<VV> Trouble with idle back & PG question

[Dennis & Debbie Pleau]

On an automatic car, always set the idle with the air cleaners on.

dp

At 06:53 PM 11/12/2005, Padgett wrote:
>Spent another fruitless hour that wound up with extraction of my aunchient 
>Heathkit  ignition analyzer from the Sun DT-680 it has been sitting on for 
>the last decade.  Fired it up after resetting everything including 
>drilling the orifice in the PCV tube out to 1/16 (book says 5/64" but 1/16 
>was all I could  do by spinning the drill in my fingers). Smoke at idle 
>mostly disappeared but get puffs when revved.
>
>Shot of the ignition scope with engine at idle (without flash so several 
>ignition pulses showing a little scatter) is at
>http://padgett.ws/files/analyzer.jpg
>
>Hokay, Unisys says carbs are balanced at 800 and 1500 rpm.  Idle in N at 
>800 rpm is stable and smooth. 1/2 turn richer idle mixture from rpm drop.
>
>Put in drive and drops to about 500 rpm. Only stays there for a few 
>seconds before misfiring begins (timing light stops flashing). A "loose 
>timing chain" rattle occurs (detonation ?) and the engine stalls. 
>Theremocouples on #2 and #5 plugs are reading 240F with 80F ambient.
>
>So question: is a 300 rpm drop when PG is put in gear at 800 rpm normal ? 
>If the rattle is detonation, why (8 degrees initial and pretty much all 93 
>octane now) ?
>
>Did have a couple of weeks when it would idle, then went downhill. Seems 
>to be a history of doing that with this car. Suppose should pull carbs off 
>again and check all passages (are 66 -024s with PE and 50 jets. Is going 
>to 52 jets advised while open ?)
>
>Seemed to be very little sediment in gas tank when pulled the sender. 
>Note: ran best with almost no gas in tank, ok with 1/2, most cranky after 
>put another 6 gallons of 93 in this morning. Not enough of a sample to 
>know if related but may be an indicator.
>
>Note: is quite cold blooded even with chokes full closed & 70-80 degree 
>start, as soon as pull-off does its thing will stall. Several cycles 
>required before will stay running. Related ?
>
>Things would be a lot simpler if had a good running 110/PG to compare 
>settings & readouts but don't so need to perform a data dump and ask.
>
>Thanks,
>
>Padgett