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Old 06-08-2009, 09:33 AM   #1
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Default Have you Ever Reached That Point

ok so heres the deal ive reached a point in my tuning process that i dont know what else to do everything is running perfect temp. goes up in down but still within range... as long its not in the middle of the hot iraqi day... but the problem that i am running into is that when i hit the brake the engine cuts off and when i say cuts off i mean it seems like it completly cuts off the fuel or somthing i need help any ideas
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Old 06-08-2009, 09:35 AM   #2
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check your throttle linkage. when you hit the brakes it might be closing the carb. if so all you have to do is reset your linkage. so that at N the carb is fully closed and when you hitthe brakes it does not move. and then just turn your idle screw in to open it back up.
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Old 06-08-2009, 09:39 AM   #3
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Does it idle ok if you don't brake? I was going to suggest looking at your clutch. If the springs are dead or the shoes are hanging up you could be stopping the engine by locking the brakes up before the engine has idled down and the shoes are still dragging on the bell.
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Old 06-08-2009, 09:49 AM   #4
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The idle is fine it will idle all day as long as i dont hit the break im going to try to reset the linkage and see if that helps and that might be the problem because i just put a grp engine on there with new futba servos....
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Old 06-08-2009, 09:53 AM   #5
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Originally Posted by Davidka View Post
Does it idle ok if you don't brake? I was going to suggest looking at your clutch. If the springs are dead or the shoes are hanging up you could be stopping the engine by locking the brakes up before the engine has idled down and the shoes are still dragging on the bell.
I would recommend this too. This happened to me once. Soon as I hit the brake the engine cuts off. A friend said it was my clutch shoes. I took off the clutch bell and the one of the shoes was cracked in half. I also learned that from this forum also.
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Old 06-08-2009, 09:55 AM   #6
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All you have to do is pull the air filter assembly off..(clean the outside of the assembly and the engine....You don`t want any dirt getting in the carb)With the air filter off look down into the carb and hit the brake.If it closes completely then it is your idle gap......If it doesn`t close and there is a 1-2mm gap them its most likely a clutch...

hope this helps
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Old 06-08-2009, 10:15 AM   #7
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the problem isn't the linkage, the problem is that the idle gap isnt open far enough by the screw setting. hold the brakes on and set the screw so it idles. at this time you are using the neutral position on the radio to hold and idle gap open....
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Old 06-08-2009, 10:20 AM   #8
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the problem isn't the linkage, the problem is that the idle gap isnt open far enough by the screw setting. hold the brakes on and set the screw so it idles. at this time you are using the neutral position on the radio to hold and idle gap open....
+1... what's happening is when you have your radio turned on, the servo holds the carb open just enough. this is due to your trim setting. the zero point pulls the carb open just enough. when you hit the brakes, the servo is closing the carb too far and causing your engine to die. to stop this, you must turn the idle screw in to create a bigger idle gap. this way, the carb stays open as much as it needs to properly idle regardless of servo position.
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