Hello, I have a 1997 MTD rider 600 series model # 13A5670G019. I have replaced the blades and the deck belt and reattached the deck. After reading countless posts here (Q&A's here are much better than other sites) I have decided to seek your sage advice. The blades will not disengage when the lever is pulled and set in position. I have adjusted the spring tension so that the belt slackens now when pulled but them blades keep on turning freely. How can I troubleshoot this? I just acquired the machine and don't know the maintenance history. Could this be a safety switch issue ( I noticed that a switch is depressed when the lever is pulled back to the brake position) or have I made a mess of the deck attachment? Also, the brake pads do not touch the brake disc when the brake is engaged. As you can see, I really need your help. Thank you in advance.

Hello, I have a 1997 MTD rider 600 series model # 13A5670G019. I have replaced the blades and the deck belt and reattached the deck. After reading countless posts here (Q&A's here are much better than other sites) I have decided to seek your sage advice. The blades will not disengage when the lever is pulled and set in position. I have adjusted the spring tension so that the belt slackens now when pulled but them blades keep on turning freely. How can I troubleshoot this? I just aquired the machine and don't know the maintenance history. Could this be a safety switch issue ( I noticed that a switch is depressed when the lever is pulled back to the brake position) or have I made a mess of the deck attachment? Also, the brake pads do not touch the brake disc when the brake is engaged. As you can see, I really need your help. Thank you in advance.
The brake part is easy just adjust the nut in until you can't push the mower and back it out until you can and about a quarter turn after that and they should work. For the blade stopping problem (look under the foot board and see if the blade wheel is touching the brake pad atached to the under side of the running board. It seams like the deck is not being lifted high enough to touch the brake pad for the belt wheel sometimes it is just ignored and just be careful where you put your feet

Deck engagement adjustment. Rod running from lift shaft assembly back to the rear of the deck at a downward angle, has an adjustment ferrule on one end. Controls the forward/backward movement of the deck to tighten/loosen the deck belt. If you replaced the belt, it's now going to be tighter than the old one. Shorten the rod so that when you pull the lift lever up to the blade stop position, the deck comes forward far enough to release the deck belt from the engine pulley, stopping the blades. Careful with that big spring pulling the deck back, it's a bear to remove and replace.

You also have brake pads for the bldes on the underside of the running boards. If the deck belt is loose, check the pads. They should make contact with the deck pulleys, stopping the blades. Transmission brake adjustment from JohnFitz above is accurate.

Johnfitz, loose the caps please, that is taken as shouting here. Lower case is much preferred.
Thanks,
Mowerman2468