I have an old murray lawnmower about 1990. We changed out the blade and now the blade constantly spins. Before I change the belt out it worked fine. It would dieengage & engage fine.
It is my 90 year old grandfathers & I cant just let it spin as it will hurt him.
What can I do to fix the blade from constantly spinning. When I cut the lawnmower off of course it does stop.

Kim Howard, June 2008

On the cutter deck there is (or should be) a mechanism that applies a brake to the belt pulleys when the blades are disengaged. This will be worn. Now you have changed the belt, there is a more positive drive - even with the blade clutch 'out'. This overcomes the drag from the blake brake and so the blade spins. Replace the blade brake pad(s), and possibly the actuating spring.

phil_saunders@bigfoot.com

Phil Saunders, June 2008