Won't idle anymore.....and seems to flood?

[Cliff Ruggles]

If you are sucking fuel from the secondary nozzles at idle the throttle plates or plate isn't well indexed and sealed when they close.  I actually see this quite often and recommend removing it from the main casting and spending some time with it until the plates are well sealed in the bores when closed, no binding, linkage has clearance so it isn't holding them open, etc......

[fussfeld]

i'm still working on it and have not given up (yet).   

Are the primary throttle blades supposed to be completely closed at curb idle/ choke completely open.  Or are they supposed to be cracked just slightly open?

[Cliff Ruggles]

No, they should not be completely closed.  If they are there is a vacuum leak someplace, too much idle bypass air, too much initial timing, or combinations of all three.....

[fussfeld]

i think i am in the direction of having the problem basically solved.  However, i don't want to conclude the thread just yet because of the other problem in the other thread-----can't count the chickens before the eggs hatch kind of deal......

[fussfeld]

i apologize for starting two threads----because i thought the problems were separate, but thinking about it more, they are probably related---very related.

So, i'm finally able at least to get the engine to "idle" at about 800 rpm with no pedal intervention.   

This gives me time to fiddle with the idle mix screws.    However, if it's at 800 long enough, then it kinda gradually dies out.    So, let's say 900 and above it will idle indefinitely.

Where i got to here is, i think when adjusting the secondary plate opening, i inadvertently bent the primary throttle stop tab to where the primary butterflies were  to far closed----thus it would stall out due to lack of air.

i turned the idle screw up a little to where we can "idle" at 900 with no pedal intervention.   

i think the primaries are positioned below the horizontal "slot" in the bores for vac advance.  Because that's how i set it when i had it off the engine.

[fussfeld]

Update 10/28:

Sorry for the delay.

It turns out that some of the valve seats, as well as some valves in the heads were bad.  i had the heads rebuilt:  magnafluxed, boil/steam cleaned (not sure of the correct term?), new valve seats installed, a few new valves installed.

Engine runs better than ever:  Idles in neutral @700, in gear @500-600.  Normal for once....

BTW,  Malcolm Durham's SuperCar Automotive did  the work;   Just out of sheer chance and for non-automotive reasons, about a month ago, i bumped into Don Durham-----who i learned is Malcolm Durham's brother.   Don now runs the shop.

But that sheer chance meeting gave me the idea to get them to fix the problem.  Who better to fix it?

i apologize for blaming the carb.  It had nothing to do with it.