What's wrong with my servo?

[RC Everything]

Please take a look at the video in the link below. Any one has this problem before? The servo is behaving very funny. This is a truck by 30°N, everything is stock. You can see that the transmitter is just beside the truck. I have changed everything and the problem still exists. Servo, transmitter, receiver, kill switch, ignition coil and battery have been changed.

The next thing to change will be the engine itself. I think the engine with the kill switch is causing the problem. If the kill switch is disconnected, the servo is fine. But I cannot run without a kill switch. I have replaced 3 brand new kill switches to this truck and the same happened. Put those kill switches on a Baja, it work fine. The one on the Baja originally, I put it to the truck and the same problem happened.

Any one has this problem before?

 

[niz55]

Same happened to my buddy 30N buggy with the same servo setup. It turned out it was his throttle/brake servo causing the glitching.

 

[RC Everything]

Same happened to my buddy 30N buggy with the same servo setup. It turned out it was his throttle/brake servo causing the glitching.

Interesting. I have only changed the steering servo. Maybe I changed both servos and see if it will resolve the problem before changing the engine... My truck is also by 30N.

 

[Clubin]

It won’t be the engine.

 

[RC Everything]

It won’t be the engine.

The issue happened only when any kill switch is connected while the engine is running. But those kill switch used on other engines in another cars are working well. I am using this kill switch as shown in the attachment below.

 

[Clubin]

Yes dynamite rebranded them. That’s all I use.

 

[RC Everything]

So anyone has any idea what is the problem ? I need to solve this problem so that I can race this brand new truck...

 

[Clubin]

Your throttle and brake servo
Post 2

 

[RC Everything]

Your throttle and brake servo
Post 2

Sometimes I really wish it is so easy that changing the throttle and brake servos can solve my problem.

I have removed the stock servos and change to PowerHD servos. But the problem still existed. You can see that I am using Sanwa MT-4 transmitter now. Not the stock Flysky GT3B.

It is always good to have some strange problems for us to ponder . Actually, when I was pulling the pull start, the servos already glitched. Every pull, the servos glitched.

By the way, I have changed the ignition coil of the engine and added some isolation between the ignition coil and engine. But make no difference. The servos still glitched.

Any comments are welcome before I change the stock engine to a Zenoah G320.

 

[Clubin]

So what can we eliminate?
Engine. I’ll eliminate that. We all use these engines

Servos. You’ve tried all new servos. Still does it.

The failsafe. Does it kill the engine and work like it’s supposed to?

Tried a different battery?

You tried a totally different radio and it did the same with the flysky?

Doesn’t Leave much not changed.
1. Engine kill switch. Try remove it. The engine will start and run if you unplug it.

2. Battery.

 

[Seandonato73]

Spark plug cap or non resistor plug pull cause it to glitch

 

[spents]

you say that the servo glitches when you pull the engine over mate,
try a ferrite filter over the servo wire, you know the filter thats on the killswitch wire,
sounds like interference, it sometimes works and sometimes doesn't, but worth a try cos they're cheap ,

https://www.rcmodelz.co.uk/electric...1325-0530-ferrite-filter-clip-on-5mm-2pc.html

 

[RC Everything]

Engine. I’ll eliminate that. We all use these engines

Not all engines are created equal. This engine is stock from 30°N. Made in China. Not a Zenoah.

Servos. You’ve tried all new servos. Still does it.

Changed. Maybe I will add the ferrite filter as suggested by Uncle Fester.

The failsafe. Does it kill the engine and work like it’s supposed to?

As mentioned in the first post, I have tried 3 brand new kill switches and the results are the same. I have more kill switches and I have put it in. It can kill the engine as designed.

Tried a different battery?

Yes. I have used the stock battery.

You tried a totally different radio and it did the same with the flysky?

Sanwa MT-4 is a good enough transmitter. I use this transmitter to race my Baja without issues.

1. Engine kill switch. Try remove it. The engine will start and run if you unplug it.

The only way to stop the servos to glitch is to disconnect the kill switch. But doing that will not be race legal.

Spark plug cap or non resistor plug pull cause it to glitch

What do you mean? I have changed to a brand new ignition coil including the spark plug cap. But it doesn't help. What is a 'non resistor plug pull'? How to a change to a 'resistor' one?

Can you give me more details? Thank you.

 

[Clubin]

Pick up another kill switch. Killer bee. Have you tried another kill switch?
^^ those are the kill switches I have in 2 mcd’s and 2 Baja’s and a vesla. Never had any issues.

Maybe you got a bad one.

 

[RC Everything]

Pick up another kill switch. Killer bee. Have you tried another kill switch?
^^ those are the kill switches I have in 2 mcd’s and 2 Baja’s and a vesla. Never had any issues.

Maybe you got a bad one.

I have tried 3 different brands of kill switches (see attached photos) Rovan, Dynamite and RCexl. How can all these kill switches are bad? I have used those 'bad' kill switches on my Baja with a Zenoah engine and it work well.

 

[niz55]

Changes out the coil system with a zenoah. If you can, just return the car back to rovan and buy 5T 2.0.

 

[RC Everything]

Changes out the coil system with a zenoah. If you can, just return the car back to rovan and buy 5T 2.0.

Agree. I will change to a Zenoah G320 and update all if that will resolve this problem. Also, I will install that engine to another car and see if it has the same problem on the car.

It is hard to return the 30°N truck as I bought it directly from China. Losi 5T 2.0 is about 3 times the price of a 30°N truck.

 

[RC Everything]

Good news RC experts, I have resolved the problem without changing the engine! Why I have never thought of that?

All I need to do is to replace the stock spark plug to a NGK. You can see the stock spark plug in the attachment below.

Really thank you for all the comments! This problem has been with me for months. I can finally race the truck now!

 

[Seandonato73]

Not all engines are created equal. This engine is stock from 30°N. Made in China. Not a Zenoah.



Changed. Maybe I will add the ferrite filter as suggested by Uncle Fester.



As mentioned in the first post, I have tried 3 brand new kill switches and the results are the same. I have more kill switches and I have put it in. It can kill the engine as designed.



Yes. I have used the stock battery.

Sanwa MT-4 is a good enough transmitter. I use this transmitter to race my Baja without issues.



The only way to stop the servos to glitch is to disconnect the kill switch. But doing that will not be race legal.

What do you mean? I have changed to a brand new ignition coil including the spark plug cap. But it doesn't help. What is a 'non resistor plug pull'? How to a change to a 'resistor' one?

Can you give me more details? Thank you.

There are spark plugs that have resistors built into them to suppress rf noise, the factory zen plug uses one. Cmr7h I think is the correct plug.

I have tried 3 different brands of kill switches (see attached photos) Rovan, Dynamite and RCexl. How can all these kill switches are bad? I have used those 'bad' kill switches on my Baja with a Zenoah engine and it work well.

They dynamite and rcexl are the same thing, and with all the issues I had with dynamite in years past I can't in good conscience recommend them. Hopefully your experience is better.

Good news RC experts, I have resolved the problem without changing the engine! Why I have never thought of that?

All I need to do is to replace the stock spark plug to a NGK. You can see the stock spark plug in the attachment below.

Really thank you for all the comments! This problem has been with me for months. I can finally race the truck now!

There continues to be issues with quality control (or lack of) with knock off products, spark plugs in particular will give issues.

 

[RC Everything]

Some updates on the issue. I have put the faulty spark plug in another engine that is mounted in a DBXL. To my surprise, it work perfectly!

The engine is a CY engine. What can you say about that?