The 3-speed trans is obsolete and parts are getting expensive. Since it sat outside for two years, you really want to open up the transmission and give it a good cleaning / rebuild.
I picked up 2 3-speed mowers last year (1 $10 / 1 FREE) the 1st one's trans had water in it, but thankfully no parts were worn out ... so I was REALLY GLAD I opened it up, cleaned everything up and re-greased it !!
2nd one was dry inside but had water in it at one point as one gear was corroded and a couple of teeth were bad. The main drive shaft and 2 bushings that ride on it were bad too and these 4 parts were just under $118. It is really strange in that the bushing on the left looks ok, but the shaft is chewed up where it rides. Vs. the bushing on the right is trashed and the area on the shaft where it rides is no where near as bad as the other. The bushings are not that much $$ and if the shaft was evenly worn at both spots I would have saved $84 and done just bushings and reused the shaft. The replacement gear I got was used and was $10~15 cheaper than new. Other areas where the drive shaft can be worn out is at the the end bushings at the height adjusters.
Doug
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