Been there, done that and the idle arm bushings were shot.

It may be a worn trailing arm bushing but, since there's no directional control problems encountered when accelerating or decelerating, I'd be surprised to find them bad. Even a slight amount of wear in a trailing arm bushing will make a 123 feel totally unmanageable when under hard acceleration. Beleive me, you don't want it to be a trailing arm bushing. That job is a gin-yoo-wine PITA!

Idle arm bushings sometimes see premature wear if the cyclone oil separator in the air filter housing is leaking or, if the separator drain is leaking...it drips right onto the bushings.

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Never a dull moment at Berry Hill Farm.