Engine vibration

[sdstang]

I have a vibration in my engine or trans. I installed a new trans converter and flex plate. I get a nasty vibration from 1400 to 1800 RPMs. I pulled to cover off and made two videos I added to my photo bucket. Can any on tell me if this might be the issue. Seems the flex plate is oscillating  about 1/8 plus. Sorry for all the bouncing around.

http://s172.photobucket.com/user/jharness/library/?sort=3&page=1

 

[sdstang]

I have a vibration in my engine or trans. I installed a new trans converter and flex plate. I get a nasty vibration from 1400 to 1800 RPMs. I pulled to cover off and made two videos I added to my photo bucket. Can any on tell me if this might be the issue. Seems the flex plate is oscillating  about 1/8 plus. Sorry for all the bouncing around.

http://s172.photobucket.com/user/jharness/library/?sort=3&page=1

Any thoughts?

 

[73pony]

What counter weight did you get on the flex plate? Should be 28 oz if it is a 351c.

 

[Bentworker]

Doh! Somewhere there has to be a reference that spells out runout on a flex plate. That video makes it look like you have at least .100"

 

[Pastel Blue]

On my recent engine rebuild, the flexplate was part of the overall running assembly balancing, which required some additional weight to be added to the flexplate in order to  bring the entire rotating assembly in line. Guess that will make for some fun if I need to change out the flexplate in the future... You can definitely see the movement in your setup. Was something not true when installed? I guess because they are new does not guarantee perfect operation from the get go. That is a PIA you got there...

 

[sdstang]

What counter weight did you get on the flex plate? Should be 28 oz if it is a 351c.

I used my old FMX flex plate which was mated to my 351 cleveland.

-Jim

 

[Don C]

What engine, what transmission, what's new and what's being re-used?