FreddieFarmall 1 #1 Posted November 14, 2012 Just wondered what would be the best way to measure for a v-belt if the length is unknown? I am putting a non-stock engine on a pulling tractor. Thanks for your input! Fred P. Share this post Link to post Share on other sites
KATO 115 #2 Posted November 14, 2012 Most V-belts are measured by OD . so i would Use a piece of paper or something long and thin and wrap it around the pulleys and cut to length. then measure . Share this post Link to post Share on other sites
JackC 616 #3 Posted November 14, 2012 Put something in the pulley grooves to simulate the presence of a belt and then use the flexible tape measure that seamstresses use? Share this post Link to post Share on other sites
KATO 115 #4 Posted November 14, 2012 :text-yeahthat: Also i forgot to mention you sould add 12 inch so you can get it over the pulleys in the first place. make sure you use a premium style belt not fractional H.P. Example 4L370=12 inch wide X 37 inches od, fractional HP dont use this common hardware store belt style go to a jobber and get a good belt. Share this post Link to post Share on other sites
Tap53 57 #5 Posted November 14, 2012 Fred, easy to do if you have an Idler or some way to take up slack, if not, I can give you a formula that takes many variables into consideration,, measurements, to come to a conclusion. Such as; Vc=/[g2-2(D2-D1)2]+g Share this post Link to post Share on other sites
tarcoleo 119 #6 Posted November 15, 2012 Use a piece of rope with a general diameter same as that of the belt you want to use and run it around the sheaves involved. Cut to exact length and measure. You'll be close, and maybe add a 1/2" as suggested if you have an idler clutch allowing some adjustment. Tom in RI Share this post Link to post Share on other sites
Tap53 57 #7 Posted November 15, 2012 Better get 3 or 4 belts, find one that fits and take the others back.. Share this post Link to post Share on other sites
305 380 #8 Posted November 15, 2012 i would use an old belt of the correct width that is longer than you need. cut it and then wrap it around the pulleys. make a mark with a pen where they overlap. then measure. should get you close enuff....but get several sizes as suggested 2 Share this post Link to post Share on other sites
WheelHorse_of_course 99 #9 Posted November 18, 2012 The OD-2" will give you the ID Best bet is to measure with a tape measure then round down to the nearest inch. Buy a cheapo hardware store belt to test the fit. If that fits great, otherwise adjust up or down (liek someone said buy a couple of sizes). Ten order a real OPE belt. The cheapo belt will last until your OPE belt arrives. I have had very good luck doing it this way! Share this post Link to post Share on other sites
Trouty56 565 #10 Posted November 18, 2012 Pulley width times 3.14 divided by 2 plus other pulley width times 3.14 divided by 2 plus distance between both shaft centers times 2.....maybe..... Share this post Link to post Share on other sites
