Thread: Need some timing advice

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Originally posted by DennyW
I'm working on the other info. What I saw, or seems to be off is, I see you have manual chokes. It looks like from the picture that on the secondary carb, the choke arm appears to be on some. What you want to do for plain old mechanical checks is this. This is all done without the engine running.
Take off the air stacks
Unhook the linkage going from the front carb to the back carb while paying attention to see if the throttle moves on either carb. (rod length could be off)
Next, take off the linkage on the secondary carb that goes to the throttle inside. Also while watching to see if the throttle moves closed.
One carb at a time, turn the idle screw counter clockwise until lose. If you move the throttle you should be able to detect a slight stickyness because the throttle plates should close all the way. If so, thats good. Now turn the screw clockwise, just until you no longer feel the throttle plates sticking. Do that on both carbs.
You also want to make a visual check to make sure the secondary throttle plates are closed. If the vacuum diaphram linkage is sticking, this could be holding the secondary throttle plates open enough to up the idle. (the adjustment for the base idle is on the underside). (pictures will be coming on this)
Float levels, with the side sight screws out, not running right at this point, the fuel should be right at the bottom of the threads, or slightly lower because the engine is cool. If you shake the boat, the fuel should just wet the threads.
Air adjustment, turn clockwise, and lightly seat them, turn counter clockwise, 1 turn, both carbs, all idle air mix screws. By this time, you should have found something wrong.
When you go to put the linkage back in for the front to back carbs, it should fit without moving the throttle lever. (O fit).
Now, check the throttle linkage from the inside to the secondary carb, that should also fit with a O fit. Without moving anything. Let me know from this point.

Thanks for the great post.. here is what i have done..

1:undid the thottle linakge that concts both carbs together.. zero movement the throttle plates didnt move and are closed . So i think rod linkage is proper length

2: idle screws: ok i already had those back out as far as they can go ( counter clock wise) they are not touching anything... so again the main throttle plates are closed ...

3: idle air screws.. Had them at 1.5 turns out but i will do the 1 turn out.

4: float level.. is good.. fuel just dribbles out

5:OK to the secondary throttle plates: ( which i think is the problem). they are slightly open. i can close them by hand but they spring back open. I backed out the screw from the under side but it wasnt touching the plates even befor i backed them out ( is it a slotten screw ) to adjust them but they still remain slghtly open. .

It seems as though as something is keeping the secondary throttle plates in the slightly open postition.. I think that is what is causing the fast idle. ..

again you are a great help and i am learing a ton from this.. let me know waht you think

Chris



EDIT:: here take a look at this any maybe it will clear it up for you on the secondaries throttel plates
http://www.clubhotrod.com/photopost/...php?photo=6468