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Discussion Starter #1
Still having trouble fastening front stack pulley to motor shaft.
There are NO setscrews anywhere on the pulley body. It apparently secures with a bolt/washer assy which screws through the bottom of the pulley into the motor shaft. Only problem is that there is a 6 inch gap from the bottom of the pulley to the bottom of the motor shaft, and the longest 7/16 bolt with a 20 pitch I've been able to find is 6 inches long. I need one at least 8 inches long to reach the motor shaft and secure the pulley. Any suggestions on where to find a long enough bolt, or any alternate fastening suggestions?
Motor is a 18.5 Briggs L Twin, model 42A707, series 1236-01. Thanks for any and all help - I'm beating my head against the wall....:praying:
 

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I think if you look harder you'll be able to find a suitable bolt..forget the "box" stores,go to a REAL hardware store or a good auto parts store,one like NAPA will likely have a bolt that size..if nothing else,a leaf spring center bolt can be had that long with 7/16"x 20 thead,the trouble with those is they usually only have a slotted head,not a hex head..if you have an industrial supply house in your area you should be able to get a bolt that size..

Another alternative is to use 7/16"x20 threaded rod,but you'll need to locktite it into the crank threads and tighten it securely by using two nust to "double-nut" it so you can tighten it up good in the crank first,then remove the two nuts and install the flat washer and lock washer,I'd use a nylock nut on the pulley end too..then cut the excess off..

But something seems "wrong" here-I dont recall ever seeing a bolt come out of a stack pulley THAT long!..most of those pulleys are "stepped" and the bolt goes way up inside ,not all the way to the bottom,most of the bolts I have removed aren't more than 1-1/2" long or so!..I think perhaps your overlooking this??..
 

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Discussion Starter #3
TractorHolic,
Thanks for the good advice - I hadn't even thought of trying NAPA or one of the other auto parts places.
The stack pulley is almost completely smooth inside, except for one "dimpled" area near the top which goes into the keyway on the engine shaft.
From what I can tell by looking at online diagrams, it appears to be an MTD pulley used on B&S engines. It came off of a 16 HP Briggs which was on the mower when I acquired it. My BIL replaced that motor with a 18.5 HP Briggs, using the hardware that mounted the 16 HP. He did say that there was/is a free floating brass bushing between the top of the pulley tube and the lower oil seal.
I will check with an auto parts store tomorrow.:praying:
Thanks again for the help - I'll let you know what develops....
 

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sounds like you need a different stack puley,where the crank goes in the pulley farther,therefor needing a shorter bolt.if any shops around there are like mine they will have several of those pulleys laying around.good luck,john
 
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