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Fuel back-pressure

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nitromidget

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I had my evader finnally running without breakin for like 30 mins. Fun 30 mins tho i had my ramp out and was launchin it off of it but then since i only got a quart of fuel when i bought it i ran out. Well anyways i noticed afterwards i had no backpressure (dont ask how) i tried re-attachin the fuel lines making sure my manifold was actually connected (1 screw vibrated almost off last time i drove it) and it was so... i dont know should i try new fuel lines and will regular fish tank lines work? (always looking for the cheaper way) Theres no rush tho cause its outa commision this week anyways for fuel, untill i get paid
 
Thanx, thats what I thought. I just wanted to make sure, any suggestions on my problem? Seems like i have an air leak.
 
I would also check the tank and fittings to make sure there are no defects or breaks.
 
Yeah i tried that too i pulled the pullstarter while holding down the top of the tank and pluggin the tuned pipe, nuthin :shrug:
 
I must be missing something here. You ran it, you ran out of fuel, and now you are trying to prime it and you are getting nothing.

How do you know you have a problem, if you are out of fuel?
If you need info on a problem, we need info as to when, where or how you realized that something was wrong.
 
ok sorry bout that i had about a 1/4 tank left and thats it i just put the excess of the quart bottle of odonnel just because i wanted to see if i had back pressure (dont ask why it was just one of those things i tried to prime it and nuthin so i spent like 30 mins tightening stuff up and reconnecting lines) i realized somethin was wrong when i had to pull the pulstarter like four hundred times really fast to get the fuel half way up the line then i stopped and it went right back into the tank. And its not needed at the moment but when the time comes and i have the fuel and theres no way of priming it....So id rather get things fixed be4 i try to start it up again
 
Take the pressure line off the muffler, hold down the fill cap and blow through the pressure line while pinching the fuel line before the carb. Do you notice a leak. It's not hard to get a small crack in a fuel tank or a bad seal around the cap that will effect pressure.
 
Also, if you only have a little bit of fuel in it, the tank may be absorbing what little pressure your pumping into it when pulling the starter. If you had a bump start, it may be able to keep the RPM's high enough to compensate for the empty tank.

Check what you can check, but don't be surprised if it primes with a full tank. With the tank full, there's no air in the tank to absorb what little pressure your creating when pulling the starter.

Just a thought.
 
Wow now this is why i use this forum. The most experienced ppl giving me the best solutions and tests to figure out my problem i will go try that now and i bet when full it probably will work but... I'm just over thinkin right now oh and a couple of newbie questions... the glow driver... oh what a tool lol I'm not sure how you guys do it but i can take the glow plug out with the driver and then it some times it gets stuck in the driver and it is immposible to put the glow plug back in with the driver because hwen i put the plug in the end of the driver i sinks all the way in and no threads show and sometimes i have to use my igniter to get it started and then the glow driver. Any quick and easy solutions?? and tuning... i read on this one site that to tune the low end needle you let the car idle for a minute to see if it stalls out on ya and then if it does listen to how it stalls out like if it revs then stalls (lean) or bogggs and stalls(rich)... Does this method actually work? and is it high speed before low speed when tuning?
 
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When you get your fuel, get back to us for your tuning issues. It's always best if we tell you, then you try, then give us the results so we will know what to tell you next.
 
Normally, it's high speed then low like you said for tuning. A minute of idleing will get you in the ball park. The way these engines are designed, prolonged idling causes them to load up if it's tuned correctly.

The best thing to do is to get it to idle for a little bit. Do a few high speed passes. If it gurgles on high speed your probably running rich. If the sound of the engine kind of changes to a higher pitch on a high speed pass or it stalls/loses power or runs excessivly hot, your too lean. Once you get your high speed figured out, pinch your fuel line a couple inches away from the carb. It should rev up and die in 3-5 seconds. If it dies sooner, your low is to lean, later, it's to rich. Adjust accordingly.

Just remember that any tuning of your HSL will affect your LSN. The HSL not only changes your high speed running, it also adjusts your overall fuel flow. Normally, a dramatic HSN change will require a LSN change as well to compensate. If you lean out the HSN, you will need to richen the LSN and vise versa. This is after you get it tuned correctly of course.

Get a pair of side cutters to gently grab the few threads of the glow plug that are sticking out and pull it out.

I don't know everything and there are many more experianced people here. I just post what I've tried and what works or doesn't work. I've only been in the hobby for a couple years. But I've read quite a bit and tried quite a bit in those couple years.
 
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I agree with Olds97, but I'd like to add that I switched to Dubro neoprene fuel line. It's relatively cheap, and much stronger than silicone fuel line (doesn't get sloppy at the connectors). You usually can find it at the LHS where they keep all the Dubro hardware. It's black, and the same size.
 
good idea on the dubro lines ill be getting some etra fuel line nex time i go to the lhs because when i installed the fuel filter i cut a little bit too much out, not enough tomake it lose its connections but enough to grab the cooling head. Thanks for the long tuning post olds. :clap:
 
I was too lazy to search. I've read most of this stuff here and there either in this forum or a couple others I keep tabs on.

Good luck. Richer may eat plugs more often than perfect settings, but it will help your Piston and Sleeve last longer.
 
thanx ill be runnin her all weekend and this time I'm gonna get a gallon of fuel to last me longer so hopefully if the "piece" doesn't break on me i can get it tuned up.
 
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