mattxxx-nt

i was oud driving my xxx nt sport today. when i started it, it backfired like mad!!!

all the flames were 3 inches or longer. what does this mean???

Platinum_Racing

The engine is either too rich, your trying to start a hydrolocked engine, or there is insane blow-by.

Remove the glow plug after cleaning the area around the hole, and tip the car (Which has no fuel in it's tank) upsidown to drain the fuel from the crankcase. re install the glow plug and try again. If the problem persists, lean out the high speed needle about 1/8th of a turn and try again. If none of these things happen come back here and we can figure out a better solution.

Good luck!

mgtman

http://www.rchobbies.org/cars_eng-tuning.htm
http://www.rchobbies.org/engine-tuning.htm
these might help for what platinum said

1fsttraxxas

How can I get my car to backfire like that? That would be killer!!!!!!

mattxxx-nt

i re tuned it and it still bach fifes and it wont start any more

ALJR

iTrader: (10)

what kind of fuel are you using? 101 octane?

Crim3Wav3

iTrader: (8)

DUDE...these engines DONT shoot flames out of ANYWHERE! are you making this up or what????

SpeedBump57

I would think an ill running engine with alot of blow bye could do some thing like that. I have seen engines backfire and then run backwards, very strange site to see.

GregH

try a fresh glowplug.....

I've started my engine before and it started run backwards. I just bump it once on the box and it's running right again.

WheelNut

iTrader: (5)

Yeah dude are you even running nitro in the thing?

JPMSRacing

iTrader: (2)

Lets think how an engine works, backfire is from fire in the cylinder when the exhaust opens up with an over kill in fuel. 2 cycle engine with a backfire is bad. I would assume the rod or rod bearing is damaged not letting the piston travel upward enough to seal off the exhaust port and the the fire is bleeding by the piston out the exhaust. Or some how your jug has turned, head loose, and the timing is out of wack between the intake and exhaust. Anyway, I wouldnt try to start it again till the engine is torn down and inspected, if you backfire into the crankcase and out the carb, the front seal or the crankcase will be damaged.
PS make sure if you are using a roto start or start box that the battery is plugged in correctly. I have started my savage backwards when my boy reversed the polarity on my roto start. It is scary and freaky.

W.E.D.Jim

iTrader: (17)

Alcohol flames are not visible to the naked eye......


...Jim

5thscaleracer

iTrader: (22)

it is possible for the exhaust tho throw down some flames, blue flame not your typicall yellow.

It has happend to me at one time working for a hobby shop. Customers Crappy car Duratrax Street Force of CRAP had a hard time starting, i check all the standard stuff, needles, fuel clog, bad glow plug etc etc...

every thing checked out good started to tug on the Crap Starter engine pop and i didn't think much of it. I pull again Engine starts back fires, flames on the glass counter then motor stalls. I stear at the flames for a good 20 seconds trying to figure out if it's even possible. put out the blue fire and try it again. poof 2 times in a row!

tried for the thrid time and nothing i was able to tune the motor and the customer is on his way but that was the first time i saw a back fire and flame form a nitro engine.

there is always a first for every thing!!!

Jhyten

its so fast its shooting flames sitting still!

bshack

iTrader: (2)

This is why RTR's are killing this HOBBY!!!!!!!!!! You should have proper knowledge of how to tune and operate a nitro engine before you even pull the cord!!!!!! I've raced for 18 years, and only 3 out of the last 18 have been with any sort of nitro car. I spent many hours learning to tune motors, research each powerplant, and then testing them. Every summer, I'll attempt to help new drivers with their cars and how to operate them, however, if you cannot find help at a track, or at a hobbyshop with TRAINED pro's, give up on the nitro thing before you get yourself hurt!!!!!!