i need help with a crankshaft adapter

keakar

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i have several motors with the 1" x 3" shaft size but i have a particular mower that is set up to require the bigger 1 1/8" x 4" shaft for the pulleys to fit and line up correctly for the pto and the drive pulley to fit

my question is, i have seen the shaft reducers that can convert it from 1" into 1 1/8" shaft but it is still going to be too short at 3" long, plus those adapters all use a key slot to lock them in place so how would the pulley work since the key is part of the pulley? im concerned the pulley indent for the key way may not be long enough to lock everything in place

so what are my options? since buying another motor is out of the question at this point
 
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Scrubcadet10

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What Briggs engine is it? What equipment is it powering?
 

keakar

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What Briggs engine is it? What equipment is it powering?
its a craftsman fs5500 listed as a 24hp engine with 1 1/8" shaft by 4 1/8" long but came with no engine in it at all but does have the 1 1/8" drive pulley and pto

i put a B&S 20hp twin in it with 1" shaft by 3 1/8" long and a 1" drive pulley and pto, which worked, but keeps throwing belts, so then i saw the pulleys werent lining up so that is when i looked closer at the specks and discovered the different sized shafts on the engines

if i use the 1" to 1 1/8" sleeve adapter will the pulley keys still grip in the slots enough to hold? i can add a 1" spacer for the correct pulley alignment but im mainly concerned with the pulley and pto key way holding fast and not being an issue
 

keakar

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ok then, since no one will say if it should or shouldnt work

im going to order the 1" to 1 1/8" sleeve adapter and 1"x 1" spacer to convert the crankshaft to use the correct pulleys for the mower and have them positioned properly
 

Bobcat84

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Did you get it figured out???I'm going through same situation with zero turn engine swap. Need 1"to 1 1/8" adapter but also need the 1" extension for shaft length for Hydro pulley and electric pto.
 
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