grinding noise

[RIPPEDK5]

I have a grinding noise when i run my 355. This noise is heard every few seconds. It just started yesterday.. Motor is very new, tranny is very new, both with no actual miles on them. Have been running on and off for approx. 3-4 hours worth total time over the last month. no problems then. Base timing is set at 8 degrees BTDC. Motor builder says its a torque converter problem? But why would it just all of a sudden make grinding noise... Kinda like run, run, run, Grind, run, run, run, grind, run, grind (the sound its making sounds very similar to when you engage a starter while the truck is still running but less loud)

any ideas,

and also why would a motor run so rough that it wants to rip the mounts off the frame (lots of movement in the motor) and i know its at 8 degrees.. Carb?

 

[mstockton]

Not sure about the roughness of the engine, and if its an automatic, are you sure the flex plate was installed facing the correct way? If its not, it can screw with the TQ conv, my buddy had that problem when he had his engine rebuilt, went around and around with the builder and tranny shop and after 3 weeks they figured it out...

Thats the only idea I've got without knowing more..

-Martin

 

[RIPPEDK5]

Funny thing is; I just started my truck up again and the noise wasnt there...Its intermitent...That sucks..... Maybe starter is just slightly engaged? or not kicking out far enough?