I have a 1982 Sears Gamefisher 15 hp that shears pins at the drop of a hat. I know the shear pin protects the prop and the drive shaft and all that, but it seems that they shear too easily. I buy the Frabil shear pins from my local Marine shop. I guess they are brass. Would like to use something that is a little more durable but will still break before the prop drive shaft gets jacked up. Anyone have any advice?