[Schurkey]

Originally Posted by srmmmm

What's the best way of getting the epoxy off to access the scree again?

Why is there epoxy over the screw?

[steve25]

The epoxy was put there over that hole so no one would mess with that adjustment.

If you must fiddle with it the only way to do the job right is to remove the carb, flip it upside down and drain the carb 100% and then drill it out while upside down while someone holds a vacuum close by .

It’s best to use a battery powered drill just in case there’s any gas fumes left around that could be set off with a electric drill.

If you mess with it be sure to use the stick end of a hand held caliper to note the measure you started at so you can get back to is if need be.

[Kenth]

Originally Posted by srmmmm

I did discover I can close the idle mixture screws all the way and the engine still idles, so the APT must have been "adjusted" and the true possible cause of the remaining issues.

It is not entierly impossible that your engine runs on the off-idle slots when the idle needles are seated, or are they?

Maybe the springs are long enough to stop the needles before they hit bottom and closes off the holes?
Remove the springs and seat the needles, does it still runs?

And, adjusting the APT will do NOTHING for the idle needles position, the idle circuit is a separate stand alone circuit.

FWIW

[srmmmm]

Originally Posted by Kenth

It is not entierly impossible that your engine runs on the off-idle slots when the idle needles are seated, or are they?

Maybe the springs are long enough to stop the needles before they hit bottom and closes off the holes?
Remove the springs and seat the needles, does it still runs?

And, adjusting the APT will do NOTHING for the idle needles position, the idle circuit is a separate stand alone circuit.

FWIW

I'll pull the springs off and try. I do already see the tips of the needles protruding into the barrels right now. But I had thought the height of the power piston was possibly altered by the carb rebuilder to allow more fuel to be available to the idle circuit and transfer slots in anticipation of the cam I was running.

[srmmmm]

Originally Posted by Schurkey

Why is there epoxy over the screw?

I suspect the carb rebuilder altered the setting as part of his "Stage II" level option taking into account my engine/cam specification, and epoxied over the opening.

[steve25]

None the less turning the idle mixture screws all the way in should kill the motor at idle.

[Kenth]

Originally Posted by steve25

None the less turning the idle mixture screws all the way in should kill the motor at idle.

Depends on the length of the off-idle slots and how far they are under the closed throttle blades. Not all Qjets are the same in that regard, f.e. look at the Chevy M4 units.

[Kenth]

Originally Posted by srmmmm

I'll pull the springs off and try. I do already see the tips of the needles protruding into the barrels right now. But I had thought the height of the power piston was possibly altered by the carb rebuilder to allow more fuel to be available to the idle circuit and transfer slots in anticipation of the cam I was running.

The square area between jets and rods will always be larger than the square area of the idle tube restrictions, thus it wont matter how you adjust the APT.
As said before, the idle circuit is stand alone circuit.

[steve25]

So with the motor at a fully hot idle if you close off the choke slowly what happens?