CRANK WOBBLE!! Updated, found problem

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Hey Jack a good balancer is good money spent you don't want this to happen again , the crank might not be as lucky next time .
 
I found a few minutes to look at it this morning and also found the problem. SEE PHOTO My only guess is that when I upped the boost the damper couldn't take the extra stress and failed. Of all the things that could have happened this is definitely not the worst. It cracked the timing cover as well, but I have a spare one of those. The crank seems to be running true so I am not to worried about it. Anybody know where I can get a decent damper quick in Canada?

Jack

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Bravo and congratulations on a cheap fix!
 
I found a few minutes to look at it this morning and also found the problem. SEE PHOTO My only guess is that when I upped the boost the damper couldn't take the extra stress and failed. Of all the things that could have happened this is definitely not the worst. It cracked the timing cover as well, but I have a spare one of those. The crank seems to be running true so I am not to worried about it. Anybody know where I can get a decent damper quick in Canada?

Jack

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That thing is a cracked up pos, how long you have that balancer for, it couldn't have been new. I've had'em last 15 years without cracks in the elastomer like that.

Btw everyone, the outer ring can come loose and wobble but the pulley is bolted to the center hub and would be as still as the crank regardless.
Glad you got it figured and that it didn't come flying through the hood on the hwy somewhere.
 
I found a few minutes to look at it this morning and also found the problem. SEE PHOTO My only guess is that when I upped the boost the damper couldn't take the extra stress and failed. Of all the things that could have happened this is definitely not the worst. It cracked the timing cover as well, but I have a spare one of those. The crank seems to be running true so I am not to worried about it. Anybody know where I can get a decent damper quick in Canada?

Jack

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That thing was JUNK when it was bolted on. Look at the elastomer. It’s had it.

That failure isn’t from a belt too tight. That thing failed. I hope it didn’t hurt other parts, like main bearings or the block.
 
BD20B5F8-831E-4D50-AF88-685D9DC04D98.jpeg


Well as being that your engine is in the car, I’d suggest drilling and “pinning” the crank and new SFI Approved balancer....... You can make a crank pinning fixture relatively easily.
 
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Well as being that your engine is in the car, I’d suggest drilling and “pinning” the crank and new SFI Approved balancer....... You can make a crank pinning fixture relatively easily.


Not sure why you’d want to pin it. The damper is press fit and if the press fit doesn’t hold it, the damper doesn’t work. The pin really won’t do anything.
 
Well GOOD! I sure am glad that's all it was and I KNOW you are, too, Jack!
 
This is kind of my own fault. When I designed and built the engine The minds that know about these things were telling me that at the usual 6 to 7 lbs of boost I was running a second key was not required as the requirement for a second key starts at around 10 to 12 lbs of boost. Me being the adventurist that I am decided to push the limits this spring and change the pulleys to give me 10 to 11 lbs of boost. It was fun while it lasted but as usual it bit me in the ***. I am just happy it wasn't worse. A new damper will be ordered today and we will try again.

Jack
 
Ati 91828e internal balance SB Mopar
I ordered mine directly from Ati as I took advantage of their custom options. I had them reduce the stock 2.25 pulley hub, to 2” as that’s the standard I.D. of a blower pulley. I also had them change the six 3/8”X16 bolt threads to 3/8”X24 as I run studs to hold the blower pulley.

918282E - Google Search
 
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About the cheapest thing to replace, good 'bad' news! Fluidamper may throw the pulley alignment off, just an FYI.
 
Damper is ordered. Went with the Mopar Performance SFI one. It was a little more expensive than the aftermarkets available but is getting here next week instead of 2 months away. Thanks to yellow rose for the offer he gave me. Appreciated.

Jack
 
So, why not run a crank hub and let the gilmer belt absorb the vibe? Hampton kits only come with hubs. Seems if it’s neutral balance, why fret? I just took my 383 crank in to be broached for a 2nd key with only a hub. Replacing the cast 400 crank with the 383 which is forged and input drilled. The Hub is like 150$. Peanuts compared to the ATI super damper, and you already have the pulley. Hampton kits, and dyers too, if I’m not mistaken, don’t utilize a damper
 
Don't happen to have one kicking around do you? They are scarce as hens teeth here and Summit says 2 months to deliver one to Canada. That is standard for all the retail sellers in the U.S. right now.

Jack

That's ridiculous. I think a lot of places are using the virus as an excuse to just do a sorry job.
 
That's ridiculous. I think a lot of places are using the virus as an excuse to just do a sorry job.
I dunno RRR, I live in Buffalo and it takes at least 30 days to get anything either way across the border and it has been that way for quite some time. Most TO or Southern Ontario cats put up a po box in Niagara Falls, NY to avoid tariffs and lengthy delays in delivery.
 
I dunno RRR, I live in Buffalo and it takes at least 30 days to get anything either way across the border and it has been that way for quite some time. Most TO or Southern Ontario cats put up a po box in Niagara Falls, NY to avoid tariffs and lengthy delays in delivery.

That's just stupid. I feel bad for our friends north of the border. We're all on the same hunk of dirt.
 
Besides agreeing with Rusty, cause well, it’s hard to disagree with rational thinking... Have you tried calling Dyers? They were more than helpful when I built my 6-71. Best prices and free advice. And they have a free online boost chart! Although my hub did come from BDS.
 
Damper is ordered. Went with the Mopar Performance SFI one. It was a little more expensive than the aftermarkets available but is getting here next week instead of 2 months away. Thanks to yellow rose for the offer he gave me. Appreciated.

Jack

I wish I saw this earlier. I was planning to put a blower on a 392 w2. I added Molnar rods and had it rebalanced, I had a second keyway added to crank and a second keyway added to 2 different balancers because I wasn’t sure about spacing or which one I was going to use. I have a Tci rattler and an Ati super damper, both double keyed.
 
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Damper is ordered. Went with the Mopar Performance SFI one. It was a little more expensive than the aftermarkets available but is getting here next week instead of 2 months away. Thanks to yellow rose for the offer he gave me. Appreciated.

Jack


Any updates??? Is it running yet??? Just curious how it’s going.
 
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