Re: Rough Idle in Drive 1972 Lemans

The Pontiac motor is zero lash. All the rocker nuts should be torqued to 
spec. (ie, tight).

Jeff wrote:

> Ok let me start from the begining.
>
>   Recently my wife's 72 Lemans started popping out of the carburator,
> I traced it down and found a broken rocker on the #2 Exhaust valve. I
> changed it and the pushrod (it was slighty bent but not too bad).
>
>   I then decided to adjust all the valve lash on all the cylinders. I
> used the old rule of putting each cylcinder at full intake open, then
> going to the opposite firing order cylcinder, adjusting the rocker nut
> until the pushrod had no play in it, then turning it down another 1/2
> turn to center the hydraulic lifter.
>
>   The car now runs fine in park and neutral and above 5 mph. HOWEVER,
> when at idle in any gear (Reverse, Drive, Second or Low) it runs rough
> and the engine shakes quite a bit, and every-so-often it feels like
> it's about to die but doesn't. The idle-solonoid is set to 600 rpm in
> gear, the timing at 6 degrees btdc, and the dwell at 30 degrees all
> maufactures sticker specs. The cap and rotor and sparkplugs are all
> new, the wires all have good resistance.
>
>   Is this somehow related to my valve-lash adjusting??? Or is it a
> completely different problem that happened to pop up at the same time?
>  PLEASE HELP!
>
>   Thank you in advance,
>    -Jeff-