Blades touching on walk behind mower

[cheramievaughn]

Hi, I ran over a rubber dog toy with my 30" Exmark walk behind mower, and now the blade tips touch each other. I have removed each blade - neither one of them are bent. I have no idea what could be wrong. This is the first cut with new blades and belt. I did notice when I removed the blades and re-installed them I couldn't orient them 90 degrees from one another. Could that mean the belt needs to be removed and re-installed with the blades 90 degrees from each other? I don't know what else could be wrong - this was my first time removing lawn mower blades. Thanks for all of your suggestions! I can post pictures if more info is needed.

 

[John Fitzgerald]

Blade orientation doesn't matter unless it's a cogged belt. If your mower has a cogged belt it may have slipped some cogs and be damaged. If not damaged, you will need to remove it and reorient the blades so they do not hit, then re install belt. The current commercial 30" Exmark does have a cogged belt. If that model, take the belt cover off, loosen the tensioner, remove and inspect the belt, orient the blades properly, reinstall belt, tension, replace everything as was.

 

[cheramievaughn]

It’s a cogged belt and I guess I messed up the timing. I removed the deck cover and the belt is fine, not popped. However the belt is really tight - is that what you mean when you say loosen the tension? I see something that looks like it may loosen it.

 

[bertsmobile1]

Not familiar with your mower but some of the timed blade mowers either sandwich the blade so it can slip or have a shear key that will break if the blades hit something .

 

[Rivets]

Put this in the wrong thread, but it still might help you out. Take off the large black cover on the front f the mower. Under it you should find the timing belt. You will see the belt tensioner also. Loosen this tensioner until the left side pulley can turn freely when you loosen the belt cogs fron the pulley. Carefully turn the left blade until it is at 90 degrees to the right pulley. Hold the pulleys in this position and retention the belt. Double check to see that the blades stay at 90 degrees.