damper spun?
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
damper spun?
I think my elastomeric damper might have spun/twisted,, its off by 2 degrees.
Its an external balance hub so I would imagine that 2-degrees is enough to give me the vibration that I have from 3200rpm up.
Any experience here?
Its an external balance hub so I would imagine that 2-degrees is enough to give me the vibration that I have from 3200rpm up.
Any experience here?
Safety Car
Joined: Nov 2004
Posts: 4,991
Likes: 5
From: The Pines South Jersey
my tpi had 109k on it and I didnt notice any wear to the damper while the motor was in the car - on the stand I can believe how lucky I was
Its cheap insurance if anything, change it out if you have miles on the car
Its cheap insurance if anything, change it out if you have miles on the car
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Any way to know if it was always like that or no?
If you decide to get another damper,mark the lines to hub with some paint,so if it ever moves you will KNOW it did.
I didnt know if you had posted about a vibration before,but has it always done this since new motor install and break in?
Did you take the belt off to see if the vibe was still there?Is exhaust too close to the floorpan and vibrating the car?Motor mounts tight and good?
Just simple stuff to check...dont know what you checked since then...I had a similar problem years ago and the exhaust was a main factor,but didnt solve the problem.
A new balancer fixed it...it was off a little bit but I didnt think it was at first.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
I bought a new damper and they dont match up, so using the new one as a guide, I see that the old one is off by @ 2 degees.
I have checked everyting else I can check since last August, so its not an obvious problem
I have checked everyting else I can check since last August, so its not an obvious problem
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
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Team Owner
Joined: Jul 2002
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From: The light that never warms.
St. Jude Donor '12
The one on my LT1 in the Impala started letting go at about 95K. It wasn't completely loose, but it had a LOT of play in it, so much that the belt was really making a racket. Luckily, the LT1 isn't too difficult to R&R. I think I did use a steering wheel puller to get it off, but the new one just bolted up.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
It wasnt the damper, I put a new damper on it and the vibe was still there,
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
Safety Car
Joined: Jan 2006
Posts: 3,566
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From: Mt Laurel NJ
St. Jude Donor '06-'07
It wasnt the damper, I put a new damper on it and the vibe was still there,
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
Except when you rebuild a motor you can make more power...you just spend money with a tranny rebuild... 
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
[QUOTE=USAsOnlyWay;1565779029
So do you remember if it vibed with the clutch in?
Thanks for the PM.[/QUOTE]
Clutch engaged, clutch in Nuetral, Clutch depressed, same vibe same rpm each time.
I will have the tranny put back in the car by tomorrow @ noon, fingers crossed
So do you remember if it vibed with the clutch in?
Thanks for the PM.[/QUOTE]
Clutch engaged, clutch in Nuetral, Clutch depressed, same vibe same rpm each time.
I will have the tranny put back in the car by tomorrow @ noon, fingers crossed
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
And the verdict is...................................... ................
Bad Pilot Bearing
Emotionally, I fee like all of the above!
I had put a new needle bearing into the crank, but since I had put a
.150" spacer between the BH & Block.
So this time, I put an Extended "extra long" Pilot Bushing into take up the spacer difference.
Bad Pilot Bearing
Emotionally, I fee like all of the above!
I had put a new needle bearing into the crank, but since I had put a
.150" spacer between the BH & Block.
So this time, I put an Extended "extra long" Pilot Bushing into take up the spacer difference.
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Very interesting. Glad you got it resolved. What a pain though, didn't know a pilot bearing could cause these issues. So you ended up using the bearing with the needle bearings or a bronze bushing?
Currently I have a normal bushing in the car. Maybe I'll try swapping the damper still. Very interesting, thanks for the update.
Currently I have a normal bushing in the car. Maybe I'll try swapping the damper still. Very interesting, thanks for the update.
Intermediate
Joined: May 2008
Posts: 36
Likes: 0
From: Katy TX
It wasnt the damper, I put a new damper on it and the vibe was still there,
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
So I pulled the tranny again and fired the engine with no Pressure plate or clutch and the vivbe is gone.
The Flywheel and PP were checked on the engine balancer by the machine shop and are perfect, so it has to be the pilot bearing or the tranny.
The needle bearing was a little loose so I put a new Pilot Bronze Bushing in and will fire it up on Saturday, if that does not fix it, then it is the tranny
Have you considered that your pressure plate may be out of balance?
A transmission rarely gives you engine vibrations, but a pressure plate can.
Just food for thought.