I had a different set of problems with my 2325 MMM. First, the snap ring at the base of one of the swivel wheels (front) apparently fell off(??), so the whole thing dropped down and the washer fell off and was lost. Had to drill out a large washer to get that to fit, but daughter's R&D outfit had a snap ring... so that was a fairly easy fix.
While putting the MMM up for the winter, I discovered that on the rear wheels, the slotted spring pin that holds the wheels onto the axles (all four wheels use this method) had been ground away by rubbing on the washer(s) over the years, no doubt because of the sandy nature of the backfill put in around the house when it was built.
Half of the pin was ground away, half-way through... but the lower section was
completely gone. Turned the wheel over in my hand to get at the grease fitting... and one of the washers dropped right off! (WTH??) Then I saw the pins were worn away.
So-- if that ever happens: pins are metric, 5mm. Closest I could find locally was 3/16" (Tractor Supply), which worked, but the fit is not so tight. Have some 5mm x 40mm pins on order (Grainger).
Fist pic is front wheel, showing the pin the way it's supposed to look. Second pic is one of the rears -- note that the lower half of the pin is completely gone. Third pic is from MF parts diagram. Fourth pic is one of the 2 pins after it was removed & cleaned up.
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