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Posts Tagged ‘fan blade’

Fan Blade Trivia for Most 216 Engines

Thursday, November 16th, 2017

One of the most important factors in successful engine operation is to keep the water at far below the boiling temperature. This is best done by matching the radiator with the fan blade.

On 1939-53 Chevrolet trucks there was a change in cooling fans depending on the demands the truck might have. The following three fan blade assemblies were as follows:


15“ Diameter 4 Blades

Standard equipment on ½, ¾, and one ton. Matched with 3 core radiators.

Before Restoration

18” Diameter 4 Blades

Placed on most 1 ½ and 2 tons. Matched with 4 core radiators.

After Restoration


18” Diameter Heavy Duty 6 Blade – Optional


The Chevrolet Master Parts Catalog defines this fan “for use in low speed operations”. It was available on 1 ½ and 2 ton that would require slow moving or much of their RPM’s at idle speed.

Examples: A fire truck setting at idle speed while running the pumps to furnish water through their long hoses.

A flat bed farm truck during hot summer days. It slowly moves in a field while hay bales are loaded at almost idle speed.

No doubt at higher RPM’s this 6 blade fan would create extra wind noise under the hood but, after all, it was the price you paid to have a non-boiling radiator. (And it did the job successfully)


Overheating ½ or ¾ ton? As calcium builds up over the years in engine and radiator, heating problems may surface. As a “Band-Aid” to get by for a while, some owners install the larger 18” fan. With more air passing through the radiator core, major repairs can sometimes be postponed.

Fan Blade Change

Thursday, February 11th, 2010

At the beginning years of the 216 engine (1937-1938) the fan blade that cooled the radiator was made with a center hub plus four blades. Each blade was attached to the hub with three rivets.

This combination worked well when new, however, it was certainly more expensive to produce. A dangerous part of the design was the blades attached by rivets. Rain water while driving and sometimes a leaking radiator allowed dampness to get between the blades where they overlapped the center hub. As rust continued, the chance of a blade coming loose increased. Even with deterioration, the four blades stayed in balance while the vehicle was moving. Then all #*!# broke loose when a blade went through the hood, radiator, or where-ever!

A new design fan was introduced in 1939 and used through all the remaining 216 years and early 235 year, 1954. This blade was used on Chevrolet cars and pickup trucks. It is simply two identical blades welded together that held tight against the water pump with four fasteners. Much less expensive to produce and so much safer!!!

fan blade

Close-Up of 1937-1938 Fan Blade with Rivets.

fan blade

1937-1938 Fan Blade with rivets.

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Close-Up of the new improved safer 1939-1954 Fan Blade

fan blade

1939-1954 Fan Blade