OK Guys,

I want to install an actual temperature gauge in my '68 Cutlass S Holiday Coupe. (350 with new aluminum intake and Holley 4bbl carb) I am worried it is running a little hot on hot days (80 F plus) since it was leaking coolant out of the radiator cap the other day. My question is... electronic or capillary tube? Is there an advantage to using the capillary tube style, or will an electronic sensor be just as accurate?

Full disclosure... I had to replace the radiator last summer with an aftermarket plastic/aluminum version when my original sprung a leak and they told me it wasn't worth repairing.

I have Factory A/C, so there is the "extra" radiator for that in front of the main engine radiator. I have already replaced the fan clutch.

Thanks!

 

I prefer the capillary style. Since you have an aluminum manifold, you probably have an extra port where you can run both the gauge and the idiot light. Do you think you may have over filled the radiator causing it to puke? There is a fill line on the engine side of the radiator where the trans cooling coil is located.

 

I'd go mechanical - simple install and would likely be just as accurate if not maybe a bit more so than electric.

 

The capillary tube of the mechanical temp gauge must be carefully handled. If you break it or badly kink it, the gauge is junk. Wiring an electric gauge is MUCH easier, especially for the less experienced. The mechanical gauge requires a hole in the firewall large enough for the sensor nut to pass through. An electric gauge only requires a wire through the firewall.

 

... But before doing all of that, re-read Eric's post and be sure you're not filling the radiator past the place that says —FILL LINE— .

- Eric

 

I may have over-filled the radiator as Eric mentions. Didn't think of that. I will check to be sure. I may still install the gauge anyway just for peace of mind. Thanks guys!