On the small mowers that use the speed change wheel, what is the proper setup? The tire is good on this one, and it has two friction discs, one each side of steel plate. How do I set it up and what are the wear limits on the disks and pressure plate? Thanks Tom

I have worked on a lot of Snapper walk behind mowers, but I am unfamiliar with any ones that have (2) friction drive wheels.

Does this mower have a power reverse?

On most of the units I have ever worked on the driven disc is operated by a belt from the crankshaft of the engine and then the rubber friction disc is driven off of the driven disc.

Both the drive belt and the drive disc are tensioned by springs, if either one breaks or comes off then the transmission will slip.

If you can find a model number off your unit, that might help with figuring out what kind of set up you have.

Ken, picture the small tranny, which is really just a differential with a flat disc approx 7" in diameter. This is normally where you would find the pulley on the tranny input of most mowers. The rubber tire is vertically mounted on a cross shaft and can be shifted across the face of the disc top which gives speed changes as it is shifted from the center of the flat disc and to the outer edge. For reverse, the tire is shifted across center causing the differential to drive in the opposite direction.
I will get the model number and send it to you when I get to the shop Monday morning. Thanks for your reply Tom

Sounds like he's talking about a small snapper rider.

that is correct, Small Snapper rider. 12hp

Okay, I thought you were talking about a really old walk behind (small mower) as some of the very early ones did have a reverse.

I am still confused about the 2 drive discs however, this is a set up I am not familiar with.

Is this a rear engine Snapper Rider? If so then the model number should be on a triangular decal on the frame to the left side of the seat.

New information

Snapper
Extra tough
Hi-Vac
Model # 3311X6S
Serial # 73123480

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