[QUOTE

I am having trouble getting it to run right. I live in Denver at 5400 feet and so altitude may be the problem, which is, when the engine spins up to high RPM (or tries to..) it QUITS and then is flooded. So flooded that it takes several minutes before it will even THINK about starting again.?[/QUOTE]

Thanks for the pictures. Are you using a HOT plug like an A3? A8 won't take the heat. Have you tried a new plug? With tuned pipes, they can break the filament, yet still work. A broken filament will start and run, yet not hit RPM. Because the filament is broken, the engine floods at the higher RPM. Then the glow plug isn't good enough to get the wet plug hot enough again to start. You said that it will reach full throttle without the pressure line. I bet that you aren't getting the same maximum RPMs that you will get under pressure. Change your plug, even if it lights. Also eliminate the in-line filter. I quoted things from the manual.

http://www.dubjett.com/documents/INSTSJ40-2017.pdf

Quote: YOU MUST HAVE A GOOD GLOW PLUG BEFORE ATTEMPTING TO SET YOUR NEEDLE VALVE. We
recommend Merlin 2003 HOT sport glow plugs – (Red). Others may perform equally as well.


Quote: TANK: Hayes type tanks work well for the Sport-Jett, but any good clunk is OK if you have no leaks and keep it clean. CLEAN YOUR TANK AND EQUIPMENT OFTEN AND USE A FILTER IN YOUR PUMP. If you mount your engine upright make sure that the needle valve assembly is at least as low as the centerline of the tank (this may be impossible). If not, turn your engine sideways so the engine won't have to draw up hill. ABOUT 80% OF THE TROUBLE CALLS WE GET ARE ULTIMATELY FOUND TO BE TANK PROBLEMS.