Would a little heavy grease help? If only as a temporary solution? And if the ring gear is a shrink fit, it is conceivable it was put on backwards . Only way to know would be to take a look at another one. I'm in for the night, but if I remember, I'll take a look in the morning.

Many years ago, when i first started out to be a mechanic, i worked at the local Ford Dealership. One of the things i first learned was how to install the starter ring gear onto the flywheel. Of course, the learned heads there had their fun, by handing me the new ring gear and telling me to install it. They did show me how to remove the old one, by using a big chisel and hammer, and splitting it. When i tried to install the new one--well--it seemed to be too small. I took it back to the parts dept and told them it was wrong. Then a good friend showed me how to heat it until it slipped on easily! AHAH!
I'm waiting for the owner to call me. I hadn't told him about the problem, since he's been out of town.
I figure, either the factory made the mistake, or somebody local tried to fix it and goofed. (Not me!) And didn't want to buy another ring.
I'll let ya know how it turns out . RJ
ps: The teeth on the starter gear were worn off completely, and i don't want to have to buy another one, after buying the first one. No use damaging the new gear.

Well, i checked other Tecumseh flywheels, and all of them have square cut teeth on the ring gear, and the starter gear! So, now what? It is screeching again, but it sometimes will mesh and make it run.The owner came and heard it making the noise, so he left it here. Mainly because it is raining and cold. And, we didn't want to dig up my yard/loading area. All i can say is: "RATS"!
I think the Tecumseh factory was going belly-up, and the employees didn't care any more, so they messed with the machinery, and i think this one is one they did it to.
And of course, nobody is open that i can ask for advice. "RATS!"

Hi Rusty. You broke the cardinal rule and didn't post engine #s! Starter # may help too as maybe it is just plain the wrong starter. Tecumseh drive gears that have the rubber insert will squeal nicely when they get lube on them or deteriorate.

Well, today i bit the bullet, and really got into it. The problem, not the bullet.
The factory had used 2 shoulder bolts, in place of the regular ones, and slotted the loops on the starter where the bolts go thru, with the result that it didn't line up right. And, those bolts couldn't be tightened up. So, after much scrabbling around in my cool garage, and a loss of religion, i finally got it all back together. I tried it and everything works ok now. Runs and drives.
I installed different bolts to hold the starter on, and that did the trick.
One distressing thing about Tecumseh starters is the steel ring the keeps the gear and spring onto the starter shaft. WOW!! That ring is hard to get off, if you need to use it again. And, if ya ain't careful--it turns into one of those "OH,Oh, now where did it go?" experiences.
My friend at the mower shop has a neat tool that removes those rings easily. He sez they are very expensive. He also sez that Tec has changed the shaft and it now uses a bolt, in place of the J---- clip. No more crawling around on hands and knees, looking under everything for the clip that flew away! I've spent some time crawling around my shop looking for those type of clips/rings.

Good old ingenuity of Mr Rusty Jones strikes again!

Thanks, Tomplum, for the nice words.
And, after the New Year holiday, i have a nice little C-man tractor to spruce up with some paint and rubbing compound/polish, so it'll be ready for the Spring trade. 'tis a bit cool in the garage, but my Mr. Buddy heater helps some. Too cold to paint, and using the heater might produce a scary condition, like a big "BOOM!" Plus, it gives BIG fisheyes in the paint!
A local boy asked me to look at his car which he was painting--said the paint looked like liver! I guess it was too much work to remove the paint, so he junked it! Turned out--his final wash was done with gasoline! A very big no-no in the auto paint trade!
Best wishes for the new year! Our politicians will own my home, with the new reassessments! Went up greatly. Guess it was a good idea to keep our motor-home. Might have to live in it! Cheers: Rusty Jones

I hear what you say on the paint. It is such a pain to keep it all heated up to refinish in the winter. And then that sudden boom comes into play! you'll have to tie a milk cow up in the back yard and get a farm exemption on your taxes....

Yeah, ya can't use heat from the house furnace! It gets the boss lady all "het up", and makes yer life miserable for weeks, because of the stink! BT/DT once. Never again.
the idee about the cow has merit, but the Boro hot-heads would have me strung up for that trick!
And, why am i writing this late? I went to the Fire Hall, had a brewski to celebrate New Year, and ate some snacks, then went home, and checked on old Lionel train transformers, the two top handle type. $140 on Ebay. OUCH! Got one to sell, but won't get that much for it, maybe $50. G-nite!