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The novice guide to Bobcat belt tensioner

andyjax ยท 2015-02-24 19:42

Just went through a learn as you go process for the belt tensioner on my 773G Bobcat, so I thought I'd pass along a little newly learned knowledge for anyone out there that may need it. I changed out all the belts on my 773 and noticed that the main drive belt tensioner was not really moving the belt as I tried to tighten it as per the repair manual and the sticker on the inside of the rear door. The pointer was not budging, so I took the tensioner all the way off. It looked OK until I looked at the back side of it and saw some nice cracks in the hub assembly where the spring fits into the assembly. The hub was made of cast and therefore did not lend itself to welding, so I bought a new assembly from Bobcat. Ouch! But, if you're like me, you can't live without your baby. Anyway, put the new assembly on and still the pointer wouldn't move from the one o'clock position. After consulting a few experienced people here, I rapped on the pulley with a hammer while prying down on the tensioner bracket. Still nothing. Not going to tell you how many times I took the tensioner off and put it back on, but suffice it to say I was getting a little frustrated. As it turns out, I was using a large ( 2.5' ) construction type flat bar for leverage. I finally got big 5' pry bar out and put some pressure on the bracket, and since my only assistant as usual was the dog, I turned a 5 gallon bucket upside down and carefully placed the other end of the pry bar on it to 'hold' the pressure down on the bracket. Then I tapped sideways on the new pulley and the spring finally wound up and the pointer went to the 3 o'clock position as advertised. I slacked off to about the 2:30 position on the pointer and tightened down the bolt. Ran for 30 minutes and looked good. I'll run it for an hour or more while working it and recheck, but I think that will do it. I will also put that check of the pointer in my annual maintenance. You don't want the pointer at the extreme end of travel ( one o'clock or three o'clock ) because that is fully against the stops on the hub and that will eventually cause problems like I had. The pointer needs to be somewhere in between and under spring pressure. Hope this helps, I've taken a lot from this sight and hope this gives some back.

Replies4
  1. #1willie592015-02-24 20:06

    Good to hear you got it sorted out andyjax. Yes, it's a learning curve for all of us the first go around until you learn first hand how much prying pressure it takes to pop it from the 1:00 position. And like you I typically have to go it alone as well. I use a six foot healed pry bar myself and figure out a way to hold it in place while I tighten the bolt and hope it all don't come unglued before I get the bolt tight!

  2. #2lantraxco2015-02-24 21:24

    Willie, if you can build a suck bucket, surely you can design a patented Bobcat idler adjusting tool and make a mint!

  3. #3willie592015-02-24 21:46

    Then I wouldn't have a great story to tell when the pry bar comes loose, lands on my foot, makes me hop backwards on the other foot, and trip and fall backwards into the oil pan where I just changed the oil on the machine.

  4. #4lantraxco2015-02-24 21:53

    Well yeah, there is that.... LMAO! :notworthy