Well this is normal.

KansasIDI

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I thought my new Napa starter’s Bendix gear had gone bad, lifetime warranty so they gave me a new one. Still spun but wouldn’t turn the engine over. Wiring all tested good. Battery voltage good. And then I found this. I have never in my life ever seen anything like this.

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Jesus Freak

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Just think, now you have an "opportunity" to do all sorts of upgrades and preventive maintenance......... cheeper then a car payment!
I wonder what would cause that? Age I guess?
I smell a ZF5 in your future!
 

KansasIDI

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I need a flywheel for a ZF5 anyway. Guess I’m gonna do that swap sooner than I thought…
Just think, now you have an "opportunity" to do all sorts of upgrades and preventive maintenance......... cheeper then a car payment!
I wonder what would cause that? Age I guess?
I smell a ZF5 in your future
 

XOLATEM

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I have nowhere near the seniority or tenure that most of you guys do and I want to aknowlege that everybody has an opinion that is valid in their world and has probably done things "their way" since Noah got his first Handy Andy Tool kit...

That being said and with my armchair expert belief (not 'knowlege') of rudimentary metallurgy and manufacturing techniques...

Flywheel ring gears for our purposes are supposed to be heat treated and have a friction fit to the flywheel unless they are welded to a flexplate. Also...they are probably 'rolled' out at the factory much like how common steel is and then bent around a mandrel and then machined to size.

When you install a ring gear to a flywheel it needs to be heated JUST ENOUGH to put in place EVENLY and not be overheated and thus lose its grip on the 'wheel and also not lose the heat treatment that was designed into it.

(here comes the rub...) I have seen otherwise pretty crackerjack mechanics heat up a flywheel with a torch and whack it in place with a steel hammer. (cringe, wince, turn away and grimace)

There is NO WAY that the 'torch' method can guarantee no loss in temper or even and 'just enough' heat all the way around the ring.

At least not by hand...that is, without a fixture that would spin the gear while heating. Any loss in temper will cause the metal to have a soft spot and stretch.

Another possibility is inferior offshore manufacturing where the machining and/or heat treating just did not cut the mustard.

What do you guys say?

I am bracing myself for the backlash....
 

Rdnck84_03

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When I do ring gears I use a cutoff wheel to cut the old one almost all the way through and break the last bit with a chisel.

For installation I put the flywheel in the freezer for a couple hours and the ring gear in the oven at 400 degrees for about 15 - 20 minutes. It just falls on, but you gotta get it lined up fast.

James
 

Nero

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The procedure I use is heat up the ring gear with oxy and a rosebud tip to about 400F, and sure as heck it dropped right on. Cooled down on its own and now it's stuck.

I guess each manufacturer has its own way to do things.
 

chillman88

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There is NO WAY that the 'torch' method can guarantee no loss in temper or even and 'just enough' heat all the way around the ring.

I don't remember the details, but I'm pretty sure there's a temperature that as long as you're under you won't remove the temper. You're not supposed to get it red hot to put it on.

That's from memory, I could be wrong. That's just my understanding.
 

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