ive been trying to start my jato 2.5 for ages now with no luck. changed plug, cleaned carb and tank, reset tuning back to factory, done load of things with no success.
the fuel is very slow to flow up the line and once it gets to the carb it doesnt appear to go in. iv put fuel directly into the carb and it starts straight away and dies after a couple of seconds
anyone have any idea of what may be wrong, any help appreciated

Try putting your finger over the exhaust outlet while you are turning the engine over with the EZ-start, you should see the fuel going into the carb a lot faster than when you just turn it over.  If this is the case, your fuel system is probably sealed up good.  If you don't see the fuel rushing through the line when you do this check your fuel tank for cracks, the fuel and pressure lines for and leaks and the tank o-ring for a bad seal. You can take the tank off and put it under water while blowing into the pressure line with the outlet capped off to see if you see any bubbles.
You may want to clean the carb again and put a filter inline before you try to start it again in case there is some junk floating in the lines (and replace the lines as well).
Also, sometimes the factory settings don't work for the environment.  Try going 1/2 to 1 turn richer on the LSN to see if it will fire up.  When it's cold out these motors need a lot more fuel to get going due to the dense air.</p>

I think you have a fuel restriction. If you put fuel down the carb and it starts, then dies its burning off the "priming fuel" and not pulling enough or any fuel to the carb. If you have a fuel filter, take it apart and clean it. I'd also suggest pulling the high speed needle assembly out of the carb body and verify that the holes in the needle assembly are clean. If you use fuel with castor oil in it and the model sat for some time I'd bet the castor congealed some and plugged a passage somewhere. I've had it happen.

Its very possible it may be clean and it just needs to be primed better. If the fuel flows slowly to the carb with exhaust plugged and turning the engine over there is a restriction. With a pullstart, there should be fuel to the carb within 1 or 2 pulls. With the EZ Start, it should only take a second for fuel to get to the carb. When I prime my engines, I turn the engine until fuel reaches the carb and turn it over 1 more pull or one more quick click of the electric starter. (I dont plug the exhaust, I blow through the pressure line to the tank)

thanks for the help. i put my finger over the exhaust when priming with the ez start but it still take a long time to reach the carb, the fuel tank o-ring is in good condition as i had the tank out recently. fuel lines seems sealed up ok as when i take it off the carb and crank it the fuel flows out easily but ill look more into it, i think its a carb problem but cant figure out what. ive tried running it richer as it was cold but still no go. the fuel gets to the carb after some persuation then cannot get any further, ive removed my fuel filter to remove that and ive took apart the complete high end and low end needles and cleaned them in nitro fuel. it sat up for a long time but i cannot see any gunk in the holes, might try new fuel lines if that fails, jato 3.3 engine 

If you didnt soak the main body of the carb, I'd suspect your problem to be there. I suggest tearing the carb apart - every single piece and soak in fuel for 10 minutes or so and blow through every orifice on the body of the carb. There is a fuel restriction somewhere; I think replacing the engine without fixing the problem sounds rather brash.

Make sure the pressure fitting on the muffler isn't plugged if you haven't already.

You should see a huge increase in the speed of the fuel flow when you put your finger over the exhaust, you may be looking at a worn out engine.