[T3] Irregular Idle....again...

[J. Jonik]

A while back, the 71 (73 engine) (Std FI) had idling problems but also gas spitting out the tail pipe and stalling, starting problems, and so forth.   Finally corrected that "Endless Fuel Problem", at the end, with changed temp sensor, unhooking cold start stuff, and replacing the brain box...and some repair of not so good-looking wires.  

Now I have a 73 engine (thrust bearing in 72 case was shot) that runs and sounds great. Made two long round trips to Connecticut (from Philly) with heavy weight aboard on return trips.   Nothing like test-runs on G. Washington Bridge.
Not even a hint of a problem....EXCEPT a little oddness a couple of times.  Turned out that the distributor mounting stud was loose...so distributor had a little play  Temporarily snugged it up and re-did the stud when back home.

  But, now (coincidental with that stud job?) the idle is kind of like someone's sending Morse Code messages with little pushes on the throttle.   No backfires.  It's a frequent, regular up and down, not slowly up then down.  When revved just a bit, or a lot, no irregularity is evident.  Engine sounds great otherwise, and starts very easily.

[ Had to interrupt the search for that problem when it became clear that the oil cooler seals had to be changed.  That's done, everything reconnected.  Same old idling problem though. ]

-Changed Pressure Regulator, twice, with good spares.  No difference to speak of.   A little, but hard to tell.
- Cleaned spark plugs.
- Cleaned and messed with distributor...different points, different condenser, different
distributor body itself, and different trigger contacts.   Vacuum adv. passes the suction test      No difference noted.
- Hose from AAR to Air Distributor was loose.  Ah Ha!   Trimmed both ratty ends a little and re-installed tightly.   No difference noted re/ idle..
- Put hose clamps on those fat manifold hose sections.  Maybe a percent better, but not a fix.

Have not, yet, removed and cleaned, or changed, the AAR....but screws and nuts are tight.    Still can't find info on how to adjust that little set screw inside.

I can't find the year or so old raps here about Irregular Idle.  I need a reminder about What Are the Most Likely Suspects that might cause this.

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