Dynamite Killswitch & FlySky GT3B

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TrickyTris

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Hey all,

Looking for some help with my killswitch. Fitted it to a stock 29cc CY ‘Fuelie’ in my new 30DNT.

I fitted the Dynamite Killswitch following a suggested YT video and it appears to be working in so far as the red light comes on, channel 3 button turns the light off & turning the transmitter off applies the brakes then the light goes off.

However, in order to get spark so I can start it up I’ve had to unplug the ignition wire. With the ignition wire unplugged, the red light still comes on & turning off the transmitter still applies the brakes. But of course I can’t kill the engine using the channel 3 switch.

In order to fit the ignition killswitch, I had to swap one of the plugs with a ring crimp as my engine’s ignition coil only had a positive plug slot closest to the engine, with the negative being a ring crimp bolted down closest to the pull start.

The STOP button on the engine still functions fine.

Anyone have any recommendations on what to try to get it working 100%? Obviously I can’t swap the plugs without completely cutting & re-wiring them & can’t understand how they’d be wrong when it’s the way it was from factory?

Thanks in advance!
 

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Correct, I’ve just completed the engine break-in process with the killswitch ignition connection unplugged. Once plugged in, there is no spark. Red light in the battery tray is functioning as if there is nothing wrong. (Solid red).

I also tried with no voltage protection (both jumpers unplugged) to check it’s not due to the rx battery voltage.
 
Wondering if I swap the polarity of the Stop button if that might make a difference?

Could it be my negative ring crimp hasn’t got a good enough connection?

I can’t make sense of this as surely if one of the polarity of the wires was wrong or had a poor connection, the Stop button would also fail to work?

One step I did just notice in the manual as Im typing this that I skipped was re-binding the receiver with the Dynamite failsafe in the off position. What do they mean by ‘in the off position’? Unplugged or plugged in & holding the brake? I see no way to switch it off any other way..
 
Well I tried the step I missed & set up the failsafe as per the manual and it’s made no difference. Also installed the low voltage plug for 5v just in case and again, no change.

Guess I’ll take the engine out for the 5th time in a week and check all the connections again. Can’t see how they’re the issue though as the stop button surely wouldn't work if they were. I’ll try swapping the buttons leads to see if it makes a difference but not holding my breath.

Have also double checked the RX lead and it’s plugged in correctly.

At this point, I’m just starting to think I’ve got a faulty killswitch that’s just constantly sending a signal to kill the spark.
 
Tbh I stopped using dynamite one never worked and then I had another completely unbind my radio while I was running my car . Get a mod kill switch they cost a little more but they are worth it
 
I’ve managed to get ahold of some spade connectors, so I’m going to try switching the ignition coil wires around this morning. If that doesn’t change anything, I’ll buy the Mod killswitch!

One question though, it mentions needing An Aux slot and menu on controller. Will it work with an FS GT3B & RX? It’s only 3-channel and you have very limited menu control (can’t see a way to assign channels).

Thanks 👍
 
I switched the ignition coil wires over (was not fun trying to crimp the new ones on!) and have tested the spark and it’s now working as expected! Killswitch works, failsafe works & LED showing no issues! 😁

If anyone finds this post & is having the same issue as me; Ensure the red ignition coil wire is fitted to the spade or ring crimp closest to the pull start. Black negative should be on the spade closest to the engine. (Opposite of how it comes from the factory on my CY engine - for me at least!)

Shoutout to @sunoco for his post stating this can be the issue! (https://www.largescaleforums.com/threads/dynamite-kill-switch-issues.41799/post-508560)
 
I switched the ignition coil wires over (was not fun trying to crimp the new ones on!) and have tested the spark and it’s now working as expected! Killswitch works, failsafe works & LED showing no issues! 😁

If anyone finds this post & is having the same issue as me; Ensure the red ignition coil wire is fitted to the spade or ring crimp closest to the pull start. Black negative should be on the spade closest to the engine. (Opposite of how it comes from the factory on my CY engine - for me at least!)

Shoutout to @sunoco for his post stating this can be the issue! (https://www.largescaleforums.com/threads/dynamite-kill-switch-issues.41799/post-508560)
Huh….. I was using a dynamite kill switch too, and it was doing the same thing. Initially the damn thing was working though. I ended up throwing it in the trash and grabbed a heliantronics switch.
I’m glad you figured it out.
 
I’ve managed to get ahold of some spade connectors, so I’m going to try switching the ignition coil wires around this morning. If that doesn’t change anything, I’ll buy the Mod killswitch!

One question though, it mentions needing An Aux slot and menu on controller. Will it work with an FS GT3B & RX? It’s only 3-channel and you have very limited menu control (can’t see a way to assign channels).

Thanks 👍
That’s the remote I was using before I got my futaba .
 
Huh….. I was using a dynamite kill switch too, and it was doing the same thing. Initially the damn thing was working though. I ended up throwing it in the trash and grabbed a heliantronics switch.
I’m glad you figured it out.
Thanks bud! I may still look into the MOD killswitch, as I don’t like how many points of fail this dynamite one has. The mod one looks to have the switch leads soldered at least & a bit more cable to work with to make it neater!

