Hi, new to the forum and PWC (multi cylinder engines) although I've been a mechanic on bikes and quads for years.
I have a newly rebuilt motor that was just broke-in and it seems to run great from bottom to top. Plug readings are identical tan to light brown.
However I want to make sure my jetting is right for safety reasons and best performance as I'm new to PWC and multi cylinder engines.
My needles are set at service manual spec but boyesen suggests this -
I put boyesen reeds in this motor and an instruction pack came with them giving some really good straight forward instructions on how to tune these mikuni carbs. Although it is talking a bout a single carb it states the same basic procedure for multi carb set-ups. I guess just adjust them all identically.
It says, have the boat in the water warmed up on the trailer and at idle turn the L/S needle IN/OUT from factory setting till the motor revs to it's highest and if you go to far then it will start to fall off. at that point go back to where it's revving to it's highest and leave it there. obviously do this with 3 carbs and try to get them even.
Then, run it and come to the dock and go to the H/S needle and turn it 1/2 turn out or richer and run it. If it runs worse then go the other direction or vise-versa etc.... Once you've found the optimum power, turn out 1/4 turn and your good.
Does this sound like a good way to tune to you?
I have a newly rebuilt motor that was just broke-in and it seems to run great from bottom to top. Plug readings are identical tan to light brown.
However I want to make sure my jetting is right for safety reasons and best performance as I'm new to PWC and multi cylinder engines.
My needles are set at service manual spec but boyesen suggests this -
I put boyesen reeds in this motor and an instruction pack came with them giving some really good straight forward instructions on how to tune these mikuni carbs. Although it is talking a bout a single carb it states the same basic procedure for multi carb set-ups. I guess just adjust them all identically.
It says, have the boat in the water warmed up on the trailer and at idle turn the L/S needle IN/OUT from factory setting till the motor revs to it's highest and if you go to far then it will start to fall off. at that point go back to where it's revving to it's highest and leave it there. obviously do this with 3 carbs and try to get them even.
Then, run it and come to the dock and go to the H/S needle and turn it 1/2 turn out or richer and run it. If it runs worse then go the other direction or vise-versa etc.... Once you've found the optimum power, turn out 1/4 turn and your good.
Does this sound like a good way to tune to you?
