Peculiar idle problem with Saito 82

Next time you hold it vertically, hold it so that the engine is on top, not the bottom.

Ed Cregger

Nice one, Ed

I try. In fact, my wife says I am one of the most trying people she has ever met.

Ed Cregger

Does the vent tube extend down into the fuel when you hold the thing vertically? If the tank is pressurized when you go to idle you'll push that fuel up into the muffler.

Dunno why it'd stop the engine, unless it's either causing backpressure, or if the tank isn't relieving pressure fast enough, or if the fuel gets into the cylinder through the exhaust when it spits up.

Tim

That is an interesting idea. The end of the vent tube is at the top of the tank probably 30 to 50 percent behind the front of the tank, so when the tank is nearly full it would be submerged. I should verify I only have the problem when the tank is over half full. What first put me onto the problem was every stall turn or spin would result in a dead stick landing but I don't recall if this was always eary in the flight. Your explanation seems so logicical that I wonder why I never see this phenomenon on my other planes.

Ed

Tim Wescott wrote:

Unless it is a well broken in engine, you might also want to look at the low end needle setting.

It is a new engine, I have run a gallon or two of fuel through it. The low speed idle was my first thought - I tried minor adjustments with no change in symptoms. Other than this problem it seems to idle quite nicely . After seeing all that fuel run out of the muffler I started thinking this may not be a problem with the low speed idle setting because I assume the fuel was being sucked into the cylinder through the valves..

Ed

Six_O'Clock_High wrote:

Problem solved. valves were ever so slightly out of spec. After adjusting the valves - problem solved. A big thank you to Ray Gareau for his suggestion.

Ed

Ed Smega wrote: