Need help with brake / engine issue

[PappaD]

I have searched for an answer with no results. Simply, when I apply the brakes the carb closes too much and engine dies. I'm sure there is a simple adjustment so please tell me. It's in a Dark Thunder dragster with a picco p3 .28 engine.

Thanks in advance!

 

[dan14]

I'm not to fimular with this engine but this had happend to mine adjust your idle stop, adjust by a 1/4 of a turn each time .

 

[olds97_lss]

With the engine off and the throttle servo at idle or "neutral", you should be able to look down your carb neck (with the filter off) and see about a 1mm gap on one side. If you move your throttle servo to apply the brakes, the carb should not move. There is an idle adjustment screw that dan14 is talking about. It's purpose is to stop the carb from moving when you apply the brakes and it's where the carb should rest when your throttle servo is at neutral.

If the carb barrel moves when you apply the brake, your trim is off and your idle is off. When the servo is at neutral, it should be putting a slight pressure on the carb holding it against the idle screw.

See the little black screw on the side of this:

That's your idle screw. I believe that's a pic of your carb: http://www.amainhobbies.com/product_info.php/cPath/68_235/products_id/7464

 

[PappaD]

Thanx guys I'll try it out. Do I tighten or loosen to stop it from moving when I apply the brakes. I was thinking I would just adjust the brake so it engages when I let off the throttle as it's on a dragster and needs to stop anyway. Any thoughts? Would it mess up the servo?

 

[Candyman]

The easiest way to make sure you get it right is to remove the air filter. Then push the throttle closed with your finger. If it is closed all the way, turn the idle screw a couple turns to see if it opens. I believe clockwise is the proper direction on that carb. You want to make sure there's about a 1mm gap in the carb even when the brakes are applied.
As far as setting your brakes so they are engaged at neutral, it's called "drag brake". Some people do that. It won't really have a huge effect on your servo and since it's on a dragster it probably won't be a problem.

 

[bourney2006]

you need to push your idle stop screw in about 1/4 of a turn