Motor Vibration

[THEMADTYPH00N]

About a year ago my boss bought a Typhoon. When he bought the truck, it had what we thought was a driveline vibration. So last week he took it to Roadmaster Transmissions to get it looked at. Fast forward to today. He gets a call saying the vibration is not in the driveline or the transmission. They're guessing that it’s in the motor somewhere. They said they where going to take the trans out and check out the torque converter and flex plate. Does anyone have any guesses as to what this might be? It happens around 2100 rpm then goes away as it revs higher. The vibration DOES happen while its park or neutral. Anyone have any guesses as to what this might be?

 

[Tydriver]

Well assuming its all stock, consider checking the balancer on the front of the motor. Make sure its intact etc. Both the flywheel and the balancer are there to dampen vibrations, there is also a WEIGHT on my flywheel thats in a specific location. With the engines being externally balanced it can cause an issue if the balancer is F-ed or the Flywheel. Roadmaster oughta be able to detect it if the weight fell off or is missing. You may go down and take a look yerself.

 

[ed hess]

if it isnt stock and it wa internally balanced then it should not have a weight on the flexplate.

if someone replaced the dampener and has the wrong one. i.e internal instead of external balance dampner this would make things goofy also.

been there and done that.

ed

 

[DanenGraham]

The flexplate can only go on one way though.

 

[ed hess]

not refering to the direction of the weight.

balancers and flexplates are diffferent for internal vs external balnce motors.

ed

 

[Sy769]

not refering to the direction of the weight.

balancers and flexplates are diffferent for internal vs external balnce motors.

ed

I believe the balancer used on our trucks is for a internally balanced SBC.
The flywheel however is a late model style external balance.

 

[THEMADTYPH00N]

I just made a correction. The vibration does happen while it's in park or neutral. This leads me to believe it is something with the flexplate or balancer. Im sure Roadmaster will be able to tell us if its the flexplate. Thanks for your help guys.

 

[TYPHOOL7]

maybe a bent crossmember/bad angle or somethin, bad tranny mounts or a bad motor mount, as far as the converter and flex plate i dont know about that..

 

[nightdiver]

Yeah i d say its a bad motor mount or a bended rod

 

[Lynn D. Brown]

ed,

One simple thing that can happen on the stock type balancer - it has a central core surrounded by an outer ring. These two pieces are connected by a rubber piece in between the 2. If someone pulls the balancer incorrectly by pulling on the outer ring, these 2 pieces can get misaligned. That's why U need to use the correct puller - one that bolts to the inner core like a steering wheel puller. My $.02

 

[bigtime]

not refering to the direction of the weight.

balancers and flexplates are diffferent for internal vs external balnce motors.

ed

I believe the balancer used on our trucks is for a internally balanced SBC.
The flywheel however is a late model style external balance.

Correct. When GM went to the 1 piece rear seal they made the back of the crank round
as opposed to the added weight they used forever.

Even if the damper outer ring turned it would stay in balance but would reek
havok if you put a timing light on it.

If I was making a guess I would look at the mounts, but hey its just a guess.

 

[just a 6]

I have a engine vibration between 1800-2100 rpm, in gear driving or standing still reving it. I have new crank balancer, the weight is on my flex plate, new motor mounts and a new trans mount. Very enoying i thought of posting to see if anybody else had the same problem but never got to it. More suggestions are welcome