Why does my snapper riding 42 inch cut mower blades do not engage

SOURCE: craftsman 42" riding lawn mower blade free spinning but wont cut

It sounds to me that you need a new mower deck drive belt, or your blades need sharpening. If the blade edges are rounded, they won't cut butter... Also, when mower is off, check mower deck drive pulleys to make sure you don't have any that are locked up or are dragging. You can check this by pulling the belt away from pulley and spinning the pulley by hand. MOWER MUST BE OFF before attempting any of these checks. You would be surprised how many people would try this with the mower running.
Hope this helps

SOURCE: Craftsman 18.5 briggs/str 42''won't cut

It sounds to me like a very loose belt or very worn out belt and also an adjustment problem.

SOURCE: Craftsman 42" mower deck won't disengage

Try pulling on the cable coming down to deck. This cable might be your problem. Also check that the spring on the end of this cable is present and functional.

SOURCE: Craftsman 18.5 riding mower when I engage the

craftsman decks have a positive stop adjustment for the decks. A spring atached to the blade ingadgement arm pulls the tension pully into position if the cable is rusted inside the sleeve it wont put enough pull on the ingadgment pully and thus the blades dont spin full force the belts on the mowers have no adjustments only the pully . second thing is you may want to drop the deck and clean around that pully by scraping any rust off the surface under the pullys slide good luck

SOURCE: I have a 15.5 HP Sears Craftsman 42

I'm betting that you need a new safety kill switch - probably the one underneath the seat (the spring-loaded plunger switch that won't let you use the machine without your *** in the seat). Could also be the one behind the "dash" that is associated with the blade engagement mechanism.

I know that the under-seat-switch cannot be bypassed or it will disable the machine in the exact way that you described. Why do I say this? Because I just tried to bypass my own "***-in-the-seat-safety-switch" on my very own 15.5 HP, 42" Sears tractor, and it responded by punishing me - the absense of the switch caused the motor to cut out when I tried to put the machine in gear AND/OR engage the blade. It seems to have some measured capacitance - the absense of same seeming to interrupt the ignition timing enough to shut the motor down when you attempt to get anywhere past neutral or engage the blade. These "safety" switches may be needed by a very few who prefer to be drunk while they mow lawns on steep slopes that their tractor mowers were not designed for, but I find these items to be troublesome and enfuriating. My trees shed a lot of sticks in high winds, and I can't stand shutting the machine down and restarting it EVERY SINGLE TIME I have to dismount to clear sticks or other obstructions out of my mowing path. This is an obnoxious, "nanny-design" feature that desparately needs to be discontinued. It also makes both jump-starting the tractor and electrical troubleshooting much more difficult than they should be. The tractor should let you dismount without shutting down, as long as you have disengaged the blade and shifted into neutral. It should also let you jump start with jumper cables - impossible to do with your rear end in the seat. By the way, call Manufacturer's Supply, Inc. at 1-800-826-8563. They may have a replacement - their item number 31-9664 might do it, but talk to them first. I'm calling them tomorrow. Good luck.

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