Can't get blade belt tight 2006 toro lx420

[Teeton]

Well I got a 2006 toro lx 420 18 hp kohler with about a 42 inch deck. A friend gave it to me.. I got it runner.. Great!! But,, the blade belt will not tighten up. The pulley that tightens the belt goes all the way back and it has another pulley on a spring and that's working as it should. Nothing is bent, pulleys are not wore ( changed them) belt was changed and matched old one. What can I be missing. It looks like if I get a belt that's 2,3 or even 4 inches shorter and that would work..

 

[bertsmobile1]

Some questions
1) was the mower actually running when you got it ?
2) what was the size of the belt, should be an A 109 & 3/8
3) are you sure the belt is on the pulleys as they tend to fall off the spindle pulleys when being threaded.

 

[Rivets]

The deck belt on that unit makes some very weird turns and I suspect you don’t have it routed properly. Go to Toro.com with your model number (under the seat) and in the parts area you will find a routing diagram.

 

[Teeton]

Thanks guys,, I did have the belt on right.. Didn't fall off and I even checked the lent of the belt, 109 x 1/2.. Now I got a 108 belt put it on and it works great.. Ran it 3 hours today with the smaller belt.. Thanks again Ed

 

[bertsmobile1]

Have a close look at the pulleys after a few mows and see where the new polished areas are.
Chances are they are deeper into the V of the pulley.
Fitting a shorter belt is some thing I do on occasions to stretch the life of a set of pulleys a bit longer or to compensate for flogged out mounting holes allowing the deck to sit closer to the engine pulley than when new.
I do try to get the customers to replace the worn parts where the are available as a shorter belt is only a temporary work around.

 

[Teeton]

Have a close look at the pulleys after a few mows and see where the new polished areas are.
Chances are they are deeper into the V of the pulley.
Fitting a shorter belt is some thing I do on occasions to stretch the life of a set of pulleys a bit longer or to compensate for flogged out mounting holes allowing the deck to sit closer to the engine pulley than when new.
I do try to get the customers to replace the worn parts where the are available as a shorter belt is only a temporary work around.

Hi,, I have not been on here since I got it working. Funny thing is nothing looks bent or wore. The holes where you mount the deck look good, pretty much round not slotted like wore. With the old belt the tightening pulley would go all the way back and push on the inside of the belt that that came from the outside blade spindles. Since I put the 108 belt on the tightening pulley stops about 2 inches from that inside of the above mentioned belt and all is working fine.. Right from when I put the 108 belt on and many cutting. Thanks again,, Ed