*** NEED HELP BAAAADLY***
 

Here is the problem, My buddy's 1/8 scale runs good for 2 min and then just richens up so bad the car wont even move. If the car is held up in the air and you pull throttle smooth it works fine if you hammer the throttle it richens up & bogs down. We have changed everything that we can think of, here is what we have changed.

-2 different motors Motors
-Carburetors
-changed fuel lines many times
-different fuel line lengths
-used pressure chamber
-fuel tank
-clutch components
-clutch rebuilt multiple times by different People

make sure the o rings on the high and low speed needles are fresh...if there easy to turn they tend to vibrate loose=rich

It's doing this with two different motors? That's weird. What motors?

About the only things you haven't changed are pipes and fuel.

Also, if this is a Mugen that's a common problem. Lean it out a bit and tune it on a half tank. If it's then too lean on a full tank, richen the bottom, tighten the clutch, increase clutch gap.

That happend to me once, take off the pipe and shake it next to your ear. I bet the bufle(sp?) came loose, when it moves, your motor goes rich. If its loose, you will hear it when you shake the pipe. Also, what pipe is he running?

Thanks for thr tips we will try them out later today

Sal,

I saw something like this once with a pipe that had a partially blocked pressure fittinig on it... the guy used JB weld on the threads to keep it from ever coming loose, but some got into the fitting and had it almost sealed off... we'd start the engine, tune it, then after a minute or two of running the pressure slowly built up and kiiled richened the mixture. Try blowing thru a pice of fuel line attached to the pressure fitting and see if its clear...

Another thing to check is the fuel tank cap... if the spring doesn't close and seal it on its own, it can leak pressure, but as the car runs, the engine vibration can eventually let the spring shut it, and then the seal finally lets the pressure build up and you're rich...

Gonna be at Floyd Sunday?

You changed engines and everything else except the pipe. I had a pipe that was brand new and none of my engines would run with that pipe. I cut it open and found that the baffle inside had only one hole in it, the rest were never punched out. Your problem may just be a bad pipe.

Well after looking in to the pipe situation it ended up being a loose baffle after changing the pipe the motor ran fine THANKS for the help.

Had that same problem years ago, man is it frustrating!! You expect a certain level of Quality Control from these pipe manufacturers but it seems everyone will have this problem sooner or later.

Yes it was very frustrating problem started at the end of last years season cost my buddy some races, He was ready to sell everything. Well I was always told you learn something new everyday. Live and learn:)

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Does anyone know of a track i can race my cen nitro car near stevens point, wi. or a link for track locations? Thanx.