I did my first break-in run where I got to actually drive it today. After 10-15mins of driving at 1/4 & 1/2 throttle bursts it cut out under throttle & then wouldn’t start again. I think the head gasket has gone as I could feel hot air blowing from the front of the engine head when it was breaking in on the stand yesterday on the last tank. Stupidly didn’t think anything of it as it was running fine. Compression feels soft & rubbish now. Fingers crossed it’s just loose head bolts or just a new gasket needed.. So far, I’m not impressed that a brand new truck can do this in around 1 1/2 tanks of fuel. 🙄
 
I would be checking the plug is tight as well as the head bolts : could be the mixture being too rich after initial break in , causing issues , but at the end of the day, the engine should be fine , if not contact supplier and get it changed out
 
Sometimes with flysky radio have to check endpoints or brake/throttle can shut off engine.Seems to be a raminator issue with factory raminator kill switch.As far as mod kill switch pushing 5 years in my 5t 2.0 with zero issues.Have to shut off any a.v.c. or traction control with it.
 
I would be checking the plug is tight as well as the head bolts : could be the mixture being too rich after initial break in , causing issues , but at the end of the day, the engine should be fine , if not contact supplier and get it changed out
Thanks for the advice!

The plug is definitely tight & sparking. Have (kind of) checked the head bolts with the tip of a hex key, but they were too tight to move in either direction. Got extended hex drivers coming tomorrow so I can check properly! Doing a visual inspection though, there are no signs of any leaking around the gaskets or any part of the engine whatsoever.

One thing I did do was change the pull start with an alloy one, which appears to be shaving the ends of the flywheel and also damaging the pull start itself. I’m wondering if it’s not gripping it enough & slipping now, so not giving the piston a good enough stroke to start? It grips enough to spark the plug but I can’t even get it to ‘pop’ when gently pulling it with the choke on. May swap the pull start back to the stock plastic & alloy one. Pics attached.

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Sometimes with flysky radio have to check endpoints or brake/throttle can shut off engine.Seems to be a raminator issue with factory raminator kill switch.As far as mod kill switch pushing 5 years in my 5t 2.0 with zero issues.Have to shut off any a.v.c. or traction control with it.
Checked the end points and ensured it’s all setup so it’s not going beyond what it needs to. Tbf to RCMZ, they even set the end points up when I’d taken it out the box, which is the first time I’ve ever seen that on a RTR model!
 
could be the mixture being too rich after initial break in , causing issues , but at the end of the day, the engine should be fine , if not contact supplier and get it changed out
Just to add, perhaps this could be the issue too. When it was running, it was dumping a lot of fuel/oil on the tarmac - so much that you could see lines on the tarmac where I’d driven it.

Is it normal to see a lot of black gunk around the exhaust tip & around the spark plug when taking it out too?

I’ll try leaning both needles out a 1/4 or 1/2 turn next time I try to start it. It’s been on the recommended factory settings the entire time so far.
 
Just to add, perhaps this could be the issue too. When it was running, it was dumping a lot of fuel/oil on the tarmac - so much that you could see lines on the tarmac where I’d driven it.

Is it normal to see a lot of black gunk around the exhaust tip & around the spark plug when taking it out too?

I’ll try leaning both needles out a 1/4 or 1/2 turn next time I try to start it. It’s been on the recommended factory settings the entire time so far.
Shouldn’t be dumping out that much, lean it out just a little at a time, 1/2 turns are way too much, try 1/8 turn increments.
I’m no expert but that’s the rule of thumb.
 
Sounds like it is stinking rich.
I would check you are getting FULL throttle when it is wide open as well.
Wear on the end of the flywheel is not good news, may need some spacer washers to get it away from flywheel when not engaged .
I would contact Rcmodelz if problems continue , my experience has been very very good with them.
 
Shouldn’t be dumping out that much, lean it out just a little at a time, 1/2 turns are way too much, try 1/8 turn increments.
I’m no expert but that’s the rule of thumb.
Thanks bud, will do!

The ground was wet so it definitely made it more obvious to see 😅

Sounds like it is stinking rich.
I would check you are getting FULL throttle when it is wide open as well.
Wear on the end of the flywheel is not good news, may need some spacer washers to get it away from flywheel when not engaged .
I would contact Rcmodelz if problems continue , my experience has been very very good with them.
It’s definitely very rich, though I figured I had to run it on these settings until the entire break-in procedure was done. Always been the way with my nitro models, but it seems these are quite different! I’m just hoping it being that rich hasn’t killed the engine. The amount of black oil it’s dumped out the exhaust and has been sitting in the engine is worrying me now.. The thing STINKS of burnt oil. Wonder if there’s a way I can flush it out before I try to start it again?

I’ve found RCModelz to be brilliant so far, but I have a feeling they won’t replace the engine if it’s dead, as I’ve fitted a killswitch & changed the pull start? Mind you, I’d happily send this one back as proof I followed their break-in guide!

or just go the whole hog and fit this
Think I’ll order the easy start kit with the flywheel and tools tonight. Will save me having to pull the engine out again in a couple days! My only concern is doing all this only to find out the engine is kaput..
 
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