Hi everybody,

I've got an a15 running twin 40mm dellortos. all i was wondering was how the accellerator pump operates on these and what tends to stop them from working. when you open the throttle only one operates so as the car has a mass hesitation on take off. any help would be gladly appreciated.

Thanks,

Patrick.

Hey mate

fist check the pump diaphragm. undo the 4 screws on the bottom of the carb, and check for gunk, splits, broken springs etc.

Make sure the actuator rod for the pump is working, when you open the butterflys, the rod should work the actuator , which should work the diaphragm..

Next, pull out the accel pumps (big screw on top of carbs) and make sure they aint blocked. They are tiny holes, they block easily. If you see gas getting pushed up there when you snap the butterflys open, the diaphragm is ok, the pump jets are blocked!

Dont get tempted to file em out

Just so you know, there are four of these large screws on the top of the carb, the ones to the rear of the carb near the mix screw are the progression holes (#59), you want to check the ones further forward (middle of carb #52) this is where the accelarator pump jet is found

if nothing is blocked this might help.the large screw that there talking about has two holes in it these holes have to line up with the grooves in the top of the pump jet,if they dont the fuel will not flow through the way to fix this is to get new washers or try putting two on.ive been experiencing the same problem its been driving me crazy,good luck