Technical Fan clutch 71 chevelle

Hello I have a problem with a fan clutch from a 71 chevelle, I recently tried to replace it and the bolt pattern to the fan is different. It is very wide as the middle hole is 3 1/2 inches round. The fan clutch has a brand logo S . It has a number 032571SC stamped on the part where the four screws go to connect to water pump. Does any body know what this is? The fan has 3989095 stamped on it. The ones shown in the internet look exactly like mine but the bolt pattern is different it is smaller and the four screw pattern is smaller.

 

Pics of yours would help....

Also people change things out thru the years.. Might be from a different year car/truck

 

where did you get the replacement clutch? what part number is on the box it came in?

 

7 blade, shows as 1971 Chevelle,Malibu, SS & EL Camino all models including small block and big block models w heavy duty cooling or factory air conditioning
GM part No. 3989095 - FAN BLADE 19 1/2"DIA
April 71 Also 8CYL (MONTE CARLO)

Try a hayden/Murray 1705 or 2705

 

Seems to be a issue with that fan you are not the only one > https://www.chevelles.com/threads/need-to-find-correct-clutch-for-fan-part-3989095.965001/
It may be simpler and cheaper to replace them both.