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Discussion Starter · #1 ·
So along with the crack in the subframe I recently posted, here is another issue.
Have a vibration. Happens at about 2100 rpms in all gear, more noticed in 2nd 3rd.
Yesterday, after trying to figure this out, I realized it happens when parked, so I guess this norrows it down. I have the Classic Chevy frt/rear nounts.
Nothing looks loose, and motor mounts seem tight. I recently re-installed my 700r4 after it was rebuilt w/new t/convvertor also. I took the three bolts out and rotated the t/conv 1/3 turn and re bolted. Still there. Flexplate looks good and appears to have no cracks. On removal of trans, I did unbolt t/conv firts so trans pulled away from engine cleanly without hanging on it.

Can I unbolt the t/conv and start engine w/trans bolted up to see if it stops? There is about 1/8inch of play there that the conv could go back into trans. Just not sure if it will move around or break something?

Any thoughts here would be helpful. Vibration was not there before re-install of trans, and trans rebuilt by very good trans shop. Thanks as always,Phil.
 

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Yep, remove torque convertor bolts from flexplate and push the convertor back. I did this once but I had to hold the convetor in place by hand. I was trying to find a knock. If you do this, watch out for the flexplate cause it will remove skin rapidly! :sign0020:
 

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check the convertor to see if any weights falling off during install. i had a vibration once and found a convertor to be bad:anim_25:
 

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Yep, remove torque convertor bolts from flexplate and push the convertor back. I did this once but I had to hold the convetor in place by hand. I was trying to find a knock. If you do this, watch out for the flexplate cause it will remove skin rapidly! :sign0020:
Sounds scary Hafrod :eek: Be careful with that...Phil!
 

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First I think I'd put a piece of string or rope between the torque converter and flexplate and my hands. That will allow you to do other needed things while this test occurs.

Second, unless the flexplate was replaced too, the torque converter is the most likely suspect. It's not unusal to see a balance weight on one from the factory. And a rebuilt or modified converter may or may not have been reassembled with the same indexing, or being re-balanced.
 

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sounds like your trans guy got a convertor that was poorly balanced . i would suggerst taking it back to him and have him get it reballanced . JMO:happy0030:
 

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I agree with the torque converter - and yes you can slide it back and run without it connected - have done this many times. Use WIRE though - not a rope - to hold it back. Run it through one of the stanoffs and then to one of the inspection cover bolt holes - twist tight enough to hold it back - but not so tight as to pull it down (if you pull it downward the center hub may hit the crank and then it won't index right afterward).
 

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Sure sounds like a poorly balanced rebuilt converter to me. If the vibration is gone when you run it with the bolts out you will know for sure. :anim_25:

-Bruce
 

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Discussion Starter · #9 ·
well, here is a long overdue update.
First, happy new year.
Anyway, gas tank was leaking for months. Daughter started college and the tank had to wait. Finally, got new tank in Friday night and installed. Went very well. Filled her up and took a maiden run Sat am. It felt great to be on the road again, untill I was reminded of that terrible vibration.
So, here's where we left off. I removed the three t/conv bolt and bungied it back toward trans as not to rub or hit flexplate. Lo and behold, absolutly NO vibration whatsoever! Now, I am so pleased, yet dissapointed that I now have to remove trans again, on my back.
I am assuming this is a convertor issue, No? Yes? Could it be the trans?

Now here is further part of story...I never really talked about this. I got my trans from Phoenix transmissions. When first installed, it was wonderful and I coulnt rave enough. Then I had a problem at about the second season end w/new trans and car wouldnt go. Took trans pan down to find shavings. Long, very long story short, these guys took trans back almost ayear past warranty end, and sent it back, fixed w/new convertor. Other one was destroyed inside. Didnt charge me a dime, and I was thrilled. Not even for shipping! These guys are the best! Now, sicne install in 7-8/2010 and very few miles, its been vibrating ever since. I hate to call back again cause service was so great. But, somethings wrong. I feel like maybe something wasnt fixed, how would I even know? This trans was originally alot of cash and I really dont drive my car that hard.

