Ugh....What did I possibly hurt???.....

Discussion in 'Street/strip 400/430/455' started by sriley531, Sep 15, 2018.

  1. sriley531

    sriley531 Excommunicado

    The curse of the green car strikes again. Did a few hard pulls with the new MT's and everything was fine. Was headed back home, cruising at 55 and heard a loud POW followed by bad vibration. Pulled into a parking lot and discovered my harmonic balancer bolt was sheared and the balancer was missing. Wlked the road (while waiting on a tow truck) and found the balancer and pulley.

    So big questions:

    Should I be worried about anyrhing internal being lunched since it ran for about 15 seconds without a balancer?

    The balancer is scraped up a bit, but no major dents/gouges. Would it be wise to reuse? (It's a romac by the way)

    If I replace it, does it need to be rebalanced? If so, would the old one be acceptable to balance to?

    Anything else I should check?

    IMG_20180915_165412580.jpg
     
  2. hugger

    hugger Well-Known Member

    It's the Nationals curse man, you are not alone, although I have never seen a what you going on there, it obviously just loosened up and walked out. I'd be tempted to look it over real good especially the hub and put it back on and see what happens
     
    Briz and pbr400 like this.
  3. TexasT

    TexasT Texas, where are you from

    So, essentially the bolt failed and the balancer came off the crank snout?

    I'd be wondering when the last time you checked that bolt? When it was installed? Not like I ever check one. Sounds like the bolt backed off and eventually the balancer beat the bolt until it failed.
    Did the bolt "bottom out" in the hole before the balancer was tight?
    Just throwing out some thoughts.
    I'd get another bolt and bolt her back on and see what happens next.
     
  4. sriley531

    sriley531 Excommunicado

    The bolt was torqued to 200 lb ft a few months ago when I installed my TA cover. That's the head scratcher, it was torqued with an iso certified calibrated torque wrench for Pete's sake. What more could've been done?!
     
  5. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    The Romac needs a longer bolt than the stock balancer. The factory bolt will only engage a few threads.

    If the crankshaft will accept the bolt still I'd throw it back together with a new balancer and forget about it. You may have issues with the key way and hub.
     
  6. Schurkey

    Schurkey Silver Level contributor

    I had a damper explode on a '66 Biscayne, 283. Main bearings spun about three months later. I never did figure out if the bearings went bad and the crank vibrated more than the damper could withstand, or if the damper exploded and wiped out the main bearings. Chicken-and-egg sort of deal.

    If your damper bolt sheared, I'd be very concerned about that short-block. As said--keyway, key, crank snout wobble, main/rod bearings, crankshaft balance...all of that and more is now suspect.
     
    Last edited: Sep 15, 2018
  7. sriley531

    sriley531 Excommunicado

    I misspoke (apologies, I'm very pissed at the moment) and it is not sheared. Just gone. I'm thinking that the detail of needing a longer bolt for the romac was overlooked. Who knows at this point as I can't remember if I bought a longer bolt or what.

    Anyway, I dont feel any major burrs or gouges on the crank, the key is still the as well.
     
  8. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    You'd remember buying it. It's a PITA to locate. I can't remember the thread size but for some reason a fine thread 7/8 is what comes to mind. Almost every hardware store doesn't go larger than 5/8 or 1/2. I bought mine at a heavy equipment repair shop.
     
  9. sriley531

    sriley531 Excommunicado

    I believe it's a 3/4-16, but I'd have to verify. (And believe me, I'll verify length this time too....)

    So what is everybody's thoughts on reusuing the balancer. It's mostly paint scrapes, but there are some noticeable dings. If I did a light polish on a late and repainted, would it be changed balance-wiee enough to cause concern?
     
  10. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    Pop it in, if it doesn't shake verify the timing hasn't changed which would indicate a slipped balancer. Otherwise you're good.
     
    GranSportSedan and sriley531 like this.
  11. Bluzilla

    Bluzilla a.k.a. "THE DOCTOR"

    Fastenal should have what you want.

    Larry
     
    Briz likes this.
  12. sriley531

    sriley531 Excommunicado

    Luckily I work for a custom industrial automation company, so sourcing hardware is rarely an issue. Sourcing Buick pulleys and balancers on the other hand.....

    If anybody has a spare March Crank Pulley laying around, I'm your huckleberry!!!
     
  13. 2001ws6

    2001ws6 last of the v8 interceptors

    Damn dude!!! Sorry your on a string of bad crap happening. :(
     
  14. Bens99gtp

    Bens99gtp Well-Known Member

    It is 3/4-16 just bought one for my romac 2.5" is too long, you need 2.25" with the factory thick washer.

    The romac should fit pretty tight to the crank. Make sure you use a proper install tool, don't hammer it on. If no tool get a longer bolt an nut and use the nut to pull it on
     
    1972 Stage 1 likes this.
  15. Dang, that had to be noisy. sorry about the run of bad luck lately.
     
  16. hugger

    hugger Well-Known Member

  17. sriley531

    sriley531 Excommunicado

    Thanks fellas. I have had a string of bad lick lately for sure (not sure it matches yours Bob, but you at least have company...)

    Ethan, I'll measure the offset on my balancer and see it the shoulder is a problem. Thanks for the link.

    Now that I've called Ed down, I'm still gonna aim to have this car at BG and run in GSR, but Im not 100% confident it'll hold up. We'll see.

    Again, if anyone has a spare aluminum pulley (or sfi balancer for that matter) available, PM me, I'm in the market!
     
  18. Bens99gtp

    Bens99gtp Well-Known Member

    My local hardware had a 2.5 for like 4 bucks that I cut down, I think at fastens it's like 10 bucks to get one
     
  19. TexasT

    TexasT Texas, where are you from

    With my budget a new bolt and making sure it fits tight on the snout and away we go.
     
  20. No Lift

    No Lift Platinum Level Contributor

    As long as the front seal surface is OK it probably is worth a try. Get the longer bolt. I think TA sells them. I always use red stud locking Loctite on that bolt and I've never had one loosen up and I'm probably not getting 200 lbs on it.

    A long time ago and before I started using the red Loctite I had a bolt come out and the damper flew off taking out the oil filter housing and I immediately shut down because the alternator light came on.
     

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