Hi OPT,

Just as a follow up on my 2005 Polaris Scrambler Project Transmission Post from a few posts ago, I ended up buying a working used transmission due to a lot more gear and case damage hiding behind the bearing. So I have the rear axle put together, new transmission put in and it works! Now Im moving on to the rest of assembly and I have a question about this style of carburetor for the Polaris 500. Im used to the Polaris 400's slide throttle body where the needle goes up and down with the throttle, this carburetor looks like it controlled by an inner butterfly. When looking through the carburetor I see a needle and it goes up and down with my finger but doesn't looked controlled by the throttle because when I press the throttle it stays in place and doesn't move up. The scrambler accelerates like it should but I want to make sure Im not missing anything so that I don't lean the motor out in case in case it should be attached the throttle and the connection came undone during transit. (Which has happened to me before)

Thank you for the education sessions, do you have a PayPal where I can throw a donation your way - you have always been a great help.
Brad

 

This is a vacuum operated carb. When you give it throttle and the butterfly opens and engine vacuum provides the lift for the slide.The rubber diaphragm at the top raises up,the spring puses the slide down when throttle decreases. The more throttle,the more lift.Same thing for the fuel. Vacuum line on the right side of the carb goes to the fuel pump.The more throttle the more vacuum this line pulls on the fuel pump which delivers more fuel to the carb.A little more to these carbs than the old cable operated slides.Here's the fuel section of the manual that shows most of the carbs used on Polaris atvs.https://www.google.com/url?sa=t&rct=...,d.aWw&cad=rja

 

Awesome, I appreciate the resource!