I started a thread a while back about too-frequent belt replacement on my lightly used 7 year old Pony mower.
The first set of belts lasted 3 years, and each successive set has lasted less and less, until the last started slipping after only TWO mowings.
It was suggested that the Variator Pulley was likely hanging up, and sticking, not allowing the center sheave to move freely and apply pressure to the belts.
I ordered an new Variator (about $50) and just installed it, and had questions.
First, the old one upon removal appeared PERFECT. The center sheave slides freely on the center shaft (barely tilting the shaft from horizontal allows the sheave to slide from one end to the other and back). The bushing is not worn, and so there is no wobble to the center sheave (0.008" on a dial indicator) vs. 0.010" on the new one, in fact. Both allow the sheave to slide exactly the same when tilted, or moved with a finger.
There is an adjustment shown by the Red Arrow #1 that is ALL the way out right now, and I am wondering if that is correct.
When the clutch pedal is completely released, there is a "free throw" of only about 1/8" before the pedal starts moving against the spring, eventually opening slack in the main belt (deck belt?), but moving the adjustment would not seem to change that. With the clutch released, there's what appears to be plenty of tension on both belts to me.
Obviously if the belt were kept from being under proper tension, it would slip, but when operating the mower, the clutch "catches" quite a while before it is fully released, so I don't think that's the problem.
Before I replaced the deck, I wanted to ask for opinions.
I did NOT change the belts this time since the new ones have only about 3 hours use, and "look" just fine. They are NOT MTD belts, however, and some have said that ONLY MTD belts can be used with the variator drive system.
If it still slips, I guess I will go pay $65 for a set of MTD belts, but having just spent a LOT on belts and pulleys, I am reluctant to throw more at the mower "this week" at least.
I frankly cannot see WHY it's slipping. It usually is MUCH better when cold, and after 10 minutes, the slipping starts, and by the time I finish my sloped lawn, I almost have to get-out-and-push to get it back to the barn.
Pushing the clutch in and releasing it will sometimes help a tad for a few seconds before the almost total slipping recurs. If on perfectly level ground, the tractor WILL always move OK. It takes at least a slight slope (or the steering wheel turned on level ground) to feel the slippage.
I posted a couple of photos below to show the old vs. new, and the new pulley installed. I have one photo before removal of the old pulley, but it's absolutely identical, so didn't bother posting it here.
The ONE "good thing" (I guess) is that I now have enough practice so I can remove the deck in mere minutes. The first time I did it, it took me a while to find all of the fasteners under the decals to get it off.
BTW, when replacing belts, if they both look and feel good
(not hard glazed), is one of them usually the first to "need" replacement. In other words, does one of the belts tend to "last" longer than the other, so replacing one belt will restore performance? It would be a way to save $30 if one typically lasted twice as long as the other. Only ONCE did I actually see or felt any visual damage (the edge of the shorter drive belt was torn up a bit on one edge) of any belt I removed. I assumed they were slipping because the edges of the "V" portion had lost their "grippiness", but it's gotten ridiculous with belts slipping badly in days or weeks after replacement. SOMETHING has to be going on here!
The mower guy at Lowes (where I bought it) said the Pony is a "trow-away" after 5 years, and that they just wear out so completely that they cannot be fixed, but dog-gone it, I see NOTHING in my unit that indicates any wear, sloppiness, or other flaw in the drive system (unless I don't know where to look, which is why I am asking here
I've owned several automotive shops over the years, and have been a licensed aircraft mechanic for almost 40 years-I ought to be able to keep a darned mower going! This is FRUSTRATING!!