If I thought it was the convertor, I would just call Summit and order a B&m or something. Your thoughts??? Phil
 

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IF the bellhousing to block bolts are tight, and IF the bellhousing isn't cracked, then you are back to the original discussion, which led to the torque converter being the most likely problem.

So I go for it in whatever way you decide. I'd at least give Phoenix a call and tell them just what you told us.
 

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I had a similar problem with the 700R4 in my '57. It turned out that the convertor bolts were a little too small, and the convertor wasn't directly lined up. It was just a fraction of an inch off center, creating a vibration. I changed the bolts and it cleared it right up. :anim_25:

Jason
 

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the TC should center to the crank hub index. Small (unshouldered) bolts would certainly let the TC move - but only rotationally. If changing (or just recentering) the bolts stops a vibration - the crank index is buggared up. Seen this - and also seen a dial indicator used to get everything back in line and centered. But that's very time consuming and was only done to save from having to replace the crank.

I would bite the bullet and pull the trans. Get a good visual (and measurement) on both the T\C hub and crank index. If they look good change the T/C. It is the only thing on the input shaft with enough diameter to have a drastic balance issue. When apart also check your bell index pins and the coresponding holes in the housing. If these are worn it could be letting the trans sit off centered which moves the TC off center (and could account for the shredding in the prior build).
 

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conv.

Could be in the way u tightened the conv. Tighten a little @ a time & rotate after each one is snuged untill all are tight.
 

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Discussion Starter · #14 ·
Problem solved...
So I originally purchased my trans from Phoneix Transmisions. Greg, who sold me trans was very nice and I was happy w/my decision. Fast forward about 30 months and my trans was filled with metal shavings. Not really sure the cause, but Greg and Scott at Phoenix told me to send it there and they would take a look. Greg told me all it would cost was shipping. After getting my trans back w/convertor, there was no charge at all. Not even shipping. I was so pleased, as I was a few months past the 2yr warr period. Anyone else could, or would, have told me to pound salt.
After putting it in, I had this vibration that started. Thought it may be frt wheel bearings, pinion angle etc. However, all I did was change the trans, After a few questions here, I rotated the converter by changing the bolt holes, but still there. I discovered the vib was in Park at 2400 rms, BAD. I guess when driving it was magnified. So, I finally disconnetcted the convertor from flywheel and bungied it to trans. I started the car, and no vib!
Called Scott at Phoenix, and without me asking, he sent a new convertor to me...
Bolted it in the weekend, and PERFECT! Its so smooth I cant believe it.
Thabjs to the Scott and Greg at Phoenix Transmissions for such amazing cust service!

Now I need to tackle other issues. Thanks all...
Phil
 

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There responce was better than most for sure.....Too bad the parts were bad to begin with.....Caused a lot of work for you in the long run.
 

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700 trans mission vibration

Working on a 57 283 that was converted to the700 r. I have a vibration from about 2000RPM up parked. I unbolted the converter but it won't slide back. When I turn it by hand it skufs on the fly wheel. I don.t dare start it. The high spots, or bolt hole bosses face the converter. Is this right or could the flywheel have been installed wrong side out?
 

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700 vibration

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Working on a 57 283 that was converted to the700 r. I have a vibration from about 2000RPM up parked. I unbolted the converter but it won't slide back. When I turn it by hand it skufs on the fly wheel. I don.t dare start it. The high spots, or bolt hole bosses face the converter. Is this right or could the flywheel have been installed wrong side out?
 

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Trifive Automotive Electrical Wiring Expert
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Working on a 57 283 that was converted to the700 r. I have a vibration from about 2000RPM up parked. I unbolted the converter but it won't slide back. When I turn it by hand it skufs on the fly wheel. I don.t dare start it. The high spots, or bolt hole bosses face the converter. Is this right or could the flywheel have been installed wrong side out?
It sounds like the converter is not seated all the way in the transmission.
 

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"It sounds like the converter is not seated all the way in the transmission."

That's something that can't practically happen - if that were the case you either couldn't bolt the transmission to the engine, or the convert would not turn the input shaft.

What I'm saying is that the factory fixed that where this can't really happen.
 
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