Fan Clutch for 250 L6 fitment question

[longbed67]

oldblue1968chevy has a fan and clutch that came off of a long water pump for a SBC and I was wondering if anyone has or if it is possible to use this on the waterpump of the 250 L6 motor... if this doesnt fit is a fan clutch made that will fit. Thanks in advance!

[71gmcburb]

i used to have a 79 van with a 250 in it. had to replace the fan clutch and got it from my local parts house. that was a few years back tho

[68gmsee]

Just curious. Why do you want to go with clutch fan?

[longbed67]

I figured it didnt need to be pulling power from the engine during warm up, and would allow for faster warm up times... as well i figured it didnt need to be running while low load cruising on the highway... so i guess I just "figured".... maybe I dont need it ....

[68gmsee]

Here's what I know. I have a 350 fan clutch in the garage I bought on ebay couple years ago. I also have a water pump from my 68 GMC with a 250. The round mounting part of the pump is 2 1/4" in diameter and the round piece on the fan measures 2 1/2" in diameter. In other words the bolt holes do not align.

Here's what I don't know. Whether the one that oldblue68's fan is the same as mine and/or if your water pump mounting is the same as mine.

Now... as for power gain, my guess is it would be negligible if any. The fan is considerably heavier than the stock one on the engine so it probably would be neutral in power gain and if you have the long spacer like mine, maybe detrimental to the water pump bearing with the extra weight.

[longbed67]

You make a very good point about the bearing that I had not thought of, By the sounds of it you have the same pump as I do.... I think i need to use the KISS principle here and just leave it be... Thanks!

[NGN]

Did they make clutch fans for L6 250 in trucks 67-72 ?