Walker Mower Forums

[Chynoweth]

The shear pin that is located in the PTO drive unit right next to the U joint on the deck broke at about 65 hours on my new machine. I never hit anything hard at anytime with it (babying a new $12000 mower). Is this a pin that will break about every 65 hrs. with normal wear or did I maybe have a bad pin? I guess I'm wondering if I need to keep a few of these on hand?

[scsomike]

i am thinking you probably had a bad pin or something got a hold of it without you realizing it. on my old one i found a brick in some leaves (on my own property no less.. ) and it tore both of them up. but i knew it did it, hell of a noise...

[grassaholic]

You can slowly wear shear pins out by engageing the blades with the engine at too high an RPM. Walker just changed the PTO on the model MB from an electric clutch to a manual tensioner. The reason for this was the electric clutch engages too hard and caused problems with people breaking the same pin as you. If I were you, I wouldn't worry too much. The pins are cheap and easy to replace.

[mowing_freak]

I agree with grassaholic keep several pins in stock and a small punch or long nail and hammer to drive out the pins when they break. Just think of all the money you made in that 60hrs compared to the cost of pins...

[Gene_gls]

I had a problem with one of my helpers last year, engaging and disengaging the blades at a high RPM. The torque in the shaft cracks the pin, eventually it fails. I have never busted a shear pin in the drive shaft in the 10 years that I have owned it.

[audijim]

The pins P/N also states that is comes in packs of 5, so you can not buy just one.

[MOW_ED]

I have had them break at about the same interval. Maybe they used a less dense material in a batch. So far I have only replaced them about 4 times in 7 years.