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2.5 was running good, not now

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SVTSupermaxx

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Truck was acting up a little bit (engine wise), broke a fuel tank.

Replaced tank. Now when I drive it, I can drive for about 1 min. and the motor cuts off. No high rev, no slow rev, just dies.

I have returned needles to stock setting, richened, leaned, and installed 2 new glow plugs.

Still no luck. I have looked around the carb for possible air leaks and have not found anything. I did find one place where plasic was slightly broken below HSN, but does not go into the carb body.

Anyone have any ideas?
 
check the fuel lines for holes or rips. i check mine by plugging one end of the line, putting the whold thing in water then blow throught the other line. IF any air comes out, there is a whole/rip.Replace them. How old is the engine? may need a rebuild? Are the temps really high?
 
It's got about 1 1/2 gal. in it. Temps are usually about 240, but since the problems, they are hitting 290's.

It sure doesn't have compression like it did. I can turn the flywheel almost effortlessly.
 
the temps sound like there is an air leak somewhere. Was the compression good before you replaced the tank? Did you break the tank you had before from a crash? I would say check again for air leaks. And check all you tubing. Hope some of this is helping.
 
I just checked the lines and no leaks, I"m cutting more as we speak for replacement. It's got enough compression it should still have no problem running. The time it did run I was slinging rooster tails.

Yes the fuel tank was broken from a crash.
 
ur motor might be just getting ready to be rebuilt. it should be pretty hard to move the flywheel but u said taht it moved easily. maybe u should think about doing a rebuild anywayz.

bryan
 
Ok, just replaced fuel line and took for a test drive.

Still not running right, but it's leaking from either carb or around flywheel. Thats where most buildup is. I think buildup close to flywheel, is just b/c of run down from carb.

There was also leaking around pullstart.

This is upsetting. Going to pull carb off again tonight and look harder for tears.
 
Check the carb's o-rings and seals for damage. They make a liquid sealant for carbs that is great. Ask at your LHS and they should be able to point you in the right direction. I'd give you the brand I use, but the label wore off.

As for the fuel build up near the flywheel, that is most likely from the leaky main bearing that TRAXXAS uses on their engines. The TRX Pro .15 (predecessor to the 2.5) has/had the same problem. There is really no cure for it other than constantly replacing the bearing or replacing the engine with a tighter one.

As for the leakage near the pull start, that is coming from the crank shaft where it pushes through the backplate to engage the pullstart. This too is normal for a worn engine. You may want to give some consideration to rebuilding the engine.
 

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