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Old 10-22-2008, 08:01 AM   #1
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Default BAD FUEL TANK????

Has anyone ever had this problem ? :
During a recent race, I noticed that once the tank starts to get low, (about half full) If I open the fuel cap to check the fuel level the motor would rev very high like it was leaning-out. When I quickly closed the cap it would idle back down. This happened about two times then went away. I'm running an MRX-4R w/ a Cordoba motor. I also notice that the car would start a race strong, then after about 10 laps the plug would blow,even after I richen it up.

Thanks in Advance,
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Old 10-22-2008, 08:48 AM   #2
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The thing with the tank lid is normal, all engines will do that when you open the tank lid. You're basicaly leaning out the engine because you're releasing the pressure from the pipe, causing the engine to have to suck the fuel from the tank.

ABout the plug, Im not that good with engine tuning, but you might try adding a head shim.
Steven Muller
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Old 10-22-2008, 09:55 AM   #3
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I had a tank that was bad but the motor would cut off when the tank was half full. Changed the tank and that fixed it. Your tank sounds okay to me. May be a tuning issue since it may be running lean and when you open the tank, the fuel supply drops even more which makes it lean to the point that it starts revving up.

The glow plug problem may be a head shim but I would check your bearings to make sure they're okay. My plus 12 started blowing plugs and I found the rear bearing falling apart. Changed the rear bearing and now it's fine.

MINO Racing
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Old 10-22-2008, 04:33 PM   #4
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Thanks for the help guys, I will try adding a shim or two to see if this cures the plug problem. The stock shims are for 25% nitro and that is what I have been using. Maybe this is something that NovaRossi needs to look into.

Thanks Again, Ken
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Old 10-22-2008, 06:48 PM   #5
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I bet your idle mixture is a little on the lean side too.
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