Subject: Air Flow Heater Problems
Model and Year: 1954 (and 1953?) Chevrolet Passenger Cars
Source: Zone Letter - Louisville, KY
Bulletin Number: Z0-22-34, Feb. 17th, 1954
TO CHEVROLET DEALERS:
We have had a few complaints from Chevrolet owners that the Air Flow Heater will not heat properly and in some instances on 1954 models, the temperature gauge runs into the red or "danger" zone of the temperature gauge.
The two reasons for these complaints are as follows:
1. A new thermostat known as the "Pellet type", Part Number 3130923 was included in the 1954 Air flow Heaters for passenger cars and some of these thermostats would stick open and allow cold water to flow through the heater.
To correct this complaint, replace the "Pellet type" 180 degree thermostat in the cooling system with the new 170 degree "Bellows type", Part Number 3124025. This new thermostat should be used when installing Air Flow Heaters on all 1954 passenger cars because the radiator cap has been changed from a four pound pressure cap to a seven pound pressure cap. The "Pellet type" thermostats can be returned for credit on an "L&MR" in regular manner by you.
2. When an Air flow Heater is installed on the 1954 passenger car and the heater package included the 180 degree "Bellows type" thermostat (which was for use on 1953 passenger cars with a four pound pressure radiator cap), it will give an incorrect temperature gauge reading which is caused by the seven pound pressure radiator cap which is used on 1954 passenger cars. Although the reading will be incorrect, the engine will operate at only 180 degrees and will not cause any harm to the engine; however, it may alarm the owner as he may think the car is overheating.
When installing passenger car Air Flow Heaters, check the type of thermostat in the heater package and be sure that the correct one is used. The 180 degree thermostat can be returned to the dealer stock in exchange for the 170 degree "Bellows type", Part Number 3124025.
We are passing this information on to you so that you can be guided accordingly.
Very truly yours,
Zone P&A Manager.
Article ID: 796
Created: August 3, 2014
Last Updated: August 6, 2014
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1953-1954-corvette-zone-letter-air-flow-heater-problems-796.html