Odd fuel problem on new D8T/Apache hybrid

[Dirk Squarejaw]

I have what is basically a D8T with HPI Apache bodywork and suspension. The rolling chassis, engine and pipe were bought new. Only used parts are the electronics which aren't causing this issue.

The engine is a Sportwerks .26v2 with roto start and a Thunder Tiger Efra 2035 header/pipe combo. I've got fresh O'Donnell fuel, new plug, and charged igniter.

To get fuel to the carb, I have to plug the carb with my thumb and crank the roto start. Here is where it gets weird:

If it starts (it's never stayed running more than 30 seconds), the line from the tank is instant bubbles and it goes lean and dies.

If it doesn't start, when I let off the starter, the fuel doesn't just flow but shoots quickly back into the tank.

The only thing I've tried so far is changing out the crappy factory fuel lines. Any suggestions are greatly appreciated! I've had at least a dozen Nitro cars and a swamp buggy and never had this issue.

 

[Alexander_0_1]

Did you try a different fuel tank?

 

[Rolex]

I'm guessing the LSN is either clogged or not opening enough. There's got to be a buildup of pressure at that point to make it go back to the tank.

 

[Dirk Squarejaw]

Found the problem....

I noticed it wouldn't prime by plugging the exhaust and after close examination, I got too much loctite in the hole where the pressure tap screws in. Starts up and runs now. Trying to get it broken in now.