1970 Custom 10 XL eating mower deck belts

Hi Guys, just joined.....had this tractor since dad bought new in 1970, it was used until 1990 when he got sick and passed on, then I refurbished it and painted it in 1993. All has been good over the past 21 years of my usage, replaced many small parts over the years.....I know this tractor like the back of my hand but a new problem has started and I'm not sure the cause. Last year it started eating mower deck belts, so I checked the spindles (they are freewheeling and blades set at 90 degrees etc...) So I checked the idler pulley for nicks, main drive pulley etc and the cross shaft pulley. All are straight and I used a laser to align the belt to center line of pulleys. Still eating belts.... Do you think the belt tension could be the problem, it seems fine to me and I'm using the Kevlar belts now. I'm wondering if the spring that holds the engagement handle back could be weak, but it seems strong and I replaced it a few years ago. I'm thinking on increasing the spring tension....just wondering if anyone has had this problem in the past. Deck is level by the way and I cut in the medium range height, not too low......Thanks for any ideas....Rich  

I HAVE FOUND WITH AGE AND WEAR THE PULLYS STOP BEING IN A V FORM AND BEGIN TO ROUND OUT SO WHEN YOU PUT THE NEW V BELT IT DOES NOT MAKE CONTACT WITH THE PULLY SURFACE TOO WELL SO I WENT BACK TO A PLAIN OFF THE SHELF BELT THAT HAS RUBBER SHOWING IN THE CONTACT AREA ON THE SIDES OF THE BELT WHERE IT GRIPS THE PULLY. KEVLAR WRAPPED BELTS ARE SUPER FINE FOR TRANSMISSION OR DECK CLUTCH BELTS. THEIR SIDE WALL IS NOT FLEXABLE TO GRIP IN A ROUND GROOVE.
GOOD LUCK
GEORGIA SS

hi LMC , you can make a simple v-groove gauge to check the pulleys for wear, a thin, 1/16" or so, piece of hard plastic or metal shaped to the belt dimensions or you can find them online. just a thought, welcome to the site and reply with your finds or answers to the problem with your tractor. / tim

Hi guys....thanks, I will take a real close look to see if the "V"'s are actually worn at all......make up a gauge and I'll let you know.
I hope it's not the drive pulley on the engine....I tried pulling it off many many years ago with heat and it would not budge....I guess if you sat in one spot for 45 years, you wouldn't want to move either.....lol.....Thanks

Well, I checked everything and all seems to be good now after replacing the belt (still using up my Kevlar stock I already had) AND replacing the spring that keeps the tension on the belt. Believe it or not Sears STILL has them in stock.....we let you know if this holds up.....

I had the same problem. I tweaked the tensioner assembly for years. I solved the problem by simply replacing the entire tensioner assy. I now need to replace the belt every second or third year rather than two or three per mowing season.