edwroy 138 #1 Posted September 23, 2011 I have a 1991 520 H repowered with a honda 24 hp. Have mowed with it for four years. Now I broke 3 belts in 3 weeks. Using a oem toro belts. Anyone have any ideas? Everything seems in line, bearings tight, etc. Appreciate your thoughts. Share this post Link to post Share on other sites
zieg72 209 #2 Posted September 23, 2011 2 questions? Does it have the the spring loaded 60" mule drive? Do you have it on the inside PTO pulley? Share this post Link to post Share on other sites
JackC 616 #3 Posted September 23, 2011 Seems strange to go 4 years with no problems and then break 3 belts in 3 weeks. Possibilities are incorrect belt routing, incorrect belt tension, a pully is worn, something is out of line, or Toro is now sourcing their belts from Hong Kong to save a few bucks in this lousy economy. If the belt routing is correct and the pulleys are not worn and nothing is out of line, maybe try a Gates equivalent? Also, if the belt tension is too loose the belt could slip and possibly fail due to overheating from excess friction. Toro is not Wheel Horse so the quality of the belt could be suspect. Share this post Link to post Share on other sites
JackC 616 #4 Posted September 23, 2011 Also be sure the pulleys are clean and not glazed over from a prior belt failure. Share this post Link to post Share on other sites
Herbl 10 #5 Posted September 23, 2011 Are you putting the PTO belt on the bottom of the mower decks drive pulleys, unlike the other WH decks the PTO belt goes on the bottom pulley on a 60 "....just asking... Share this post Link to post Share on other sites
kpinnc 10,956 #6 Posted September 23, 2011 Just an idea here: Remove the deck belt (the one that stays on when the deck is removed from the tractor) and make sure the spindles spin freely one at a time by hand. I've broken belts when a spindle bearing seized up before, and I greased them regularly. 24HP is plenty strong enough to turn a sticky spindle shaft, but all of the stress will be on the belts. Couple that with the length and number of turns the PTO belt makes, and it's gonna be the weaker of the two. Good luck! Share this post Link to post Share on other sites
edwroy 138 #7 Posted September 24, 2011 Thanks for the suggestions. I removed the front belt guard and mowed for two hours. No problems. The guard appears to be the issue. New one $ 75.00. thanks again Share this post Link to post Share on other sites
Don1977 604 #8 Posted September 25, 2011 I don't know anything about the one you have. One the smaller decks the Mule drive belt guard has a rod that fits into a slot on the mule drive. Mine broke off and was letting the guard rub the belt. I welded in a new rod to fix mine. I know they added a lot of extra guards to the later ones. Share this post Link to post Share on other sites
