The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - What is the "Normal" operating temperature?

blindbug · 09-03-2019, 05:15 PM

I just spent labor day weekend dealing with replacing a busted water pump. 350 with a stock (or at least a direct replacement) radiator, 50/50 coolant. We flushed the rusty coolant with the waterhose from both the radiator and the heater core. Replaced the upper, lower, and heater core hoses, replaced the 190 themostat with a 180 and replaced the water pump with a carquest brand. Drove the truck 3 hours in 90 degree weather and never cracked 190 the whole way, going 60+ (with a high speed of 79). Might have got near or slightly over 190 when I hit a half hour traffic jam due to a wreck. This, on a 1976 350, which MAY have been rebuilt at one point in its life (but not during my ownership). Sending unit is a Dakota Digital with DD gauge set, so should be fairly accurate.

Just some food for thought on the running temps in these old trucks.

09-03-2019, 05:15 PM	#20
blindbug Registered User Join Date: Oct 2017 Location: Louisville, KY Posts: 186	Re: What is the "Normal" operating temperature? I just spent labor day weekend dealing with replacing a busted water pump. 350 with a stock (or at least a direct replacement) radiator, 50/50 coolant. We flushed the rusty coolant with the waterhose from both the radiator and the heater core. Replaced the upper, lower, and heater core hoses, replaced the 190 themostat with a 180 and replaced the water pump with a carquest brand. Drove the truck 3 hours in 90 degree weather and never cracked 190 the whole way, going 60+ (with a high speed of 79). Might have got near or slightly over 190 when I hit a half hour traffic jam due to a wreck. This, on a 1976 350, which MAY have been rebuilt at one point in its life (but not during my ownership). Sending unit is a Dakota Digital with DD gauge set, so should be fairly accurate. Just some food for thought on the running temps in these old trucks.