heads that will allow the gauge to function properly? If not, what about the adjustable resistor idea?

Any and all help will be greatly appreciated!!!

Here are pictures of the sending unit (1965 on the left, needed size on the right) and a picutre of the completed truck as well as the engine.

Thanks

[Nanook]

This link should help you out....

http://www.67-72chevytrucks.com/vboa...d.php?t=726700

[Macdaddy1]

If you have an autometer temp gauge I think you need to use their temp sending unit. It comes with different adapters to fit any motor. The frequency of the temp sending unit must match the frequency of your gauge.

[Nanook]

http://www.67-72chevytrucks.com/vboa...d.php?t=726700

This is the correct link

[markbritt]

Guys:

Point of clarification. The autometer is a mechanical gauge that I am using as a backup. I am looking to use, and have fully functional, the electric temp gauge that is in the speedo cluster.

Mark

[Nanook]

Check out the above posted link...I think that's what you need

[shp4man]

Nice truck! Like that color.
The difference between the later model senders and the old ones is about 14 ohms.
My truck has a 195 degree thermostat so used an infra-red heat gun, shot the top radiator inlet tube when the thermostat opened, put a potentiometer in the sender wire and adjusted the reading to middle of the gauge for 195 degrees.
I was going to get all fancy and put a 14 ohm resistor in there but other repairs/improvements take priority.
One guy at a car show called it "dial a temp"

[The Rocknrod]

If you had the original gauges this is the sender you would need: https://www.lectriclimited.com/elect...ing-unit-86912

[Captainfab]

That one won't correct the issue as it is 1/2" NPT. What the OP needs is a stock sender with 3/8" NPT threads. To my knowledge the only way to achieve that is to machine and thread a stock sender. The link that Nanook posted is to a thread started by member A1971Blazer, who does the machine work on stock sender for a very reasonable price.

Originally Posted by The Rocknrod

If you had the original gauges this is the sender you would need: https://www.lectriclimited.com/elect...ing-unit-86912

[Ken Cook]

Call John at RedlineG.com. If you send him the gauge and the sending unit he can make them work together.
I had him restored my cluster and he wanted the sender so he could calibrate the gauge to match it.

[Ken Cook]

Here is a photo of my cluster. He wanted the sender that I was using so he could calabrate the gauge to it. The gauges are all accurate now.
Notice that the amp gauge is now a volt gauge

[stsalvage]

I'm done this so fare 11 times here comes the 12th time.

The alt is on the wrong side your using the car Alt brackets.The 1960-66 had this problem i drove mine for 8 years and fixed the problem.Drove my truck for 16 years

Here is the plain simple was i can help with your alt problem and your heat sending unit problem.Never put it down by the exhaust the wire will last mabey 1 2 years then dry out and melt.

If your using the factory Brass and copper modien Radiator the none cross Flo.

In 1964 the Water out let came out straight and the alum Edalbrock intake Do not use the curve Water out let

Now in the exhaust manifold and brackets you need i will show you It will make your truck look better and work better

[stsalvage]

Now the sending unit The way i have it works its out of the way the wire sites right on the inner Valve cover.The hose for it i need to check the number.My way makes it look cleaner and its how the factory did it and you can even use the factory shroud

Plus if your using the small 283-327 water pump.You can use the fan clutch with the factory 18 inch 17-18 inch fan.I found throw auto Zone the extreme heavy duty 1975 454 Fan clutch will work with the 7 blade metal fan No more cooling issues.

Here is what it looks like on my 1965 3/4 ton

[stsalvage]

Another one to help you under stand what you need to do an have

[The Rocknrod]

What is that?