Hey all, please forgive me if this is off the chart ignorant but don’t have any experience with Maverick carburetors. Attached is the pics of the one on my daughters 77. Engine is a 250 with an auto transmission and factory air. It runs like a champ however it has a slight hesitation on acceleration and my wife is afraid she will get creamed trying to enter the interstate. I believe it is a YF-A but not a hundred percent and not exactly sure how to adjust it. Figured I would try here before Google. Any help would be greatly appreciated. Mark
Mavdad I have 0 experience with your carb type. I,ve fiddled with 2 barrel 2100's and 4 barrels holleys. Before assuming its your carb. How,s your tune on car? If its been awhile fresh plugs, wires, cap, rotor, points, yada yada?
Looks to be a fairly recent replacement, likely a rebuilt unit. Two things #1.. is the flexable hot air pickup attached to air cleaner snorkle? Carbs of this era were very lean, often if missing, hesitation is a problem. #2 with air cleaner removed & engine off. Look down into carb and slowly open throttle, does the carb pump shoot a small stream of gas? If not, does it squirt at a more rapid opening? If this test fails, there is a internal issue inside carb. #3(OK I lied about two things). Distributor, is timing correct? Does it have the dual timing advance/retard vac advance diaphragm? If so remove retard line(one closest to dist cap), plug it with a screw, nail anything that will fit snugly. Test drive. Retarded timing at tip in(opening throttle) is notorious for causing hesitation. #4 Idle mixture, is it at optimum? Basically means adjusted for max amount of vacuum(timing should checked prior). Generally higher the vacuum, the less likely there will be hesitation.
My two Cents ,the Dist .vacuum Advance ,If single Hose, gets only a building Vacuum. Not a Constant Vacuum! It builds with Acceleration
Your 250 with the Carter YFA looks amazingly clean. As mentioned , hesitation can be Fuel related or Ignition related (or both!). Don't believe you mentioned if it ignition is Points' or DSII electronic ignition . Hesitation can be a symptom of carbs' faulty accelerator pump or incorrect float level . Not much other 'adjustment' on modern carbs, the Carb' if problematic may simply need a 'rebuild kit' or may be a continued learning curve... . Typically a good tuneup starting with Plugs, maybe wires and Dist. Cap and timing close to spec will eliminate ignition issues. Timing light should reveal any spark oddities. have fun 'Universal Replacement' type carbs are widely available fairly inexpensively as a last resort but look seriously at simple solutions first ... https://www.ebay.com/itm/Carburetor...659176?hash=item340d132a28:g:h00AAOSwMdddCezz .