Mower Main Pulley Bolt Removal

[crokett™]

I need to change the Main  belt on a walk behind mower.  I need to get the bolt out of the engine shaft.  A wrench just spins the engine.  I can try clamping the operator handles to lock the engine to the wheels but there is no way to put this in the equivalent of in gear but also in park like a rider.  The only other thing I can think of is a clamp on the pulley.  I have an electric impact wrench so will use that also.  Other suggestions?

[MT Woodworker]

Ok, dumb question time. Is there a flat on the shaft you can get a wrench on?
Our rider has flats on the pulley shaft, I broke a pulley drive assembly and had to replace, the shaft had a place for a wrench.
I would hesitate with a clamp on the pulley as it could deform or possibly crack...

[crokett™]

Not a dumb question. I don’t know. I’ll check more thoroughly later today

[blackhat]

First thing I would likely try is to use the belt like it was a strap wrench. Wearing a glove, put the belt around that pulley and gather it in your fist as tight as you can. Turn your wrist tighten against the pulley and apply socket to bolt.

[fredhargis]

What blackhat said, put use your impact wrench. The hammering should break it loose fairly easily.

[lift mechanic]

Very common on a spinning shaft is left hand threads. Other than that I am no help.

[jteneyck]

Hold or block the blade.  The bolt is probably threaded opposite the direction of rotation of the blade, so you would remove it by turning the wrench in the same direction the blade spins.  

John

[shifty]

If the impact wrench doesn't work, take the spark plug out and push some nylon rope in. When the piston comes up it will hit the rope and not be able to travel any further. The bolt should be standard right hand threads.

[crokett™]

Thanks for all the replies. Something was bugging me after I posted this. I looked at the parts diagram for this mower, then looked more thoroughly at the mower, and with a better light. The bracket that holds the belt on is not bolted through the main shaft bolt. It sits just forward of center on the pulley and is bolted to the mower chassis. So I did not have to remove the main shaft bolt to get that bracket off.