Generator vibration

[cb5300]

It seems like I have developed a vibration in my generator (Onan 12.5 KW) The output seems to be OK, but it just seems like something is out of balance while it's running. The Cummins shop here has checked it out and agrees and said that they will need to pull the generator and tear it down in order to check it out....
Anybody else out there ever have this problem...I'd like to be able to point the Cummins mechanics in the right direction if possible.

[Twomed]

Onan 10 and 12.5 had a design change on the cooling fan drive. Mine made the big rumble and was fixed under warranty. Call Onan with your serial and specs. Your dealer should know about this.

[JMonroe]

Could it be as simple as a broken motor mount?

[TXiceman]

Motor mount or a loose harmonic damper,


Ken

[cb5300]

Well, it turned out to be a broken motor mount....I guess I got off easy. I haven't gotten the bill yet, but a broken motor mount can't be that bad....