engine running bakward

[isaac3636]

maybe someone can explain this to me. the last time i went to the track the first time i fired up my p3 it took off backward . i know that i didn't start it that way. i shut it down and fired back up and everything was fine . then a few days later same thing . does anyone know what could be causing this ?

[jaylude22]

I've never heard a conclusive answer as to why this happens with the car engines. I know a rich idle or low speed mixture with a heli engine will cause it to start in reverse, but I don't know if that is the cause for a car engine as well. I know I've had car engines start that were very rich but they never started in reverse. I'd be curious to hear anyone's conclusive answer to this riddle.

[z3usX5]

All i know is if you get the polartiy on the starter box wrong it will cause this.

[J_Bone]

All i know is if you get the polartiy on the starter box wrong it will cause this.
More than likely, it's the starter box wheel running in the wrong direction. I've done it before myself and have seen it done by others.
I have seen one go back ward some how with the starter wheel going the right direction. The only conclussion I could come up with is, maybe the fly wheel got bumped just at combustion time and some how knocked it to go reverse?

Issac,
What method do you start your engine with?

[AZRCaddict]

I would say it was the starter box too

[TWeatherholt]

This happens mostly on new high compression engines. The cause of it is that every now and then the instant the car fires you lift it off the box it will sometimes be spinning soo slowly that it will reach near top dead center but not have quite enough momentum to carry it the rest of the way over top dead center and the compression will push it back the opposite direction and fire at just the right time to keep it running backwards. You can just shove the car back on the box while running backwards and it will start running the right direction. This seems to happen to me most often the 1st time the engine is started for the day.

[scoobie]

I think its a roto start...and the motor has seen some fuel.

[rcguy68]

Another heads up to a new guy if you rebiuld your diffs and install them backwards in the housing and firer up the car the wheels will turn backward making one think that the motor is runnig the wrong way.
This isnt possable with some cars though.

[z3usX5]

hmm never thought of that one. Good to know.

[isaac3636]

it is a roto start and it does have 6 gallons through it .hasn't happened again so who knows thanks for all the replies :thumbs:

[scoobie]

After what TWeatherholt said, I thought about it...I wonder if a low charge on your rotostart battery could do the same thing as TWeath described?

So if it happens again, try bumping it with your rotostart...tell us if it works

[AZRCaddict]

hmm never thought of that one. Good to know.

Yeah, Kyosho chassis's have a notch in them for the diff so it's impossible to do it.

[scoobie]

+1 for Kyosho! I never knew that, LOL....

[rjmods.net]

did you change diff fluid .before running your engine again for the first time.your diffs could be in wrong ,it will run backwards if they are?:confused:

[rjmods.net]

little late maybe all read more next time deeuueer:shoot: