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tucsonjwt · 12-04-2016, 07:00 PM

To check your choke:

1) Open the hood, remove the cover from the air cleaner.

2) Pump the accelerator a few times, then depress the accelerator all the way to the floor once and remove your foot from the accelerator.

3) Check under to hood to see if the choke valve (aka butterfly valve) in the carburetor is all the way closed. If is not all the way closed when the engine is cold then the choke needs adjusting to make it close all the way.

4) Start the truck. Check under the hood again. The choke valve should be opening as the engine warms up. (If it is below zero outside this can take quite a while.)

5) Once the engine is at normal operating temperature, the choke valve should be all the way open (completely vertical.)

NOTE: I am the only person posting here who has owned several GM carbureted vehicles with all kinds of chokes and never had one work properly
on a consistent basis. For that reason, I have installed a $12 manual choke conversion in all of those vehicles, including my current 83 C20 454. If you have a manual choke you will always know when your choke is open, closed, or partially open. The only time you will be concerned about the choke is if the manual cable works loose and stretches out, then you tighten the cable with the set screw on the bracket.

You may have more than choke trouble but that is the first place to start.

For heater problems, grab on to the heater hoses to make sure that they are warm when the engine is at normal operating temperature. If your heater core is leaking you should be able to pull the carpeting back on the passenger side floor and see coolant under or on the carpet. Also, you might have oily fog on the inside of the windshield. You might have a clogged heater core and no leak, which could block coolant flow.

I have always had adequate heat and blower force with the stock equipment. I live in the 115 degree+ desert heat and have never had more than a stock radiator on my two 454 engines. I have always had normal engine operating temperature with the stock set up. Fan, fan clutch, etc. have also been stock.

Post here your engine size and others here will tell you what temperature thermostat you should have.

12-04-2016, 07:00 PM	#2
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Cold blooded truck To check your choke: 1) Open the hood, remove the cover from the air cleaner. 2) Pump the accelerator a few times, then depress the accelerator all the way to the floor once and remove your foot from the accelerator. 3) Check under to hood to see if the choke valve (aka butterfly valve) in the carburetor is all the way closed. If is not all the way closed when the engine is cold then the choke needs adjusting to make it close all the way. 4) Start the truck. Check under the hood again. The choke valve should be opening as the engine warms up. (If it is below zero outside this can take quite a while.) 5) Once the engine is at normal operating temperature, the choke valve should be all the way open (completely vertical.) NOTE: I am the only person posting here who has owned several GM carbureted vehicles with all kinds of chokes and never had one work properly on a consistent basis. For that reason, I have installed a $12 manual choke conversion in all of those vehicles, including my current 83 C20 454. If you have a manual choke you will always know when your choke is open, closed, or partially open. The only time you will be concerned about the choke is if the manual cable works loose and stretches out, then you tighten the cable with the set screw on the bracket. You may have more than choke trouble but that is the first place to start. For heater problems, grab on to the heater hoses to make sure that they are warm when the engine is at normal operating temperature. If your heater core is leaking you should be able to pull the carpeting back on the passenger side floor and see coolant under or on the carpet. Also, you might have oily fog on the inside of the windshield. You might have a clogged heater core and no leak, which could block coolant flow. I have always had adequate heat and blower force with the stock equipment. I live in the 115 degree+ desert heat and have never had more than a stock radiator on my two 454 engines. I have always had normal engine operating temperature with the stock set up. Fan, fan clutch, etc. have also been stock. Post here your engine size and others here will tell you what temperature thermostat you should have.