MTFCA Forum

After making all the base line jet adjustments per the book, I swapped out a good running U&J for this freshly rebuilt Winfield S-AA-U, tied the throttle closed, pulled the choke, and pushed the starter button. To my amazement, it near instantaneously popped off and sat there idling at a smooth slow idle! Creepy!

I futzed with the idle mixture... only to return it back to the original adjustment setting (number of detents from closed). So the jam nut was tightened down on the idle stop screw, without adjustment! Creepy!

Cracked the throttle open to a driving range rpm and started twisting the intermediate screw... only to return it back to the original adjustment setting (number of detents from closed). Creepy!

Working on a bell crank to connect the throttle linkage so I can drive it, then will see if the intermediate or high speed jets need additional adjustment. Have never had this happen before... this was too easy!

I had a Schebler FA that was all kinds of cruddy looking, bought off eBay many moons ago, out of the box on to the car, ran great.

Is your base adjustment 16 clicks? I’ve found that you don’t have to deviate much on idle and midrange but the high speed ends up several clicks less.


Andy

Winfield really knew what he was doing

So far, I’m at 2 turns out on each of the intermediate and high speed screws (pretty sure that’s 20 clicks), and 3/4 turn on the idle. It ran pretty smooth down to 1-1/2 turns on the intermediate jet, but would stumble when accelerating so fattened it back up

Was workin on the throttle bell crank, but haven’t made any actual progress, and now have to work out of town for the next couple of days... gotta get back on the road as we have a ~400 mile trip in a couple weeks

The most difficult part of the carb swap was solving the throttle linkage bell crank challenge. I wound up making another carb adapter with built in bosses to support the bell crank. Several simpler ideas were attempted, but ran into clearance issues every time.

Got it on the road today and ran stronger than ever (could be because the carb is noticeably bigger than the U&J), but also idles and pulls under load much smoother. The first drive yielded a slight hesitation during transition off of idle and acceleration. The plugs were kinda sooty, so I leaned out both the intermediate and high speed jets 2 clicks each. Went for a drive this evening, and realized that leaning it out was the wrong thing to do. The hesitation is much worse. Will open the jets 4 clicks before another drive tomorrow...

The old advice was you want a puff of black smoke when you gun the motor. When I ran the small Winfield I had to richen the intermediate and lean the high speed.


Andy

My limited experience with Winfields has been the same as Andy's. More intermediate mixture than high speed.
Red

We spent last week driving 400+ miles around Washington’s Olympic peninsula with the Winfield carb on the ‘15 touring. Never skipped a beat! (Did blow out the muffler tho) The off idle hesitation continued at first, but found the plugs bright white so fattened up the mixture to 2-1/2 turns on both intermediate and high speed circuits. Hesitation is gone, and no noticeable smoke out the tailpipe. We cruised at bout 45, but was able to pull the hills right along with the speedsters in high gear!