We all know that there's no workable formula for figuring out your new belt length. You've fabbed up a fancy clutch, done a pulley swap, or are scratchbuilding your new ride. You need to figure out the belt size required, and there's just no "looking it up".
You've wrapped a rope around it and measured the rope. You've tried to calculate it. You've bought and returned 10 wrong belts. You're ready to set fire to it. Don't...
I was not willing to go thru all that. I did the following, and had a direct fit, the first time, no screwing around.
You need a long belt- too long. Old is fine, you're going to kill it. Cut that belt so it's open. Now- with the clutch spring released (or off completely) run the belt through it's intended route, overlapping both ends and pulling it snug but not tight. Just enough to keep it falling off the pulleys. Now- clamp it together where it overlaps, with vise grips or similar.
Attach the tensioner spring and let the tensioner do it's job. Use this opportunity to decide whether you're happy with it, or whether it needs do be tighter or looser. Adjust vise-gripped overlap accordingly.
Now, ziptie the overlap together tightly using 3 or 4 zipties, and take the belt off.
This "dummy" belt is your exact required length. Now- I have recently acquired a belt gauge, and I expect that you don't have one. No worries- your friendly neighbourhood auto parts store does. Put the belt in the gauge, and it will tell you the size. That easy.
Look closely here- I want an "A" series belt- the gauge says "4L-640" (A62). So, I went out and bought one.
New belt, perfect fit. Only one trip to the parts store!
Subject: 
August 21st 2013, 2:09 pm
