Hello Guys

On the "New D4 on the Farm" thread a reference to Ag-Mike's "finding the secret of pony carbs" was mentioned - can Ag-Mike or someone explain what this is, despite searches I can find what it might be (and believe me, I need every secret I can get about pony carbs)

Cheers - Foster

Foster, Ag-Mike found that on one of the adjustment screws (I Don't remember which one) seems that if the screw was at one time over-tightened, it would deform the seat (?) upon which it bears and cause the carb to run out of adjustment no matter what you did to fine tune it. I scanned some pictures of the part and adjustment, but those images are stored on another computer that continues to crash on me. I will try to retrieve them, but in the meantime, I bet Ag-Mike will post a reply.

There may be more than "one" but I believe Ag-Mikes secret had to do with checking the bell crank (lever) in the bowl cover to make sure it was at 90 degrees and not bent from over tightening. If it is bent it throws off the mixture adjustment giving a lean adjustment.

the bell crank needs tobe at 90 degrees. the hi side (i think) adjustmest screw in contact with it will bend it pass 90. one will see the original divet made by the screw and other later marks maybe too. mine wouldn't run without choke after rebuild, i remembered the different marks on the bell crank and noted it wasn't 90 during rebuild. so i took it off and rebent it back to 90 and readjusted the setting. runs fine and choke isn't needed to keep it running. its kinda hard to get to these parts. if memory is correct one has to drive out a keeper pin to get it apart. good luck.

thanks om for keeping the pics, mine are on 3 harddrives back.

Is there anything special about the adj. screw, as mine has a machine screw with a nut to lock the setting?? My pony seems to run rich adj. the screw either way doesn't seem to change anything:confused: OM do you happen to know the zenith model on a D4 6U444 ? Would anyone have the part in the photos that OM posted for sale ? Thanks for your time, quinq

Nothing special about the adjusting screw for the main jet horizontal adjustment as long as you have a matched thread.
Appears to be two carb candidates for the early 6U
Lists a Cat # 5F3528/Zenith #10367 for the D4
and a Cat # 5F3530/Zenith #10365 for D2/D4
Both are basic TU4C Zenith models.

Clogged passages in the carb and air intake filter are the most common cause of running rich. Also a high float level.

Just serviced the air cleaner, had the carb apart, passages appeared to be clear. OM do you have the float setting? Maybe I can ck that next. Thanks again, quinq

Float topic was just covered a couple of days ago.
www.acmoc.org/ACMOC_BB/showthread.php?t=950