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Old 02-17-2007, 01:20 PM   #1
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Default please help - stuck carb

anyone experience this? the carb seems to be stuck when throttle is applied and then i have to manually shut the carb to idle agian
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Old 02-17-2007, 01:46 PM   #2
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GReddy,
Not much info to go on but check the following:
1. Throttle linkage binding
2. Idle speed screw dragging on throttle slide (carb adjustment).
3. Stripped servo gears.
4. Transmitter trims.
Larry
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Old 02-17-2007, 02:21 PM   #3
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i know that it was even like that when it was new, so cant be the servo or trims

ive noticed that if you screw the idle screw in a lot more then needed then it wont be stuck and will slide smoothly
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Old 02-17-2007, 02:44 PM   #4
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GReddy,
Turn your idle screw counter-clockwise until the slide is completly closed then turn it clockwise until the slide opening is .3-.5mm. this a very small opening about a 16th of an inch. Let me know if this frees up the throttle binding because if it does we have some engine tuning to take care of.
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Old 02-17-2007, 03:30 PM   #5
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is it a rotary carb? if it is, it can possibly be that the idle screw is no longer in the groove on the slide and would cause it to hang up also. not as common on a slide carb but can happen there too. past that do you have return spring on throttle, also it could be that linkage was installed binded up from the beginning if it is a rtr.
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Old 02-17-2007, 05:02 PM   #6
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its a slide, i use those clear hair bands as return springs

the linkage you know how when you throttle it theres a collar to hold the sleave allowing the linkage to be pulled

but when breaking/returning to neutral theres a spring on that side so i guess that could cause the servo to push the spring instead of the carb valve, but even then the carb shouldnt be getting stuck right?
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Old 02-17-2007, 05:39 PM   #7
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Remove the linkage from the carb slide, move the slide in and out, it should be very easy almost silky smooth. The rubber bands should not be used as a return spring, they are only there to act as a fail safe. The spring on your throttle linkage is what returns the slide to the closed or any intermediate position. The collar that holds the spring against the servo horn should be adjusted so there is a slight pressure to alleviate any slop in the link. The idea is to allow the servo to reverse during the use of brakes without limiting the brake travel.
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Old 02-17-2007, 05:59 PM   #8
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yeah but its not smooth at all
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Old 02-17-2007, 06:12 PM   #9
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Is the idle stop screw backed out? If it is and the slide is still binding remove the idle stop screw completely, loosen the dust boot from the carb and pull out the slide. Check for signs of the idle stop screw gouging the slide in the alignment track and any other areas that may cause binding. The slide must move freely and smoothly.
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Old 02-19-2007, 04:27 PM   #10
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i tried it agian today and it seems to run great but when it reaches near max temp. the valve starts acting up and gets stuck

shutting the engine and testing the carb as it cools as long as i let go of throttle right away it doesnt stick but if i let go slowly it sticks and u can hear it "pop" back to close
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Old 02-19-2007, 05:03 PM   #11
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very weird. i would definetely disassemble the carb still and look at everything. also i wonder if maybe your servo is crapping out, or a stripped gear in it.
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Old 02-19-2007, 05:14 PM   #12
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its not the servo because i disconnected the linkage and moved it by hand
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Old 02-19-2007, 09:30 PM   #13
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do you have any engines around that the same size? ie .12-.18 /.21 .30? If so take another carb and throw it on the engine. engiens dont mind having diffrent carbs . infact some engines run better with diffrent carbs
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Old 02-19-2007, 09:47 PM   #14
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i have another its the carb from the rtr engine from kyosho but that carb is eh..
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Old 02-20-2007, 09:42 PM   #15
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maybe it just needs to be cleaned..... I noticed build up on mine today !!!! that hinders performance !!!
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