[Deezil]

I have a little rear engine gilson rider I am having issues with. The blades dont disengage fully. It did this when I got it with the old rotted belt. It has a new factory belt now and idler pulley . The idler pulley is retracting when using the PTO lever. I tried a 1" size bigger belt but it just pops off after disengaging the manual PTO lever. The pulleys on the engine and spindle look alright save for some corrosion.

When disengaging the PTO idler retracts quite a bit and let's the belt go completely slack but there seems to be enough bite on the driven pulley to keep the deck active. I am using the correct size belt according to the manual and my local implement dealer. It's a 1/2 x 74 belt.

Could the rusty pulleys be the culprit? Wondering if it would be advisable to pull both the pulleys and wire wheel them to shine them up.

Thoughts?

 

[Tractor-Holic]

Yes,rust can "grab" the belt and make it want to keep driving the blades..
Just using the mower would eventually wear the rust off the sheaves,but if you don't want to wait you can use some emery cloth or a wire brush on them to clean them up..
They may surface rust again rapidly however..

Another thing to check is the idler pulley on many idler belt drives had a "keeper" that not only prevents the belt from coming off the pulley when you disengage the blades,the outside of the belt drags on the keeper and it acts as a brake,so it wont tend to keep driving the blades..those often have to be positioned in a particular spot before you tighten the bolt on the idler pulley ,so it only contacts the belt when the deck is disengaged..