What have I done!!!

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Garry Clarke

RC Newbie
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Hi Guys

Please bear with me on this as a fair bit has happened to my car and will try to be as clear as noob can

1-problems started when I fuelled up set all factory settings on the carb,made sure trim on handset was right and the throttle idle was 0.5-1mm.
Fired it up and was running fast so adjusted the idle to a nice idle then out of the blue it screams it head off to full rpm,
I double checked everything again even carb settings,got the excess fuel from the engine and started it again,it idled for a few seconds and then went to full rpm screaming it's head off,I killed and again checked and checked the car.
Then I discovered the blue plastic spur gear (fitted to my eb4-s2.5)..was stripped and chunks out of the thread!!
How the hell did that happen??..any ideas would be welcome,
I only tried to start it and had only previously used my rc for a grand total of 10mins
I've ordered a new one and have stripped the car ready,not as hard as I thought but I no setting it properly takes a bit of time but I will do it..

MY MAIN CONCERN

Turning the engine over (with glow plug fitted) doesn't feel right now,it's hard to explain but it feels a bit stiffer on the pull cord and when it's gone from TDC there is usually a smooth transition to BDC but it feels stiff,
Also noticed that when I slowly pull on the cord the main flywheel does not turn as I've marked BDC to help aid cooling when/if I ever get to use the car...by my finger I can turn the engine over clockwise but it doesn't like it anticlockwise...

Also the thing that goes onto the flywheel that obviously drives the spur gear just spins freely like it's not attached to anything,is that supposed to be free like that??

I've got a bad feeling I've done some internal damage but I just can't work out how the hell the spur gear got munched and after a few seconds it revs it's nuts off!! ,

Any advice on this would be great guys


Garry
 
When I strip a spur on my revo and hit throttle it gets really high pitched sounding. The pat attached to your spur and flywheel is a clutch bell with clutch shoes onside it. It spinning freely is a good thing my guess is the mesh was improperly set either to tight or loose mesh was a pita for me to get right but once I did it's easy. If that doesn't work I'd take the clutch bell and fly wheel off and possibly the ba c k plate look for broken stuff you might of broke something with prolonged high ramand with no resistance
 
not sure why it was revving up like that. did the throttle servo move when it revved up? as for the spur gear, it probably got damaged when the engine reved up. Thats why they are made out of plastic so if something goes wrong you break a 4-5 dollar spur instead of something much more expensive and difficult to change.

As for the engine not turning over smoothly, Id check the one way bearing and the clutchbell bearings and make sure they are working properly. The owb bearing should freely spin in one direction and not at all in the other direction. the clutchbell bearings should spin freely both directions. Also check the pull start for damage.

The clucthbell (the part that has the teeth on it that goes over top the clutch shoes) should spin freely. As the flywheel spins faster when the engine begins increasing in RPMs the centrifugal force should overcome the force of the springs that are holding the clucth shoes down. As this happens the clutch shoes will open up and eventually grab ahold of the inside of the clutchbell and force it to spin which inturn spins your spur gear and ultimately makes the kit move. heres a couple pictures of a fly wheel. one with teh shoes on it and one with the shoes off of it so maybe you can get a better picture of whats happening.
images.jpg

images2.jpg


this clutch only uses two shoes but this shoes exactly how the shoes behave when at idle speed and at higher RPMs.

index.jpg
 

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Can you add some additional info? Is your EB4 new or used? Do you have the AM radio or the 2.4ghz radio?
Did you turn on the radio, then the receiver, and test the function of the electronics before starting the engine?
Do you have a throttle return spring?

Some of the European model EB4s use a center spool with a plastic spur gear instead of a center differential.
The plastic spur gear is designed to disintegrate if your running gear binds up for any reason.
Its a piss poor design IMO, if It were my car, I'd replace the spool with a center, oil filled differential. With a few additional parts its a direct swap..

Definitely open up the engine and inspect for damage, also inspect your clutch assembly.
You should also check over your running gear for any kind of binding. Over revving the engine while the car is immoveable could also cause the spur to shred..
Here's some part numbers you'll need if you decide to go with a center diff.

http://www.ebay.com/itm/NEW-Thunder...Control_Parts_Accessories&hash=item43a393952f
http://www.ebay.com/itm/Thunder-Tig...Control_Parts_Accessories&hash=item339437f782
http://www.ebay.com/itm/NEW-Thunder...Control_Parts_Accessories&hash=item5ae859d5e0
 
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Many many thanks for the replies and advice guys.

I will answer the questions asked when I've finished work so don't think I'm ungrateful

All the best

Garry
 
Guys
My apologies for the delayed reply as been trying to sort the rc out and thanks to a kind hearted member of another forum and living only a few miles from me kindly sorted all the problems out and tuned it to perfection so as you can imagine I'm a very very happy man :)

Can I say a big big thank you for your replys with the lack of information I supplied but I'm a complete NOOB so thank you again for your input


Garry
 
The little grub screw that holds the rear propshaft (spur assembly if thats correct) had fallen out causing it to rev up and it wasn't till we took it apart it was realised,
New spur gear fitted and adjusted,also needed throttle and steering servos adjusted as was using all the plus trim just to get it somewhere near but not good enough,took some time to sort out but we got there.

Engine all tuned and it goes like stink,am loking forward to the morning so i can put the shell on and use as intended "full throttle" ha ha

Garry
 
Thank you and counting down the hrs :)

Garry
 
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