B carb fuel starvation

[johnbuckley]

Friend sent me this B carb to check over ( it is fitted to a stock A engine with gravity feed tank) - All the symptoms he describes (stalling/stuttering when trying to power up hill etc )point to fuel starvation. Fuel level is 5/8 inch below gasket
No surge baffle with the float (has it been removed or are some like that?}Is the baffle essential?
Fow rates test out ( ml/min at 36 inch): main 88, cap 390, comp 158, power 35. Biggars book recommends, main 136-142, cap 372-462, comp 110-118, power 110-118. I don't want to take all the airway plugs out- the carb looks very clean. Apart from some of the jets being obviously way out are any other things I should be aware of?
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[Chuck Sea/Tac]

Your starving fuel because of a plugged main jet. Get them all to specs first. Check your throttle shaft for wear.

[Jim Brierley]

Also check the ignition, many carb are actually ignition problems.

[tbirdtbird]

has he opened the GAV more.....it is there to play with....many fuel starvation issues are because the GAV is turned in too far....don't be afraid of it

[johnbuckley]

Chuck Sea, the throttle shaft certainly has some play. I find the A carb is fairly forgiving with throttle shaft wear... But is it more critical on the B carb? Would this play cause lack of suction up the power jet, with the controlled port leaking?

[Brian T]

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I would get the main and power jet back to Biggars specs, and make sure the tube leading to the throttle shaft is clear, the B carb doesn't need the GAV after warmup which eliminates that, I don't believe the throttle shaft is a problem, should you need one they are now available

[Ron in Quincy]

Make sure the small hole in the throat or passage way , where the fuel from the pickup tube exits when the throttle is opened, is not plugged.

Ron

[Jacksonlll]

I don't know anything about a B carb, but if the fuel line goes in too far, like it can on an A carb, and hits the screen in the carb, this is exactly what happens. A little circumcision of the tube will fix it.

[Ron in Quincy]

The 32 B and 33-34 C passage ways and throat is no way like the Zenith- or Holley Carburetors that came on the A.

Ron

[George Miller]

check to see what color the spark is and how far it jumps.