Dougryan
Bronze Member
Hi all,
I have the mower deck from a LB 30" rear engine rider that I plan to use as a tow behind mower.
It came with the spindle, blade, and pulley. It's an 8" diameter pulley with a 1/2" drive belt.
My plan is to power the deck with a repurposed pressure washer motor. B&S 875 series (6.5hp).
I need to take it all apart and measure, but I believe the motor has a 7/8" crank shaft with 2 keyways.
My question... How fast should the 30" spin? In other words, what size pulley should I get for the motor crank shaft?
I tried finding lawn boy part details to see the size of the stock drive pulley, but the mower is so old all of the parts are obsolete and I can't find the detail I'm looking for.
Thanks in advance,
Doug
Here is the pulley on the deck spindle.

I have the mower deck from a LB 30" rear engine rider that I plan to use as a tow behind mower.
It came with the spindle, blade, and pulley. It's an 8" diameter pulley with a 1/2" drive belt.
My plan is to power the deck with a repurposed pressure washer motor. B&S 875 series (6.5hp).
I need to take it all apart and measure, but I believe the motor has a 7/8" crank shaft with 2 keyways.
My question... How fast should the 30" spin? In other words, what size pulley should I get for the motor crank shaft?
I tried finding lawn boy part details to see the size of the stock drive pulley, but the mower is so old all of the parts are obsolete and I can't find the detail I'm looking for.
Thanks in advance,
Doug
Here is the pulley on the deck spindle.
