I have a Lazer Z that has about 30 hrs on it. Sometimes when going up a hill or taking off suddenly the belts squeel. It seems as though the idler arm or whatever you call it is not moving as freely as it should. I greesed the fitting and this helped for a while and then it started again. You could push on the belt and it would not snap back very fast and the tension was not as tight as I thought it should be. I believe the spring is strong enough but the idler arm or whatever the correct term for it is is not moving freely enough to allow tension to be correct. Finally I loosened the bolt slightly that holds the idler arm on and this solved the problem. Now the belts stays tight and the idler has freedom of movement. The people at exmark say that this bolt should be tight but if I tighten it then the idler arm just doesn't move freely. I am speeking of the belt behind the seat that goes to the pumps. I know its under warranty but I would like your thoughts as to what I should expect from Exmark on this. Should they replace the idler arm and or spring.. Maybe greese isn't getting into the bearing or bushing the way it should. Any input would be welcome. I'm not much of a mechanic.