Coolant Temperature Gauge - Needle position when engine is warm

[texas-topper]

Hi All,
First time poster to the forum and I am looking for a little info. Last weekend I bought a fairly clean, 1978 Chevy Big 10 with 53K original miles. It has the 350-4bbl engine. It seems to be running cool (better then the alternative) and I suspect the thermostat is stuck open.

Could you all tell me where the temperature gauge needle should be pointing when the engine is warmed up? I suspect it should be somewhat to the right of the long, center vertical tick mark on the gauge. Also, let me know what temperature thermostat your running. I believe GM installed 195ºF thermostats, but I am leaning towards putting in an 180ºF to deal with the central Texas heat.

Thanks for the help!

Ken

[Pyrotechnic]

The stock temperature gauge kind of scares me, especially the ones that just say C on one side and H on the other. The ones that say 100 and 260 arent as bad but you still don't know what the water temp is until it's pegged at 260.

I would go for an aftermarket gauge to at least supplement the stock one.

Running a 180 here in Austin.

[magwakeenercew2jh]

Originally Posted by Pyrotechnic

T

I would go for an aftermarket gauge to at least supplement the stock one.

Good idea. Any suggestions for a GOOD aftermarket one?

[Duro5341]

Mine sits around the 1/4 mark all the time. This is with a new rad, thermostat, heater core, and all hoses. So I would assume this is the proper location

Duro

[Hoods69BadBowTie]

I would say a 180* degrees thermostat should be good to run. I would also say to get an after market gauge so u will have a better reading.

[Pyrotechnic]

Autometer is good stuff. I recommend their Autogage line for the value. About the only difference I can tell between them and the Autometer stuff is less variety of models, and they are not valid for race contingency. I own a Oil Pressure, Volts, Water Temp, and Vacuum gauges as well a tachometer and they seem to be quality products. Of course if you have the extra bucks, the Autometer stuff is great and you got a wide selection of styles to choose from.

Here's the gauge pod that I have in my 77. The larger 2 5/8 gauges are really easy to read at a glance. I can snap a pic of the install if anyone is interested. http://www.autometer.com/cat_gaugede...gid=3362&sid=1

I'm also using oil pressure and water temp warning lights since the gauges are not mounted in the dash bezel and I wont always be looking at them. Eventually the plan is to remove the stock gauges and replace them with stock idiot lights and have these sending units trigger them. http://www.daymotorsports.com/product/282/c/C89/

[texas-topper]

Originally Posted by Duro5341

Mine sits around the 1/4 mark all the time. This is with a new rad, thermostat, heater core, and all hoses. So I would assume this is the proper location

Duro

Thanks for all the replies. Like Duro said in his post, my needle sets on the first tick mark(1/4 mark) from C. I plan to change the thermostat out and while I have the radiator drained I think I will replace the water pump as well. This truck still has the original water pump on it, which I think should be retired after nearly 30 years of service,...just to be safe. I think I also will borrow a pyrometer from work so I can see what the temperatures are at the radiator and the thermostat housing.

I agree that a good aftermarket temp gauge is in order. I used Autometer Sport Comp gauges on my '76 Monte Carlo restoration and really liked the look and quality of them. I will most likely put one on this truck as well. The current gauge is just as Pyrotechnic described "ones that just say C on one side and H on the other."


Thanks for the help!

Ken