Throttle Stop Springs???

[Drumagician]

Ok, I decided to take my carbs off and and play with the butterfly adjuster screws to see how they all effected each other when looking right at them. Well conventioanl syncronization theory says that you adjust 1 to 2, which means that 2 should not change. then you adjust 4 to 3 which means that 4 does not change. Then you adjust 1&2 to 3&4 which means 3&4 should not change. [B]---#3 is the master---[B] When I started making random adjustments I noticed that for example, when adjusting 4 to 3, I saw 1 & 2 moving. My #3 would not go full closed because the other carbs were keeping it open. This should not be because assuming #3 can close completely, it should stay that way at all times (also assuming the idle stop is backed off). Upon futher investigation, I concluded that the throttle stop springs (bottom most spring of the assembly used to keep pressure on the adjuster screw so vibration won't make them back out) were pushing the butterfly open. Anyway, I was able to finally get the screws set so that all valves were full closed but it took a while and seemed like a damn puzzle. Now I am a little skeptical about the function of the system. I don't know how I would be able to get a good sync like this even though I have in the past. Any thoughts??

[CatatonicBug]

You have to realize that there is no "Master". Syncronizing the carbs is simply adjusting them in relation to each other. When you turn the screw between 1&2, BOTH carbs move - One goes up while the other goes down. The same is true for the screw between 3&4. Then, the screw between 2&3 adjusts the 2 sides (2 carbs at a time) in relation to each other.

[fredintoon]

You have to realize that there is no "Master".- - -

Hi 'Bug,
#3 is the master in the sense that #3 is the carb that the throttle stop screw and the throttle cable work directly.
Thus the other carbs openings get adjusted relative to #3.

[DGXSER]

Yep, #3 butterfly throttle plate only responds to the throttle cable.

So when you adjust the screw between #3 and #4, your bringing 4 into "line" with 3. In my experiences to date, it shows that #1 is adjusted to be in "line" with #2 when you adjust the screw between those two. The screw between #2 and #3 brings the set of #1 and #2 in line with #3 and #4 setting.

So in theory, if #3 has 8" vacuum then your adjusting #4 to that 8". If #2 shows 6" vacuum your adjusting #1 to 6". Then finally, your bringing the set of #1 and #2 up to 8" of vacuum so they all match #3.

In reality, every adjustment you make effects the entire engine, so those numbers do not stay quite that consistant.