A tale of 4 belts (auger belts), a 1/2" MATTERS!
I recently worked on a 5 year old Lowe's MTD Troy Built Chinese engine 24" snowblower.
I was called because it wouldn't start, old gas, very old gas, drained it, put new gas in it, started on 1st pull, even ran pretty good, no hunting, surging. I filled it with my gas that has Stabil and Lucas in it, gave them a medicine bottle with Stabil and Lucas for 1 gallon of gas.
While inspecting the machine for other issues, the auger belt was too loose. Even after adjusting the idler pulley it was flapping around really a lot when idling, hitting the metal sides; and then too much when engaged almost hitting the sides. I took the belt off, measured it as 37", the specs call for 35". Whoa, 2" difference? No wonder it was flapping so much. So I ordered the 35" belt it called for, I could barely get it on, it was so tight, even worse removing it with the idler pulley removed, it would have ruined any bearings. Why was it so tight? I told the homeowner that MTD owns a number of different brands and makes a lot of machines on their assembly line and they probably ran out of the correct size pulley and put on another and then a suitable length belt to make it work. That's why the discrepancy between the specs and the belt length needed. I also gave a push to buying locally instead of from a Big Box store as they will have assembled some of the machine and hopefully given it a good check and adjustments and have caught this issue.
I then ordered a 36" belt, installed it, it engaged fine but when not engaged it wasn't slipping enough, slipping just a little, and then the belt started smoking because of the lack of complete slippage. Whoa, turned that machine off real fast, seemed like it wasn't fast enough! I pulled the key on it. First thing I could think of and grab a hold of. I didn't want to wait for it to idle down or not shut off with the idle lever.
Again, ordered a 36 1/2" belt, all the while checking my inventory of belts hoping to have one in stock of the correct size of course, but No. When I put this belt on, of course it slipped on much easier than the others and seemed like this was going to work but I had no other options! I knew it was going to be the right size. I started the machine, the belt did not smoke, engaged and disengaged the auger several times, no slapping, no smoking, slipping the right amount. Success, now I could leave.
The downside to this? I had to loose the bottom bolts and remove the top bolts to tilt the machine to push and pull and squeeze the belt in EACH TIME. Also I did not have the machine home with me, I had to go there as I don't have a pickup truck or trailer. The positive side, it was in my neighborhood, about 1/2 mile away.
I explained to the homeowner I called 3 mower stores and none of then had any of the belts in stock and they would order them. And this time of year, they needed a $100-$150 order and could easily wait 2-3 weeks for them to get the belt in, I waited 2 1/2 weeks for a spring that I was told be here in 4 days! Besides they charge you an arm and a leg for a service call, charge you for in shop. And not sure if they would have given up and put the original belt back on again and tell you it was fixed.
The summary - a 1/2" matters, measure your belts, don't trust the specs, don't trust the belt manufacturers for an accurate size, use your intuition and experience.
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