Cooling Upgrade

When I got the truck it had the stock radiator. When I got the engine rebuilt the engine would over heat when idling for for an extended time like at a stop light when a fire truck caused the lights to cycle to be off on a hot summer day. No problem cooling while moving at speed. I checked around and could not find anyone in the area to re-core the radiator. So I bought an aluminum radiator from Summit Racing. Didn't fix the problem because there was no fan shroud and the fan was just "twirling in the wind". Parts manual shows that M15's didn't have a shroud. So I bought a six blade flex fan and a universal shroud.

Marking where to cut to clear the radiator support cross member

 Marking to cut the bottom grill plate

 I made radiator adapter members out of aluminum angle and tapped the radiator mounting holes for 5/16"-18

 Decided to just remove the entire support since it would be difficult to cut on the truck. The support is not structural anyway.

 Had to use a fan spacer because the new fan blade extended back to much and interfered with the belt and whatnot. Had to modify the spacer because the Stude water pump shaft had a larger non-standard pilot.

 Here are the old old Stude fan and the new fan. Not hub pilot hole different size.

  Fan installed with spacer

Marking in shroud for fan cutout

 Shroud cut

 Fitting fan ring

Fan and shroud installed. I have not yet installed the fan ring. May not unless I have a over heating problem. With ring installed it becomes very difficult to replace the fan belt on the side of the road...

Looks like the over heating problem solved. Let the truck idle for quite a while today in 95° weather.

Parts:
1 - AFCO Radiator, AFC-80147-S-NA-N (fits 38-46 GM Truck)
1 - Derale Flex Fan, DER-17015
1 - Summit Racing Fan Shroud,  SUM-380459
4 - 1"x1"x24" aluminum angle