Clutch / Torque Converter: Ring gear wear and old wives tales

[62champ]

In a discussion not long ago, a local club member was lamenting having to replace the ring gear on a Champ pickup because of worn teeth.

I told him that I remember hearing from my Dad once that engines tend to stop in a couple of places in the entire rotation of the flywheel and that is why there tends to be more tooth wear in certain places on the ring gear. If you take the flywheel off, heat and removed the ring, flip it over and turn it a certain degrees, you can go "another round" before having to replace the whole thing.

Now mind you my German heritage family were pretty cheap (tighter than bark on a tree I have heard) so this might have just been a poor-mans way of getting thousands more miles out of a part that did not cost more than $15...

Anyone else heard/dispute this?

[PackardV8]

Yes, six-cylinder engines tend to come to rest in one of three positions 120-degrees apart. V8s tend to stop in one of four positions 90-degrees apart. So yes, the starter ring gear wear point can be moved.
No, removing and reinstalling a starter ring gear is not something even the most dedicated CASO would usually attempt.
Maybe, CASOs might want to file the idea for future reference, as good flywheels are getting more difficult to find. Finding someone who has done it a few times to show how makes the first time more of a predictable success.

jack vines

[jnormanh]

Ring gears are installed by heating to expand them so they will slip over a cold flywheel. As they cool, they shrink to a tight fit on the flywheel. You can't remove them with heat, since you'll also heat and expand the flywheel. Ring gears are removed by drilling, hacksawing or chiseling a slot so you can spread and remove them.

I suppose it *might* be possible to cold press one off without cutting, and maybe it would be okay reinstalled with heat.

[PackardV8]

You can't remove them with heat, since you'll also heat and expand the flywheel.

Guess I've just been lucky all these years. The ring gear is so much lighter than the flywheel, a steady movement of a rosebud torch around the ring gear will heat it more than the flywheel. To be sure of the heat you can pick up a 300-degree temp. stick at a welding supply shop. Lay the flywheel down so the ring can fall off the bottom. Put the heat all the way around the ring gear using a neutral flame on your torch; not carbonizing or oxidizing. Heat the ring leading the flame and keeping it directed away from the flywheel. The heated ring gear will usually drop off the flywheel, but sometimes it needs to be started off with a few taps around the perimeter with a brass drift.

Hint: before removing the ring gear, make a jig which supports the ring gear at the correct position on the flywheel. Then, when heating and reinstalling, it is a drop-on maneuver.

jack vines

[fatboylust]

Not to imply it is easy, I have on more than one occasion working with others removed a worn ring-gear and flipped/repositioned as Jack Vines suggested. What make removal possible with heat is the difference in mass between the ring-gear and the flywheel. Using a concentrated flame on the ring-gear it will expand more quickly than the flywheel allowing its removal. We waited to reinstall the gear until the flywheel had cooled completely and been chilled in a freezer before reheating the gear to drop onto the cold flywheel. The original position must be marked to insure the gear is relocated in a new orientation. All that said these repairs were performed only because replacement gears were no readily and the equipment was vital to our mission.

[52-fan]

I once bought a Lark with a V-8 that had the ring gear heated and flipped. It worked fine. The ring gear will heat and expand quicker than the heavier flywheel.
The owner had given up on finding a ring gear in a salvage yard and finally tried turning the ring gear over. Back then Standard Surplus had plenty of them, but he wouldn't listen to club members advice.

[62champ]

Just to give you an idea about how cheap of a Studebaker family I come from, a relative tells a story of back during the depression, my grandparent still used a couple of wooden wheeled wagons. He did not want to pay to have the old wheels fixed because the wooden spokes were too loose. Before they knew they would use the wagon, they would push corn husks down in around the spokes on the wheels, take the tail gate out, load it up with enough rocks, tie a rope to the tongue and then push it off into the tank (pond around here) for a given period of time. The water would expand the wood enough that when pulled out the wheels would be good and tight enough to use for a day...now that is "old school CASO".

Thanks guys

[gordr]

I have done it myself. Yes, the wear does tend to concentrate at evenly-spaced points around the perimeter, as the engine normally comes to rest between compression strokes.

So, on a manual transmission car, you can support the flywheel by the ring gear on 3 fire bricks, and heat the ring gear until the flywheel falls out of it. Then, flip the ring gear and heat it a bit more to reinstall. Best if you make marks beforehand to define your preferred "new" orientation. Done carefully, the reapir should last thousands of miles, because shifting the ring gear places the old, weakened teeth in parts of the cycle where the load on them is less than it was.

I did it on an automatic car, and had to grind off the welds, knock the gear loose, and re-weld. It worked, but was noisy. But you do what you have to do.

If you are paying shop rates, it isn't worth it, unless time is off the essence, and a new ring gear can't be sourced in time. But if you are piddling around at home, and have the engine or tranny out anyway, it might not be a bad idea to do it before a ring gear failure occurs, if you see signs of severe wear.

[Jim B PEI]

I haven't ever done it, or considered it, on a Studebaker. I did it decades ago on a Brand X when I was young and perpetually broke (as was the car) and didn't know that it 'was hard to do' LOL. Gordr always explains very nicely how you can and should do it, if you do do it. He is the original 'Studebaker Survivorman'

BTW, the CASO wagon wheel comment isn't that off the mark. I do know of owners of brass era cars that do exactly the same thing, perhaps a little more elegantly than the old days of just fording the occasional stream, but soaking to swell dry wood works for wheels, boats, and barrels. Heck, as an 8 year old at Y camp, I already knew from my dad that that is what you had to do with canoes and boats after some time out of use, say over winter, before you used them--tip them over to get them good and wet inside and out.

[Dan Timberlake]

some ring gears have the teeth beveled on one side. The bevel is supposed to face the starter gear to ease the entry of the starter gear when engaging. I'd feel a little better about flipping a gear if doing so would not present a squared tooth face to the starter gear.

[PackardV8]

Hi, Dan,

If the ring gear has a beveled and a square side, t's not necessary to flip the flywheel ring gear, just rotate it half the distance between the existing wear points.

jack vines

[kurtruk]

I presented this problem years ago to a childhood friend that grew up in his family's transmission shop and now has his own business rebuilding torque converters and doing transmission repair. My '62 Hawk had a badly worn ring gear (flight-o-matic). Kept a wrench in the car to rotate the engine to a "good" spot. Anyway, my friend says "No, you don't need a new ring gear." He grabbed a brand X gear lying around the shop. Showed me the worn teeth on one side. "The other side's good as new. We just flip 'em around. Last as long as it originally did." I believed him.

[Aussie Hawk]

When I was a mere slip of a youth, just out of my apprenticeship, I worked for a year or so in an engine rebuilding worksop, one of my jobs was to replace the ring gears on flywheels. As we sold the customers new ring gears we didn't do the flipping thing, and got them off by drilling a hole in the flat side of the gear, with the right size drill they would split and come right off. The new gears were sanded in four evenly spaced places on the side to bring the steel up silver and heated evenly on three bricks, when the steel started to get the blue tinge the gear was quickly placed on the flywheel, checked for correct location, tapped down if necessary then left to cool. I did dozens of them. Just a tip on measureing temp - Light the oxy torch on acectylene only, with plenty of soot, cover what ever you are heating with the soot. When heated to approx 300 degrees the soot will dissapear. We used to use this method to heat up warpped aluminium cylinder heads before pressing them straight, works a treat.