Need help breaking in!!

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RS4 Owner14

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Ok today i just got my first nitro rc car and im having troubles breaking it in. Right when i start it up the car just takes off like im pulling full throttle on it. i don't know what to do since this is my first rc nitro car. is this normal? is it the idle? and how to fix. Thank you. and the car is an HPI Nitro RS4 Evo :(
 
RS4 Owner14 said:
Ok today i just got my first nitro rc car and im having troubles breaking it in. Right when i start it up the car just takes off like im pulling full throttle on it. i don't know what to do since this is my first rc nitro car. is this normal? is it the idle? and how to fix. Thank you. and the car is an HPI Nitro RS4 Evo :(
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first check that the servo's are set correctly, make sure the throttle servo is trimmed with the throttle just opened, you can do this thru the radio
 
Okay I did this and it was still spinning the wheels fast and i was told by a friend to adjust the Idle and low and high end needle now it won't even start. the roto-start keeps getting stuck and the fuel isnt igniting. And fuel is coming out of the exhaust after a little bit of trying to get it started. I checked it for flooding and did everything to fix it. I NEED HELP PLEASE
 
set the needles to the factory recommended setting. should be in the manual. take the air filter off and set the idle screw so that you have no more then 1mm opening on the throttle with the brakes applied on the radio. and start it up if it is spinning like crazy still adjust the idle screw only.
 
ok pull the glow plug out and very carefully put it in your ignitor. see if all the coils turn orange. if they do its good. next with the glow plug out turn your car upside down and turn it over with the roto a bunch of times to clear the axcess fuel out of it. put the glow plug back in warm the engine up with a hairdrier and try to start it
 
Ive done all of this. is it the carborator that needs to be tuned? its at factory settings shouldnt it be able to start? I haven't even been able to break in the car yet.
 
ok it still wont start? turn just the high speed needle in about 1/2 a turn and retry it. but turn it over and with the glow plug out and roll the engine over again to clear any access fuel out of it
 
If this is a second hand rig, or is used - been in the shed a while - check for leaks.
These can be the locking bolt for the carb working loose, tubing torn or stretched, and the exhaust grommet/seal - which gets fatigued and can be broken if the exhaust is moved around.
If you've reset to 'factory', the radio gear's working OK, my guess is you've an air leak.
The other 'obvious' check is the cooling head bolts - are they tight or not?

You mention you're using a rotostart - make sure there's no air leak through that.
(I've 'got the t-shirt' on all of the above with my LST2 - still running super strong now with an LRP ZR30 Spec2 inside!!).

Al.
 
Well today ive been looking at it and it looks like the fuel isn't leaving the carb to the engine. And its not second hand owned its brand new. Got it for christmas.
 
Pressure needs to build up to pump the nitro fuel around.
This normally happens 2 ways:

1. There's a primer bulb on top of the tank - like on the LST.
2. With the glow igniter on the plug, the rotostart in position, PUT YOUR THUMB OVER THE EXHAUST for a few rotostart cycles - you should see the fuel pump into the engine. Once it's there, take your thumb off, or you'll flood it.

It should start now!! Heat cycle the engine - run a tank through then let cool down; run another tank through, then let cool down.
Follow manufacturer's instructions. HPI talk about idling the first 1 or 2 tanks, where Traxxas talk about RUNNING GENTLY ON VERY LOW THROTTLE - you can't but with nitro - it's not Petrol - YOU MUST, to bed in the piston and cylinder without trashing them.

Al.
 
Any progress?

I've been having hours - well groups of 20-25' - of fun with my large tanked LST2 spec Losi Raminator the last few days - still strong.

Original part .... the antenna stem and bulb on the end - that's all.
I'm now running an LRP ZR30 Spec2 engine on it's perhaps 20th tank (or more).

Al.
 
Yea got it up and going for about 4 tanks got it broke in. Gotta tune it but...... the roto start that came with it had a defect. It fried and started smokin and now won't even turn on. Gonna call up HPI tomorrow. On there website it says it'll take it about 2 weeks for them to get it and replace it. :( So I got to run my brand new nitro car for 4 tanks and now I can't run it for 2 weeks :/
 
Does your engine have Rotostart only, or is it a pullstart as well?
If it's only a Rotostart, if you have a good electric drill, you can use this.

Be VERY CAREFUL. The engine can flood, and you can get hydraulic compresson, which can blow the cylinder if you force it with a drill - just be sensitive, but I don't see why you have to wait!!

Al.
 
I already did use a drill but the roto-starts bit that i put in the drill, the front part of it which has the metal pieces sticking out the sides broke off after using the drill because my drill was too powerful. So the roto-starts bit just spins inside the engine. The car is 100% fine. Just the whole roto start itself.
 
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