Hopefully someone with some experience with Carter/Edelbrock carbs can answer a couple questions.
On my GTX I rebuilt the #1412 800 cfm carb earlier in the year and it was running really well until recently when it developed an off-idle stumble. I pulled the carb off this morning to look it over and when I worked the throttle I got nothing from the accelerator pump squirters. I pulled the top and looked at the plunger and all that was there was the plastic tan holder and shaft and no plunger seal. First thought was crud, how did I forget that in the rebuild and then I realized it had been running good until recently and that would not have been the case without the umbrella cup installed. When I pulled out the spring and looked in the bottom of the well, the blue rubber/neoprene/whatever(?) umbrella cup was lodged down in the very bottom. Pulled it out stuck it back on the plunger and under the 4 fingers and it's running like a champ again.
Anyone had a problem with these accelerator pump cups coming off the plunger before? Is there a better accelerator pump umbrella seal to use? I used an Edelbrock rebuild kit from Summit.
Also, all the instructions say to set the accelerator plunger with the idle speed screw backed out, to where the top of the shaft is 13/32 inch above the top of the carb top. That's about where mine would be if I put the rod in the middle hole but the Edelbrock instructions call for the rod to be in the top hole on the #1412 - which would result in maximum stroke for big engines. That puts the top of the shaft way above 13/32 inch on mine. Can anybody think of a reason I should bend the rod link to lower the plunger to this dimension? It seems all it would do is possibly shorter overall plunger travel. There's no delay in pump response.
Possibly there is some connection with the seal coming off and this high setting???
On my GTX I rebuilt the #1412 800 cfm carb earlier in the year and it was running really well until recently when it developed an off-idle stumble. I pulled the carb off this morning to look it over and when I worked the throttle I got nothing from the accelerator pump squirters. I pulled the top and looked at the plunger and all that was there was the plastic tan holder and shaft and no plunger seal. First thought was crud, how did I forget that in the rebuild and then I realized it had been running good until recently and that would not have been the case without the umbrella cup installed. When I pulled out the spring and looked in the bottom of the well, the blue rubber/neoprene/whatever(?) umbrella cup was lodged down in the very bottom. Pulled it out stuck it back on the plunger and under the 4 fingers and it's running like a champ again.
Anyone had a problem with these accelerator pump cups coming off the plunger before? Is there a better accelerator pump umbrella seal to use? I used an Edelbrock rebuild kit from Summit.
Also, all the instructions say to set the accelerator plunger with the idle speed screw backed out, to where the top of the shaft is 13/32 inch above the top of the carb top. That's about where mine would be if I put the rod in the middle hole but the Edelbrock instructions call for the rod to be in the top hole on the #1412 - which would result in maximum stroke for big engines. That puts the top of the shaft way above 13/32 inch on mine. Can anybody think of a reason I should bend the rod link to lower the plunger to this dimension? It seems all it would do is possibly shorter overall plunger travel. There's no delay in pump response.
Possibly there is some connection with the seal coming off and this high setting???
