Looing at a 50 model GMC that has a 350 small block conversion. The engine sits low and the radiator is in the normal position so an electric fan system is needed. What cooling fan system works here? It has an 18 inch fan on the engine side, a puller, I guess, but that is not getting the job done here in Texas. What can I do to get some improved cooling on this situation? Thanks!
Is there any shroud or is the fan just mounted to the inside of the radiator?
Typically those fans are just attached to the back side of the radiator but they only pull air through the fan diamter, the rest of the radiator surface area only gets air movement from travel.
I made a sheet metal shroud to mount the fan approximately an inch away from the radiator surface so that the fan can pull air through the entire radiator surface area. I have not completed the build to know how it handles heat but our heat here in Wisconsin is nothing like you have in Texas either.
Last edited by Phak1; 09/13/202312:19 PM. Reason: Fixed photo attachment
I use a Spal 18 inch puller I bought from Old Air Products (in Ft Worth). I use it with their shroud made for the AD truck and it is the VA18-ap7/LL-594 fan. It is rated at 2023 cfm and if you have a decent radiator and the engine is clean it will keep things cool even at 110 degrees outside temperature. I use it with the thermostat control. As I recall it takes apx 20 amps. I have it on a Bosch style relay controlled by the adj thermostat. Won't be a problem on the 350 but with the 235 you'd need a short water pump.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
Also, if you get that Spal fan make certain it is the one made in Italy. There's a knock off made in another country where Chop Suey is a popular dish and you don't want that one. For sake of confusion, they use the same part number on the imitation.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
Did you have to relocate the radiator forward, the sb 350 water pump pulley is only about 2 inches from the original radiator mounting, looks like it could be moved forward enough to get more clearance for that fan & shroud.
How did you mount the engine/transmission? I am surprised that your 350 mechanical fan isn't close enough to the center of the radiator. I had no issue with the '49 and the '52 that I put 350 engines in. I did use serpentine belt setups from a junkyard. I had to choose the correct fan spacer to get my flex fan close enough to the radiator. Both of them run right at 180 degrees all day long. 190 with the A/C on in 90+ degree weather.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
The fan I used was an E-Bay special; 3000 cfm rated at 10 amps. I did not relocate the radiator forward but my engine location is as far back as I could make it and have cab clearance. I also used a short water pump to provide as much clearance as possible. You can determine if the engine has a short or long water pump by looking at the pump to timing chain cover clearance (short pump is very close).
Got the kit from the Old Air Products! with the SPAL fan and the fan shroud- and the adjustable temp switch set low, it seems to work just fine in this late Texas heat. Glas I asked!
