Flywheel ring gear...

Discussion in 'U-shift em' started by FJM568, Apr 27, 2020.

  1. FJM568

    FJM568 Well-Known Member

    Anyone know a source for the flywheel ring gear? Got a couple bad teeth on mine. Flywheel is off a 67 GS400. Can't see buying new flywheel for a couple of bad teeth when ring gear isn't that hard to replace. I'm having trouble trying to find one. Got them for just about all the other brand vehicles out there, just not this one.

    May have to end up welding up the bad teeth and machining them to size.

    Thanks.
     
  2. Brad Conley

    Brad Conley Super Moderator Staff Member

    You can buy a NEW flywheel from TA Performance for like $70. Why bother looking for used?
     
  3. BuickV8Mike

    BuickV8Mike SD Buick Fan

    Welding might have un-intended consequences. It is a press fit, right?
     
  4. FJM568

    FJM568 Well-Known Member

    Manual trans flywheel, not flexplate.

    And yes, just a shrink fit, no welds.
     
  5. Brad Conley

    Brad Conley Super Moderator Staff Member

    My bad...
     
  6. FJM568

    FJM568 Well-Known Member

    No problem.
     
  7. BuickV8Mike

    BuickV8Mike SD Buick Fan

    My point is if you weld it and heat it too much it will lose its "press fit" if you will.
     
  8. FJM568

    FJM568 Well-Known Member

    Good point. I have been thinking about that since my earlier post.
     
  9. telriv

    telriv Founders Club Member

    Just heat up the ring gear with an Oxy/Cet torch & when it expands a little bit give it about a 25* turn & you will again be into good teeth.
    On a V-8 the flywheel stops at ONLY 4 spots ALWAYS. AND your just heating it enough to be able to turn it. It will NOT lose it's ability to hold while it contracts/cools.
    Done this MANY times especially on older vehicles when parts are non existent. Never had a problem.
     
    BuickV8Mike likes this.
  10. FJM568

    FJM568 Well-Known Member

    Interesting. I've heard that, probably here, you've posted that before, right? Hard to believe it only stops in 4 spots.

    The issue is, this flywheel came from a parts car. There are 2 bad sections about 3 to 4 teeth in a row that look to be rusted through or thin and missing. I think replacing the ring gear and resurfacing the flywheel to clean up some pitted areas would be good as new.

    There has to be some company that makes replacement ring gears, or at least ring gears for the BBB since someone makes the replacement flywheels that TA sells, unless they aren't exactly the same size as the stock flywheel.

    Thank you for replying. I appreciate any info you can give.
     
  11. Nailhead

    Nailhead Gold Level Contributor

    The ring gear 1241871 was used from 1964-1973 and is same whether 400 or 455. RockAuto has replacements cheap.
     
  12. agetnt9

    agetnt9 Agetnt9 (Dan)

    Did you check a flex plate to see if you can grind the welds off and fit it ? 166 tooth ,, might be da same :rolleyes:
     
    FJM568 likes this.
  13. telriv

    telriv Founders Club Member

    Have you checked the availability at Pioneer???
     
  14. FJM568

    FJM568 Well-Known Member

    Wasn't able to come up with flywheel ring gear or that part # on Rockauto.com. Could you maybe post a link to it?

    I have been thinking about that as well. So much so that I actually tried it today. I had an extra flexplate off a bad motor. I cut through the welds with a cutoff wheel on a die grinder and removed the ring gear from the flexplate. I dressed the welds and then bead blasted the I.D. of the ring gear. I then used a brass drift and removed the old rusty toothed ring gear off of the manual trans flywheel. I then set the "new" ring gear and using a brass dead blow hammer, I tapped the ring gear on the flywheel. It seemed to go on about as easily as the old one came off.

    What I think I will do next is to pin the ring gear in place by drilling and tapping set screw holes at the part line between the i.d. of ring gear and o.d. of flywheel mounting diameter. By doing that, using set screws with loctite and peened in place, it should keep the set screws from backing out and also keep the ring gear from rotating or backing off. After that is done, I'll send it out to have it resurfaced and it should be good as new.

    Here's a pic of the flywheel with the "new" ring gear installed. Still need to "pin" the gear.

    IMG_20200428_152541.jpg
     
    Darron72Skylark likes this.
  15. FJM568

    FJM568 Well-Known Member

    I'm pretty sure I pulled up their website and did a parts search for just the ring gear but found nothing for the Buick big block.

    I looked at several places with no luck.
     
  16. FJM568

    FJM568 Well-Known Member

    Just checked Pioneer's website again. Don't know how I missed it, must've done something different. Part # FRG-166W for ring gear. But the i.d. doesn't look right. I might need to measure my flywheel again, but their dimension seems way too small.

    edit...I used a 70 GS455 to look that up. Won't come up for 67 GS400. The flexplate ring gear I used is from a 76 455 motor.

    Does anyone have a GM parts book to look up the manual trans flywheel parts numbers from 67 GS400 to a 70 GS455 to see if they're the same?

    Again.. thanks for everyone's input. I will remove the ring gear tomorrow and get a measurement of the flywheel for future reference for the forum before I pin it.
     
    Last edited: Apr 28, 2020
  17. BuickV8Mike

    BuickV8Mike SD Buick Fan

    Why not a dowel pin? One position should be enough? 1/8" maybe? We did similar with aerospace parts. May also want it toward the inside from the parting-line to have more maximum diameterical support. If you understand what I'm explaining poorly. My 0.02. Mike
     
    FJM568 likes this.
  18. BuickV8Mike

    BuickV8Mike SD Buick Fan

    Honestly, I doubt you need it at all.
     
  19. Nailhead

    Nailhead Gold Level Contributor

  20. FJM568

    FJM568 Well-Known Member

    Understand what you're saying. Thought of using dowel pins, but they would still be able to "walk" out. By using set screws, the threads will prevent that and also keep the ring from possible walking. Flywheel's gonna get hot, so I didn't want to even give it a chance to move.

    Used to do this with slinger rings on pumps. Should work fine. I'd rather put them in now, than to have to pull trans and flywheel to do it later IF something did happen. Don't think it will, but it's not a big deal for me to do now.

    Appreciate the suggestion.
     

Share This Page