Edchris177
Advanced Contributor
Over the years there have been many posts where folks can’t get the lower unit off these little motors.
There are also numerous YouTube videos showing impeller replacement that completely neglects having this roll pin installed (#8) …you cannot remove the impeller cup, old impeller, or replace impeller with the pin in place.
People beat on the lower unit, eventually busting the pin,then never replace it, & don’t know why it was there in the first place. Hint: it wasn’t because the factory mistakenly ordered 10,000 roll pins, or needed to train people on how to drill small holes.
Looking at the photo, you can see the pin, at 11 & 5 O’clock positions. You can also see a slot, at 9 & 3 o’clock. When dropping the lower unit, either turn it after it comes partway down, or turn the flywheel so the two align. Lower unit will then drop. Same thing when installing, turn the driveshaft so the pin will line up with the slot before you try to push it fully up. If you don’t, the lower unit will not go all the way up.
What’s it for?
Look at the parts diagram, GEARCASE. You will see 6 parts, numbered 1-6 that form the lower crankcase seal. If you pull the powerhead, they sit in a recess at the top of the exhaust housing. They are shown in the photo, held together with a zip tie as the motor has been disassembled. NOTE: they are upside down in the photo, the shiny brass cup goes in first, it is item 6.
Notice the two little bumps? That is what the roll pin rests against, & sort of locks it to the driveshaft, so it turns with the shaft. That also pressures the spring, which pushes the carbon seal (4) & the other parts up against the crankcase.
Now you know why the pin is there, what it does…if you change an impeller on these motors, & the pin isn’t there, PUT ONE IN!
There are also numerous YouTube videos showing impeller replacement that completely neglects having this roll pin installed (#8) …you cannot remove the impeller cup, old impeller, or replace impeller with the pin in place.
People beat on the lower unit, eventually busting the pin,then never replace it, & don’t know why it was there in the first place. Hint: it wasn’t because the factory mistakenly ordered 10,000 roll pins, or needed to train people on how to drill small holes.
Looking at the photo, you can see the pin, at 11 & 5 O’clock positions. You can also see a slot, at 9 & 3 o’clock. When dropping the lower unit, either turn it after it comes partway down, or turn the flywheel so the two align. Lower unit will then drop. Same thing when installing, turn the driveshaft so the pin will line up with the slot before you try to push it fully up. If you don’t, the lower unit will not go all the way up.
What’s it for?
Look at the parts diagram, GEARCASE. You will see 6 parts, numbered 1-6 that form the lower crankcase seal. If you pull the powerhead, they sit in a recess at the top of the exhaust housing. They are shown in the photo, held together with a zip tie as the motor has been disassembled. NOTE: they are upside down in the photo, the shiny brass cup goes in first, it is item 6.
Notice the two little bumps? That is what the roll pin rests against, & sort of locks it to the driveshaft, so it turns with the shaft. That also pressures the spring, which pushes the carbon seal (4) & the other parts up against the crankcase.
Now you know why the pin is there, what it does…if you change an impeller on these motors, & the pin isn’t there, PUT ONE IN!
