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Old 11-18-2014, 01:44 AM   #1
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Default hpi rs4 evo 3 clutch engaging at low idle.

hey everyone, my clutch is engaging at very low idle causing the car to run away, if i put in on the ground, it stalls, does this have anything got to do with the low speed need? anyone know how to fix this problem?
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Old 11-18-2014, 05:03 AM   #2
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Either the clutch springs are too soft, the clutch bell bearings have seized, or the idle is set too high. Reset the needles on the carb to the factory settings, and see if the engine holds a decent idle (the wheels shouldn't turn at idle with the car on the ground). If the car wants to roll after resetting the idle to a lower idle speed, you should check the clutch to make sure the springs are installed properly and in good condition. While the engine is out of the car make sure that the clutch bell spins freely on the crankshaft - if it doesn't, replace the clutch bell bearings, reinstall the engine and try again.
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Old 11-19-2014, 01:50 AM   #3
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thanks for replying, i changed out the spring even though it was fine, it still wants to engage, even at low idle, is it some thing to do with my LSN??
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Old 11-19-2014, 04:59 AM   #4
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Probably not related to the LSN, as that adjustment is responsible for the fuel/air mixture strength at idle speeds. Does the clutch bell spin freely when the engine isn't running?
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Old 11-19-2014, 01:50 PM   #5
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yes it does, with the wheels off the ground, and it spins freely, turning the wheels with it because its on the spur gear, i even changed the clutch spring which look good to me anyway, but now i have a brand new tight spring on my clutch shoes, could it be that my clutch shoes wern't put on properly?
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Old 11-20-2014, 05:24 AM   #6
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Incorrect spring/shoe installation could be the problem, or the idle could be set too high. Without starting the engine, turn on the radio and the receiver battery in the car, and remove the air cleaner. You should be able to see the slide (or barrel, for a rotary carb) inside the air inlet, and a small space along one side of the inlet. The space between the side of the carb and the edge of the slide should be 1mm or less; measurement for a rotary carb would be similar. Any larger than that, and the engine would most likely be idling at too high of a speed to keep the car stationary without using the brakes.
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Old 11-21-2014, 04:38 AM   #7
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i dont think that could be the issue, the clutch is engaged at very low idle, like the engine would be about to die and the wheels still spin
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Old 11-21-2014, 06:03 AM   #8
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That leaves few alternatives if the clutch bell bearings are good, and the idle is set properly - the clutch springs either need replacement, aren't installed properly, or POSSIBLY the clutch shoes are installed backwards.
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Old 11-21-2014, 02:50 PM   #9
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i might have installed them backwards, iff i try to see if i did how can i tell if they are backwards? and also will my spring still be useable after i take it off?
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Old 11-22-2014, 02:24 AM   #10
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Backwards should not be a problem, and if you do not bend the springs you can re-use them.
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Old 11-22-2014, 03:03 AM   #11
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well i just fliped the shoes and it worked! thanks for the info guys
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Old 11-23-2014, 09:31 PM   #12
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By hand Does your clutch bell spin without any wheels turning? If you are running at hi idle on ground. You could have melted the shoes. I'd disassemble your clutch and inspect the assembly.
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Old 11-24-2014, 05:56 AM   #13
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Quote:
Originally Posted by Roelof View Post
Backwards should not be a problem, and if you do not bend the springs you can re-use them.
Factory HPI clutch springs are notoriously weak for the 1/10 scale nitro clutch setups. It's probably the only setup where installing the clutch shoes backwards might make a difference.

OP - glad the problem was sorted out after reversing the shoes...
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