country Posted October 26, 2004 Posted October 26, 2004 Part way through mowing my yard Sunday, the mower deck belt that drives the spindles began slapping excessively, beating against the deck, etc. I stopped and began to check all of the pulleys and spindles, to find that the tensioner pulley bearing was shot and the tensioner pulley could wobble all over. I replaced the tensioner pulley yesterday, assuming I had fixed the problem. The pulley had to be replaced anyway. I finished mowing yesterday, but it still had excessive belt slap. All the pulleys and spindles are now in good condition. I have a couple of ideas. One is since the belt is old, maybe it has stretched and weakened enough to allow the slapping. Two is maybe the old original tensioner spring finally weakened enough to allow the slapping. Three, I have both problems. Has anyone else experienced this? What was the fix? Thanks in advance for your help.
johnmonkey Posted October 26, 2004 Posted October 26, 2004 Is the belt underneath the belt guide? (the little angle bracket by the idler pulley)JH
Dutch Posted October 26, 2004 Posted October 26, 2004 1) Make sure the belt is the correct one. 2) Make sure the belt is routed properly. 3) Make sure the arm that the idler pulley is attached to pivots freely (a rusted or binding pivot is a very common problem). The pivot may have a bushing between the idler arm and the pivot stud or bolt. Take it off and completely apart to lube. 4) Make sure the idler arm spring is in the corrrect deck hole (slot) and that it is pulling in the correct direction. [img]http://www.simpletractors.com/operation/42_mower/belt_align_small.jpg[/img]
PhanDad Posted October 26, 2004 Posted October 26, 2004 Dutch said it all! Nothing more for me to add except if you're running without the deck covers, maybe the belt channel on the rear of the covers fixes your problem.
Dutch Posted October 26, 2004 Posted October 26, 2004 It just occurred to me that maybe Country is talking about the belt from the PTO. ?
country Posted October 26, 2004 Author Posted October 26, 2004 I am talking about the spindle belt on the deck per Dutch's diagram. The longest straight length of belt between the outer spindles has always flexed some, noticable by the slight rub marks left on the deck. But it was never this bad, never audible until the tensioner pulley went south. The deck covers have never been on the deck. The only thing that has changed is the tensioner pulley. The belt is still the same, the spring still the same. I did diassemble and clean and relube the tensioner bracket pivot, per Dutch #3. The belt is routed correctly, and I never removed the spring from the deck, only from the tensioner bracket. This is why it stumped me. I was able to finish mowing my yard, but I don't expect the old belt to last much longer slapping as bad as it is know. It's the end of the season, but maybe I'll start with new belts and see what happens. Thanks all.
Dutch Posted October 26, 2004 Posted October 26, 2004 How did you "diassemble and clean and relube the tensioner bracket pivot" without removing the tensioner spring? If the tensioner spring is hooked correctly, that would be impossible. I'll bet your tensioner arm does not have full travel, is binding, or the tensioner spring is not installed correctly. Any of those things would cause the belt to be loose. Better check it again.
Chris727 Posted October 26, 2004 Posted October 26, 2004 I've been told that belts don't stretch, its usually some adjustment or spring problem. I have an old sears suburban with excessive deck belt play and I believe my problem is the spring is bad.
Bunky Posted October 27, 2004 Posted October 27, 2004 Well I have seen where a belt has stretched I bought a Mf Gear drive once they said it was working fine all summer, then when they got it out in the spring it would slip well the belt had stretched over the winter and the pulleys had to be readjusted... But I would have to say check the tensioner ...
MikeES Posted October 27, 2004 Posted October 27, 2004 My bet is the belt is bad. You may have lost some of your belt when the idler went (not as deep or narrower), and now the cross sectional dimensions of the belt are not absolutely equal all the way around the belt. This causes the belt to speed up and slow down as it wraps around the drive pulley (esentially changing the effective diameter of the drive pulley). I installed a brand new drive belt on my HB212, when running the idler pulley was jumping up and down. I changed and put on a different belt and the idler pulley hardly moved. Looking very carefully I noticed that the depth of the 'V' was a little shallower for about 8" of the belt.
country Posted October 28, 2004 Author Posted October 28, 2004 Dutch, for clarification, I did remove the spring, from the tensioner bracket. I removed the pivot bolt for the bracket, which also serves as the lift point for the deck. I then removed the tensioner bracket from the spring, so I did not have to remove the spring from the deck. There is only one hole for the spring on the tensioner bracket. That's why I say the spring is in the exact location as prior to disassembly. I didn't even notice there are additional holes in the deck for relocation/chaning tension of the spring. Had I removed the spring from the deck, that could very well have been the issue. I'll have to inpsect the belt better and double check it's condition. Chances are it has some worn areas. I didn't check when I put it back together, thinking the only problem I had was the tensioner pulley. I'll also double check the tensioner arm and make sure it has full travel. Thanks again all.
Dutch Posted October 28, 2004 Posted October 28, 2004 Don't forget to double check the bushing inside the pivot arm. If that bushing doesn't move freely, the arm will bind when the pivot/lift bolt is tightened. That bushing usually rusts up and it appears to be part of the pivot arm. It is a separate piece.
country Posted October 30, 2004 Author Posted October 30, 2004 I found something, but not sure if it's causing the problem. There is excessive wear between the tensioner arm and the bushing it pivots on. I can move the arm vertically around 1/8" - 3/16". It's become pretty sloppy. I checked the belt, and visually it appears to be fine. The tensioner arm also moves very freely. I'll work on a new bushing and see if that helps first.
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