Mike 0 Posted November 4, 2007 Can anyone tell me how to know what size shafts are on briggs vertical motors from model, type and code numbers? I've tried the briggs site with not much luck although I do have the crankshaft numbers. i'm trying to determine if the shafts on 2 different motors are the same before removing them. 12.5 twin crank #393382 12.5 single crank #693653 As always thanks for any help, Mike Share this post Link to post Share on other sites
MarksA-C 93 Posted November 4, 2007 I think they should be the same, im not positive... Share this post Link to post Share on other sites
andrewk 0 Posted November 4, 2007 I'd need the type before I could look it up... Share this post Link to post Share on other sites
Dark 0 Posted November 4, 2007 all lawn tractors have the same out put shaft diameter riders use a different size and engines from power equipment Ie. generators, tillers water slurry pumps and etc.. if the shaft you are trying to use is the same length and width (usually 1" for lawn tractors)you can pretty much bet it will work. Lawn tractors run a standard 1" output shaft that is why you can use Kohler, Briggs and Tuchumsa for re-power and use the same pulleys Share this post Link to post Share on other sites
Al 6 Posted November 4, 2007 Hi, Some of the Sears tractors use crankshafts that are 1" near the main bearing and 7/8" near the end. These units use a special pulley that is stepped. Before you count on using a Sears engine, determine what crankshaft it has. Briggs has a crankshaft spec book. Mine is not really current and I don't know if it is available on line or not. I do have the latest Kohler crank spec books though. Al Eden Share this post Link to post Share on other sites
Mike 0 Posted November 5, 2007 Thanks Guys, I am actually committing a bit of blasphemy, I want to put a 12.5 briggs froma simplicity into a bolens. The bolens had this odd 12.5 twin in it, and I have a perfect 12.5 single from a regent with a blown hydro. Just want to make sure it will work before I take them both out. The bolens has an electric pto clutch on the bottom of the engine pulley. The engine numbers are below, thanks again guys! 12.5 twin mod 404707 type 011701 code 86111312 12.5 single mod 289707 type 011301 code9306104D Share this post Link to post Share on other sites
Mike 0 Posted November 5, 2007 Briggs customer service came thru......... Crankshaft # 393382 is tapped at 7/16-20, has a 1/4" Keyway, is 1" in diameter and 3-11/64" in length. Crankshaft #693653 is tapped at 7/16-20, has a 1/4" Keyway, is 1" in diameter and is 3-5/32" in length. Am I correct in thinking that they will interchange and the 1/64 difference in length shouldn't matter? Thanks, Mike Share this post Link to post Share on other sites
Dark 0 Posted November 6, 2007 ??you havent installed that yet?? gee 1/64th off ....I think your idler pully is probably off at least that much lol Share this post Link to post Share on other sites
firefoxz1 4 Posted November 6, 2007 These engines have different bolt patterns. Some frames have both patterns drilled in so you maybe OK there. The stack pulley should be OK. Share this post Link to post Share on other sites
Mike 0 Posted November 6, 2007 Well before I actually switch engines I am going to try and replace the blown valve seat in the 12.5 twin. Just wanted to make sure I have a backup plan. Thanks, Mike Share this post Link to post Share on other sites