Small Engines (Lawn Mowers, etc.): lawnmower will not stop going, variable speed pulley, sheave

Question
I have a mtd (husky 18.5, 46 inch cut riding mower)(model   
13AS608H131) and the mower will go in reverse and forward but will not stop.  I have replaced the front drive belt with a 90.5 inch belt which is what it calls for and the rear drive belt is 754-0468.  I can take off the rear drive belt and the front drive belt will stop like it is supposed to.  I can give it gas and it does fine with rear belt off, but when I put the rear drive belt back on the wheels will still run and it will not stop.  I hope you can help because I have done a lot of work on this mower for me to hit a tree to stop.  The brakes does not seem to stop it either but when you release the gas pedal it should stop.  CAN YOU HELP?

Answer
Hello Patrick:

Is the Center Sheave on the Variable Speed Pulley Moving Free from One Side of the Pulley to the Other? If No, then Remove the Belts and Clean and Lightly Lubricate the Center Sheave so it Moves Freely from Side to Side. Have the Brake Pads been Adjusted? You can View a Breakdown/IPL of this Mower at this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select the Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM and Enter the Model Numbers. Then Double Click on the Model in the Results Area. Now you can Select the Section of the Mower you Wish to View. Select the Differential File. Breakdown # 19 is the Brake Assembly. Tighten the Center Nut Until Snug. Now Reverse the Nut 1/4 Turn. Make Minor Adjustments from here. Either Tighten or Loosen the Brake Assembly as Required for Proper Operation. Both the Brakes and the Variable Speed Pulley will Cause the Problem you Described. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John