clutch fan or standard solid fan?

[2manybowties]

I have a 71 chevy pickup with a 350 in it. It has the old style solid fan will it stay cooler with a clutch fan on it?

[LSUMurse]

The clutch fan stops turning as it hits higher revolutions, that way your engine doesn't have to push it when there's already enough wind coming through the radiator. It's supposed to save on horsepower and fuel economy on the highway. I don't believe it will make the engine cooler.

[2manybowties]

Thank you I appreciate that.

[brown7373]

I think a clutch fan will move more air at low rpms which an A/C truck needs. Is your truck running hot? If the other cooling components are in good repair (radiator, water pump) and there is not an engine or transmission problem it shouldn't run hot. My 72 with factory air, clutch fan never gets halfway up the gauge, even in traffic with A/C on in south Florida.

[Stocker]

Clutch fan will definitely cool better than a fixed blade fan. Since it engages only as needed, it has much more aggressive blades (usually more blades and greater pitch angle) and will pull a lot more air when engaged than a fixed-blade. Plus you only have the fan roaring as it pulls air when necessary, and not robbing power & hurting fuel economy all the time.

[DreamRyder1963]

Is there a model of clutch fan that is recommended as a replacement for the fixed fan on our trucks.

[franken]

I'd check the diameter of the fan you have, or the shroud, go to the scrapyard and snag a solid blade (not flex) fan with 5 blades from an 88+ GM truck. That is if the diameter works. If not, troll cars.

Why? GM clutch fans were originally 7 blades and later changed to 5. I'm guessing GM figured out 7 was overkill.

Why no flex fan? In the words of a famous member here, "they will try to kill you."

[Lee H]

You can buy the correct fan for your truck on the classified board and a new clutch at your local DIY auto house. In order for it to work correctly and cool as designed you need the correct shroud.

[Tillik]

If you have a clutch fan and a fixed fan that have the same blades and diameter, why would a clutch fan cool better? Even at lower RPM's the fixed fan is continually spinning. I flushed my entire cooling system and upgraded to a 4 core to fix my overheating issue. So far so good but I've debated on finding a clutch fan if it works better.

[2manybowties]

I appreciate all the imput guys.

[leftybass209]

The solid fan is putting a load on the motor at all times vs a clutch fan which puts a load on the motor as the cooling system demands it. A solid fan in winter time can cause warm up issues.

[imjeff]

Your old style fan doesn't move as much air as a modern clutch fan set-up, but also doesn't take as much power to spin. It's also most likely located correctly in your shroud. The clutch fans move a lot more air and don't take power when you've got air moving through the radiator from velocity. They were designed for greater efficiency and fuel mileage, but unlike other efficiency add-ons, they work really well...as long as the fan is located correctly in the shroud. Neither will cause winter issues because your thermostat controls when water leaves the motor to be cooled.