Rust patching
 

I have a couple small holes in the mower deck of my 100 and a couple in the plate that covers the transmission where the dash bolts on what's the best way to fix them and also can the cover be replaced or is it welded to the frame? Also 3rd and Rev keep kicking out what would cause this?

Weld up the deck! And tighten the tension nut on your throttle lever

The nut on the throttle lever? He Said the trans is popping out of gear not the engine speed sliding down. I'm thinking worn or bent shift fork in transmission?

Oh.. I saw REV.. Missed 3rd somehow. Thought he meant REV as in RPM

If you have rust through on a deck or any metal,determine where the metal is good/full thickness.
Then cut a patch that size, and lay it on the deck and scribe the outline carefully on the deck.
Cut out the rusty part with a cutoff wheel in a die grinder, and weld in the new metal, and finish by grinding the weld flat.
nothing special, just normal rust repair procedure.
A quick and non craftsmanship repair, would be just scab a patch over the rusty area like a band aid or duck tape, not very pretty but functional to keep debris from escaping.

I prefer the cotton candy approach for "non craftsmanship" method :biggrin2: