MCI pulley diameter

[edroelle]

I was discussing engine cooling with an individual with an 8V92T.  When I repowered my MCI 8 with an 8V71T, I knew the pulley diameters, but they are vague to me now.  MCI had a few different upper pulley diameters to drive the cooling fans.  The smaller the diameter, the faster fan speed, the more air flow.  I had a 7 3/4" upper pulley.   The way I remember, early MCIs had 8" or above, while later 8V92s may be as low as 7 1/2".

Can a few of you measure the pulley diameter, at the outside of the belt, and the engine it is cooling.  (I realize that is not the actual diameter to use in speed calculations.)

Ed Roelle
Flint, MI

[Dallas]

Ed,

I just measured the 102C3 upper pulley on the bus I'm working on and it is 8 1/8". That's not saying that it is the original, but that is what it has.
Measurement was taken on the outer diameter of the pulley, since there is no belt yet.

IHTH,

Dallas

[JackConrad]

I just measured the OEM pulley on our MC-8. Looks like about 8 1/8" or 8 1/4".  Jack

[luvrbus]

one thing I do know is you can go too small for speeding the fans a 6 and 1/2 inch pulley on a MCI 8 I had cost me all new fans with a lot more parts.To this day I don't know who was the idiot me for listening or him for telling

[Ncbob]

You might wish to check Fred Hobe's web site...I know he's been supplying the smaller pulleys for years.

If the dimensions aren't there you might contact him. Fred doesn't write much but he sure does read the posts.

NCbob