Help needed

[ellmo1]

Hi

i have a problem with my losi 8ight 2.0. When i appley full throttle down on the trigger and then relese it, It keeps going at full throttle? I have recentley installed a new button head and this button head is a 21 dynamite xp, Someone said they are alike? It also has been stutering. I have also put it back to factory settings. It also has a new turbo glow plug. Could the engine need a clean? Any help would be appreciated.

Thanks

Edited August 9, 2011 by ellmo1

[ellmo1]

??????

[badger906]

recreate it on a brick, is it the servo thats slow returning, or is it at neutral?

[ellmo1]

When i release the throttle trigger the servo goes back to nutrual and the engine keeps going at the same speed.

Thanks

[badger906]

either a massive airleak, or youve a false idle.. squeeze the carb shut and see if it still does it

[ellmo1]

If i squeese the carb shut wont the engine switch off?

Thanks

[Monkey_Man]

If i squeese the carb shut wont the engine switch off?

Thanks

no because the idle screw should stop it closing fully if set correctly

[ellmo1]

so just squeese the carb shut? I think it is normaley like that when no throttle apllied? Dont know what your talking about. LOL:)

Thanks

[ellmo1]

???

[Ruhel]

One way to check would be to remove your air filter and with engine OFF apply full throttle. Then let the throttle return to neutral. When it returns to neutral see if the carb closes or stays open.

[Nitroholic]

what the guys are asking is whether your carb is actually returning to idle.

There are various ways of doing this, and it is the start point of curing your problem.

Here's the way I would do it:

With the engine off, remove the air filter. Power up your transmitter and receiver as normal. This allows your servos to sit at their natural idle position. Make sure you have no trim on the throttle.

~Your idle gap should be visible at around 1mm.

Press the brakes and confirm the idle gap does not close. The idle screw should prevent the slide closing further. this will confirm your idle screw is correct and that you have a genuine corect idle setting.

Now hit the gas, and you should see the throttle slide open fully. It's easy to do this with the engine off.....

Now release the throttle and see if the slide returns to it's correct idle position. If it sticks open or partly open, this is the problem. Might be worn or damaged slide...or it could be the servo or linkage doing it. all are easy to spot and check.

You can check the servo/linkage bs isconnecting it from the carb and repeating the above. If you manually pull the throttle open and release, it should be possible to gently push the slide back...it won;t go on it's own....but it should lside smoothly shut. If it sticks...new carb time.

If that is OK...check the servo returns smoothly. If it doesn't...you may have to replace it.

If you have a servo problem....it may not be the servo! What you can also do is to check the recevier is working correctly. Unplug the throttle and steering servos. Plug the throttle servo into the steering channel, and check it operates smoothly. Then put th esteering one into the servo channel...does that operate smoothly both ways. Do this with the engine off naturally!

If you have a servo problem it will fail in both channels....if the problem stays with the throttle channel....the RX is shot.

Once you know th elinkage moves properly, the servos work and the carb slide works as it should, you are then left with an engine problem....

Could be a massive air leak....and considering the work you have just done...I am wondering if the head button is actually sealing. Look for signs of fuel leaking around the join. You may also have excessive fuel build up causing problems....so reset to factory defaults and try and tune it again if all else seems OK.

Main thing is to check ALL the possibles. That's why the guys are suggesting you check your throttle. It may seem obvious....but unless you actually see what the throttle slide is doing, you are just assuming all is well. You can eliminate these things .... but you actually want to see that what happens INSIDE is what it looks like on the outside

[ellmo1]

Thanks Nitroholic!

Everything servo wise is working fine, But when i took the button head off after a run yesterday, I saw they was some sort of liquid (fuel) on the button head. I think my engine is leaking:( So guys what will i need to seal it off.

Thanks

[Nitroholic]

If it's properly torqued down, you shouldn't need to seal it. I have never had to seal a head button.

Make sure the bolts hadn't worked loose and that it was properly seated.

Was the motor hard to start?