I just got a perry pump regulator and it didn't come with any instructions - just a pump/tubing and a pressure tap.

I installed the pressure tap in the back of back cover of my .52 2-stroke that's inverted I'm trying to solve fuel siphoning problems and generally not holding any kind of needle settings either high or low despite being broke in now.

I have a 3 line tank, one line to the regulator/carb, one to the bottom of the plane with a fuel dot in it for filling and anoher left open to the atmosphere. I installed the pump in a handmade bracket (the bracket included would never tighten around the pump to keep it from rotating) above level with the carb and a fuel line lenght of about 2 inches from pump to carb (can't get any closer because of the cowl).

Is the set screw on the pump just control pressure? Or does it control pressure and volume? Also which way does what, in for more pressure/volume or out?

Any tips for setting up my engine because running as installed didn't solve much. It still siphons fuel, top end needle seems to be pretty steady but the low end seems overly sensitive one run and then the next run (about 2 minutes apart on the same tank) it seems like the low end needle is ineffective. Idle below 3000 is sketchy at best and doesn't want to settle down for about a 20 seconds after a run up. In a span of 2 minutes idles goes from 3200 to 2800 and then eventuall wiill surge around a bit and sometimes when you let off from wide open it comes down and gets rough then dies. The pinch test didn't result in an overly rich or overly lean condition (at least to me). Engine ran OK before I inverted it and like I said is well broken in already so idle shouldn't be a problem now.


Help please I'm about to go nuts and I don't want to just start adjusting this and that without having a goal or know what's going on.