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No back pressure=running lean

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Tarant

Tarant

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I was finley able to get my savy .25 running. and after a few minutes of tinkering I could not get the temps down. I had all needles flush and the engine was reving high enough to engage the clutch 250. I turned down the idle and it stopped the wheels from turning but it was still reving pretty high, so I was fed up. I took off the fuel tube that was connected to the carb and attached the roto start and turned the engine over for a few secounds, and no fuel came out, no matter how long I had the roto start going no fuel was coming out of the line, I cleaned all the fittings, and replaced the line and cleaned the pipe. but it still had like no back pressure.I am guessing that if their is very little BP then not a lot of fuel would be getting to the engine causeing it to run lean.

I took out the uniflow cause I thought that was causing problems but no luck.

anybody have a idea of whats going on. I am so fed up with this damn engine.
 
did the engine sit for i little while like a month or longer?, my bros buggy did the same thing it wasn't getting fuel so i took the carb off and blew in the fuel nipple cuz i think something or some crud had built up in there and after that it worked not sure if this will work for u but just trying to help.

actually nevermind i just remembered u saying that you took the tubing off and fuel still didnt come out so sorry maybe one of your needles on the fuel tank or the exhaust is cloged I'm not sure, hope u find the problem.
 
look for cracks in the tank or in teh fuel top. a bad seal there would cause this.
 
Done, I put the tank into water and blew air in to the pressure line no bubbles any were. the Problem is I have no back pressure coming from the pipe, like the hole in the stock pipe is to small or somethin
 
you did cover the stinger while you turned over the motor right??

your only gonna get fuel out of it if you cover the stinger..

the engine isnt spinning fast enough to make back pressure unless you cover the stinger..

but it does sound like a clog or air leak.. i would take your carb apart and clean it and replace the lines set the carb back to default and try again..
 
It could be a split in the header/exhaust coupler or a header gasket on the engine that is shot. I've had both of those cases before. If there isn't a good seal, your not going to get crap for tank pressure.
 
I put some grease on the tank seal. and cleaned the carb very well. And know it runs great at temps of around 250, i was trying to run the engine at 220 and it wouldnt run for long,
 
Did your motor make a weird burbing noise when it flips over? I am having the same problem. My motor is running hot like 300-317. I am really frustrated with it.
 
it because you are running way to lean, and the fuel is boiling before it gets to the engine. go to factory settings, all needles flush and tune from their
 
I have all my needles flush and I temp it at 280. When I jump and land upside down and then I flip it back over the motor starts burping and then the temp gets really high.

I think I am having the same troublo you have.
 

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