Got the tt pro 46 started yesterday but it wouldn't go above 1/4 throttle without cutting out. I lowered the angle on the fuel inlet down ward to take a rise out of the fuel line and it will now go full throttle on demand. It seems to not want to idle easily now. I have not put even a half tank of fuel through it yet, and the tank outlet is about 1-1.5 inches below the carb fuel inlet. Is this too much? I am not sure if the idle needle is just very rich or if it is not pushing the fuel up like it should. I don't see a way to get the motor lower than what it is already in the world models mark 1 arf. I thought that maybe the idle is just too low, I am running it on the cradle so I am not sure if the idle could come up without her rolling off. I tried my best to find a thread with the tank/engine diagrams but couldn't so any help is definitely appreciated. I am sure I will start many more threads before I get this thing completely worked out. Thanks!

Tank should be positioned in level with the spray bar (center line, regardless of the position of the tank inlet)

For typical suction/exhaust pressure system the drawing Alfred posted should always be adhered to with upright, sideways or inverted mounts this Tank center/carb jet relationship needs to remain the same if many running problems are to be avoided.

The rotating inlet bellows on most TT engines will make no real differance in engine running and it does not matter which direction you point it.

John

I wouldn;t be too concerned about the tank to engine location on your Mach-1. Yes, it is ideal to have everythign lined up but plenty of these airplanes are flying just fine with the tank as-is. It wounds to me like tou have more of an engine tuning issue. To me it sounds rich but that's kind of hard to determine without actually seeing it.

G'day Mate,
You need to run the engine in, some more, try at least a couple of tanks, give the thing a chance to seat the piston, to the liner, then try adjusting the mixture.
Did you think to read the instructions that came with the engine?

Exactly.

Tank height is important to prevent siphoning in either direction... but it does very little to affect tuning.

We actually test tank height for a "worst case" when we perform a nose-up, nose down test.

This puts the tank height way below the engine when properly done, much like the plane would fly when going straight up.

As Chuck indicated, concentrate on your tuning.

Cutting out as you move to transition indicates an improperly set HS needle or too lean on the low end.

If its a new engine, the high speed needle needs to be adjusted in combination with the throttle until you can get it to full throttle. Leave the glow igniter on it until you get it to go to full throttle. Once you get it to full throttle, get it peaked and then set it rich and remove the glow igniter. Then follow the break in procedure.

After a few tanks of fuel you can start worrying about adjusting the low end. The TT Pro 46 is one of my favorite engines, and they are very reliable once you get them tuned.

Brad

take the engine to full throttle and close the needle untill the engine reaches max rpm then turn it quarter of a tern rich. you should now have your engine as close to idle as possible.

Got her running great Saturday and flew it. She has so much power, I may end up being a TT guy if this thing has a nice long life. I was just worried, because my Nitro car engines all idle decently right out of the box, but I can tell these are different animals. Thanks Guys!