Dual Dominator Blower carb Accellerator pump tuning/linkage adjustment
02-16-2017, 07:47 AM
#2
So, in the process of putting my upper ends back together last year, I noticed a lot of differences between the engines on linkage adjustments and also on accelerator pump adjustments. One would think someone put these setups together on a bench next to each other and would have made the setups identical, does not look like that happened or they have been thoroughly molested over time.
So to start with, the throttle cable is mounted on a hacked up spacer, and there is a tap broke off in the bracket that mounts to the blower
. Where the cable connects to the first part of the actuating linkage, the angles of that linkage on the spline shaft are different from motor to motor. Also, the all the linkage rods adjust opposite from side to side, I swear I am not OCD but this **** drives me crazy. What I adjust clockwise on one set of carbs it is opposite on the other. I swear, none of them match, I am pretty sure a 10yr old set these up. I can flip the rods around so they all match easy enough, just takes a little time. My real question is, how do I set up the lever arms on the hex shafts? They are at all different angles from motor to motor, maybe pick the motor that runs better and adjust the other on to match?
This leads to my next question on accelerator pump accelerator pump adjustment. Obviously I am not a carb tuning expert but I thought the accelerator pump arm should be adjusted so it is almost touching the pump? These things were all over the place, from 1/16" to over 1/8" away from the pumps. I adjusted them all up to almost touching the pumps. One motor seemed to run fine on take off the other seemed to fall on its face if I gave it too much throttle trying to plane off. How should the pumps be adjusted?
So, I am thinking the linkage arm adjustment from motor to motor is also part of the one motor falling on its face. Any input welcome here.
[ATTACH=CONFIG]564831[/ATTACH]
So to start with, the throttle cable is mounted on a hacked up spacer, and there is a tap broke off in the bracket that mounts to the blower
. Where the cable connects to the first part of the actuating linkage, the angles of that linkage on the spline shaft are different from motor to motor. Also, the all the linkage rods adjust opposite from side to side, I swear I am not OCD but this **** drives me crazy. What I adjust clockwise on one set of carbs it is opposite on the other. I swear, none of them match, I am pretty sure a 10yr old set these up. I can flip the rods around so they all match easy enough, just takes a little time. My real question is, how do I set up the lever arms on the hex shafts? They are at all different angles from motor to motor, maybe pick the motor that runs better and adjust the other on to match?This leads to my next question on accelerator pump accelerator pump adjustment. Obviously I am not a carb tuning expert but I thought the accelerator pump arm should be adjusted so it is almost touching the pump? These things were all over the place, from 1/16" to over 1/8" away from the pumps. I adjusted them all up to almost touching the pumps. One motor seemed to run fine on take off the other seemed to fall on its face if I gave it too much throttle trying to plane off. How should the pumps be adjusted?
So, I am thinking the linkage arm adjustment from motor to motor is also part of the one motor falling on its face. Any input welcome here.
[ATTACH=CONFIG]564831[/ATTACH]
02-16-2017, 09:14 AM
#3
Registered
You have to have the pump start as soon as the throttle moves. The only clearance you need is when the throttle is wide open you don't bind the pump arm. Sometimes you have to bend the pump arm or file on the cam. Dominators can be hard with the internal linkage.
02-24-2017, 07:35 PM
#8
02-25-2017, 05:52 AM
#9
Here is what I was going to copy for fuel lines.
[ATTACH=CONFIG]565039[/ATTACH]
