Mercarb Y38 Carb rebuild

[cdelong]

My 1993 3.0 liter Merc has a stumble off idle. I did a tune up and replaced all the ignition components... cap, rotor, wires, plugs and set the timing.

It still had the stumble so I started looking at the carb.... it has virtually no pump shot for the first 1" of throttle arm travel. I guess a rebuild is in order... the diaphragm is probably shot.

I noticed the arm for the accellerator pump is in the middle hole. Moving it to the farthest hole on the arm would give the pump a quicker reaction... should I try that as well while the carb is off?

It is a 2BBL Mercarb Y38 with an electric choke, side inlet, one idle mixture screw and says 15396A-4 on the body.

[cdelong]

Got her all rebuilt. I'll slap it on after work today and see how the pump shot is. The diaphragm feels real tight now and the carb is all set back to factory specs.

She should stand on the bumper now!! All those days of drag racing paid off..... I rebuilt way too many carbs to count.

[cdelong]

Pump shot is like new..... the diaphragm was shot causing the low speed hesitation.