23 mm isn't accurate enough , Norm mentioned a Tecumseh 7/8 boss would fit without the ears ,I'm sure there were images MM.
Yes I agree if I had 3 hands ,one to hold the crank from turning ,one to hold the blade plate into position and one hand to tighten the bolt then my rattle gun shouldn't be needed for routine maintenance.
I was like Norm and struggled to get the boss off without a lot of force but found a 3 leg puller even when it's not pulling perfectly straight will always remove the boss easier than 2 legs ( or 2 bolts )
I've removed at least 100 crank hubs with the 3 leg puller in the below images and lots hadn't been off in 50 years ,just using a 12 inch shifter to tighten the puller attached to the bearing plate and that doesn't pull perfectly straight because one leg pulls on the bearing remover bolt.
Haven't had a blade hub not come off , once the puller is on ,you tighten the puller bolt as much as you can with the 12 inch shifter and this alone won't budge the hub ,you need to put one side of the hub on a block of steel (train track ,I beam ,hammer head ,etc) and then use a brass drift on the hub and hit the drift with a big hammer then the hub will move and you tighten the puller again and use the hammer again until the hub just moves by tightening the puller bolt.
On old B&S motors that I was throwing out I would cut the crank shaft off with the boss and then use a press to remove the boss but I find it easier now to smash one side of the alloy off the bottom of the motor so I can get the brass drift on an angle to the boss and hit the boss off , you do get a small flat side on 3 positions on the boss by hitting it this way but no matter how rusted the boss is, it still comes off.
Disadvantages of removing the boss my way is if you hit the boss too hard some will crack on one side but this does make them much easier to remove but makes the boss useless , it's ok when it cracks if you're replacing the boss anyway.
Another disadvantage and I didn't think this was possible is I've completely stripped out the thread on my puller just using a 12 inch shifter but I expect the cheap puller is the problem as I found it thrown out at a scrap metal yard even though it looked brand new when I found it .If you spend more and buy something well made it usually lasts a lifetime .
