My son's Craftsman mower DLS 3500 hydrostat had a 20 HP B&S intek that throwed a rod through the block. I replaced it with a B&S 17.5 engine that I had. The deck belt pulleys are the same size. The transmission pulley on new motor is smaller than old pulley so the slack in belt won't turn transmission. The old pulley shaft is same diameter but has a shoulder part way down inside that won't allow it to go all the way on so I can't just swap pulleys. Any ideas? Do you measure the pulley size by outside diameter or inside? If I get a shorter drive belt so it turns the transmission, will it affect the hydrostat drive in anyway? Thanks in advance.
Double Pulley belt
- Thread starter AChrome
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StarTech
Lawn Royalty
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- Feb 19, 2020
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Yes the new drive pulley will affect the drive as it will turn the transaxle pulley slower. Basically you lose ground speed. One option is measure the old engine crankshaft PTO end (if it is the same diameter) and shorten the new crankshaft by the required amount. Or simply find the right double stack pulley assembly.
And v-pulleys are measure by the outside diameter.
And v-pulleys are measure by the outside diameter.