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idle problems

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theg12eato17e

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Hi, I'm having trouble keeping the engine at idle. When I start the engine, it runs for a few seconds and as soon as I turn on the transmitter on the truck, it dies. Any answers to my problem? Also I turned the settings back to factory.
 
Bad juju. Never turn on the transmitter after you have started!!! Always turn it on before you start and before you turn on the receiver.

To fix your specific problem, adjust the idle screw in a little and that should work. It's not a contest to see how low your rc idles. As long as it stays running without the clutch engaged then it's good.
 
I would tighten up your Idle screw a little bit. And first rule of thumb, DO NOT start your ride without your transmitter and receive both being ON! Thats when you are most likely to have a run-away.

So, with the TX and RX on, pull the airfilter off, look down the carb, with the brake fully applied, set your idle screw so that there is a 1 to 2mm openning. After that, let off the brake and set your trim so that the opening is the exact same as what you just set.

Whats probably happening is when you start it without the TX on your idle opening is good, however, when the TX is on it is fully closing your carb. It should not be possible to fully close the carb. Thus, the need to tighten the idle screw.

Hope I didnt confuse you.
 
What kind of truck is this? What is the engine? Why is your radio off when you start your vehicle? I did this when I was new I admit the very first car I got the very first day and it ran away at wide open throttle and crashed into curb and broke big time so its a good habbit not to do that anymore. Welcome
 
It's the Savage, I've just been having problems since I purchased it 2 weeks ago. I don't know what to do with it. I can't run it without it dying on me. I've been able to run it for about 5 minutes then it would stop. I bought a Radio Shack IR Thermometer so I can read the engine temp. Can anyone tell me how to tune this thing right? I set the needles back to factory so I have a baseline of where to start. I've searched across the board for possible solutions, but still I'm having a difficult time running the truck. I can't push it in full throttle and if I do, it sputters and sounds like it's about to stall. Thanks in advance.........
 
Initial thought is it is rich and the idle is to low. Sounds like maybe the engine is loading up with fuel and flaming out. Hard to tell though
 
Turn the low speed and high speed needle in 1/4 turn from factory. Make sure your idle is adjusted so it runs with the brake applied and starts easily.

This should get you better than where you are now.

Dont forget, your sweet spot on almost any engine can be 1/8th of a turn away ;)
 
Originally posted by Çh®i§tiªñ
Turn the low speed and high speed needle in 1/4 turn from factory. Make sure your idle is adjusted so it runs with the brake applied and starts easily.

This should get you better than where you are now.

Dont forget, your sweet spot on almost any engine can be 1/8th of a turn away ;)


Now when you say this, do you mean to richen or lean it out. I will try tomorrow since it's almost 10 pm, but If anyone has any other suggestions. I'd be greatful. I know that before I got the RS Thermometer, the heat sink would almost burn to the touch, so maybe it's a factor of overheating as well. What else can I do so that this won't happen?
 
It sounds like the engine needs a real good tune job. Be careful when setting the needles back to factory settings, the needles are steel, but the other stuff inside is rather delicate brass. Neer touch the mid range needle (the one on the opposite side of the carb from the throttle linkage). Follow the previous posts about 1) NEVER start the engine with the Tx and/or Rx off. That's in the savage manual, read it. 2) set the idle adjustment screw so that it's open about 1 to 2 mm with full brakes on.

If there are other nitro guys there local, get them to help. There is no substitute for actually hearing and seeing a tune job done, and actually doing it yourself with guidance. We can explain all day, but actually seeing it done is magic. You were smart in getting a temp gun, but having a good starting point is really helpful when trying to get an engine running.

With that said, here's my 2 cents on getting you running.

If the engine will start and idle for a bit but dies with any application of throttle, you HSN is way too rich, and maybe the LSN also. Lean the HSN 1/4 turn at a time. You should eventually get it to accelerate without dieing. When you get to this point, start using the temp gun often. Now you want to focus on the LSN. Let it idle for about 5 to 10 seconds, then pinch the fuel line. If it keeps on idling for a while, then speeds up and dies, the lsn it too rich. If it dies right off the bat, it's too lean. Adjust the LSN so that it idles for about 4 to 5 seconds before it speeds up and dies. This is you base for further tuning.

What you're after is a 5 to 10 second idle, then WOT without much bog down. The bog down is caused by fuel loading up in the case. Once you get this set, tune the HSN so you're within the operating range of the engine. 220 to 270 for most 21 size engines. 220 is pretty rich, above 270 is risking damage. If you're just bashing, tune it to about 235 at a full tank and check it often as you run, since the savage tank leans out as you burn fuel. Once you get it tuned, you shouldn't have to touch the LSN again, just the HSN. Once again, NEVER TOUCH THE MRN.

I hope this helped.
Whitt.....
 
300 degrees (normal run temp when tuned for performance) is pretty dang hot to the touch! Take temps around the outside edges of the glow plug on the head itself.

Lean is what I mean. From stock 1/4 turn in on each. Clockwise.
 
Thanks for your help guys, I'm glad I got some answers. I will see how it goes tomorrow morning. I've had it tuned by my local hobby shops, but still when I take the truck back home, it still runs like crap. I'll just mess with it to see what I get.....
 
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