OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Four Stroke Lawn Mower Frames Morrison 3 in 1

Hi all
I have a morrison 3 in 1 mower and im preparing it for sale ie: new diaphrame (althought it doesnt really need it, it may help to improve the sale price and for $10 its easy), and a new blade.
The "ninja" style blade on this site is the one i assume this mower uses https://www.outdoorking-forum.com.au/index.p...;cPath=1_17_392_393&products_id=1618
But i really do fail to see how it would connect onto the moter.
The motor is a 3.5hp briggs made in 1985 with the vertical pull starter. The "original" boss is pretty much just a sleeve with no other holes taped into it and it would only be about 15mm bigger in diameter than the crank.
The centre hole of the blade is said to be 16mm well the thread in the crank would be no bigger than 12mm.
Does this blade use a special Boss which i dont have. I do have another boss and i could use a cutting disc instead but it might not mulch as well.
thanks.

Hi Jeffro,

You will need either of these two blade bosses depending on the crankshaft diameter.

7/8" Shaft or 25mm Shaft