Author Topic: Calculating pulley size  (Read 489 times)


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Calculating pulley size
« on: April 27, 2019, 10:52:38 AM »
I need a pulley for the alternator to go with the one on the engine.
I can easily measure the overall diameters, but new pulleys seem to be described in terms of pitch circle diameter.
Is it OK to work with the overall diameter figures?
Then I can just ask for a pulley of the required overall size?
Or is there an important difference, so I need to calculate the PCD of the engine pulley, then order the appropriate alternator pulley also in PCD terms?
I'd need to find out the formula to convert overall to PCD diameters.


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Re: Calculating pulley size
« Reply #1 on: April 27, 2019, 11:39:20 AM »

I take the easy way out and just punch the numbers in here.

Worked fine for me.