Michael Graham wrote:
>>I know this has been discussed over the years having searched through the
>>archives. But here is my question: The ring gear on the TR6 definitely
>>looks backwards to me, and several people in the archive stated that they
>>had "reversed" it and reinstalled it with the bevel toward the starter. I
>>am getting my flywheel resurfaced and am inclined to reverse the ring gear
>>at the same time to have a "clean surface" next to the starter. Has anyone
>>on the list done this reversal and what have been the long-term effects?
>>Any good reasons for not doing it? Any starter engagement problems?
>>As usual, thanks very much for any assistance.
>I realize that there's been some controversy on this topic, and I
>can't explain how some people apparently have had success with
>putting the ring gear on with the bevel AWAY from the starter. That
>boggles my mind.
>The DPO of my car didn't have the brains God gave an artichoke.
>When he replaced the clutch, one of the many things he screwed up
>beyond belief was this: He made the keen observation that one side
>of the ring gear was beveled. In fact, he mistook this bevel as a
>sign of WEAR. So, he removed the ring gear and flipped it around so
>that the starter would have 'fresh' teeth to bite on. He TOLD us
>this... this isn't just what my dad and I surmised at the time.
>(this was in 1986) And in fact, he had been going through starters
>left and right... so much so that the day we took it home there
>actually was NO STARTER on the car. We had to push-start it. The
>starters that he had taken OFF of the car had damaged bendix drives
>and the DPO couldn't figure out why. Obviously, the starter was
>having great difficulty slipping into mesh with the ring gear, even
>to the extent that it was damaging the bendix drive. It wasn't long
>after bringing the car home that dad and I had to tear into the
>clutch. (it barely worked at all) and in the course of that
>endeavor, we removed the ring gear and had it re-installed
>bevel-side TOWARD the starter. In 1988 & '89, when I rebuilt my
>engine, I had NEW ring gear put on, just as a matter of course, and
>when I picked it up at the machine shop I immediately noticed that
>they had installed it bevel-side AWAY from the starter. I demanded
>that they reverse it and when my engine and newly rebuilt gearbox
>went back in, it had a brand-new ring gear with the bevel facing the
>starter. Since I've owned the car (and that's 14 years) I've
>replaced the starter exactly ONCE. And that was simply due to
>normal wear and tear... nothing unusual in the least about that
>The other thing I'd like to point out is that if you give the matter
>some serious thought, there cannot possibly be ANY reason, on a TR6,
>to put the ring gear on backwards. On a GT-6, however, the starter
>engages from the REAR so in THAT case it IS logical. But I ask you
>this: The engineers at the factory spent a certain amount of effort
>to design a bevel into that ring gear and the machinists who
>manufactured the ring gears put effort into MACHINING the bevel into
>the ring gear. On a TR6, what would be the purpose of installing
>the gear backwards? Whatever purpose that bevel is supposed to
>serve cannot POSSIBLY be served with the bevel on the back side
>where it doesn't interact with any other parts. In other words, if
>it was SUPPOSED to be installed facing AWAY from the starter, then
>the factory engineers would have been wise to omit the bevel
>altogether... wouldn't you think? Why would it be necessary at all?
>Conversely, there obviously IS a benefit and purpose to installing
>it toward the starter. It makes it much easier for the bendix gear
>to engage the ring gear. The same thing is done to the dog teeth in
>your gearbox... the dog teeth have to fit into the synchro hub
>splines in order for the gear to be engaged. And each and every one
>of those dog teeth has a bevel and those bevels face the synchro
>hub, not away from it!! This makes it much easier for the synchro
>hub to "find" the dog teeth and leaves virtually NO surface area
>with which to clash... the bevels on the teeth guide the hub into
>mesh with the teeth when you engage a gear, after the synchros have
>equalized the speeds of the hub and gear. It's the same principle.
>If someone else has some logical explanation as to what purpose the
>bevel serves when faced away from the starter, please step forward
>and make yourselves heard. I'd love to hear it.
>Perhaps the angle of the bevel creates a particular air current
>within the bellhousing while the engine is running that is useful in
>Best of luck!!