Saito 180 cannot richen high speed mixture?
 

I cannot seem to richen up the high speed mixture on my Saito 180, although it's like 4~5 full turns out from fully closed. It will run adequately at 4~5 turns out, not lean, not rich. But it makes me a little nervous. I even tried the oscillating pump, and it still cannot richen up. My tank is at same level, just 7" behind the carb. My idel screw is about 3 turns in from flush. I did open it to flush and try the high speed, but it didn't make a difference. I have about 1 gallon through already. Does anyone else have this problem? :confused:

By the way, how much can I turn out the oscillating pump? They say out is more. But is there a dead stop when I turn it out the max turns, or will I just unscrew that thing altogether?

Saito 180 cannot richen high speed mixture?
 

I have the same problem. It got a little better after I changed all the pipes and fuel clunk for a bigger ones. Now is on the rich side only about 150 rpm from peak and about 5 turns out. I am little nervous also, but my tank is bellow the carb. and I think is all I can do for the moment. I hope it is not too lean.
First, I recommend you to check if your fuel tank clunk an all pipes are big enough, and if there is not a point were it get smaller than 2mm. At least, after I changed all the pipes, it is running better.

Saito 180 cannot richen high speed mixture?
 

If you can't get the engine to run sloppy rich, you either have a restriction in the fuel delivery system, or there is a major air leak in the system. In either case, you need to resolve this. It doesn't really matter how many turns the needle valve is out as long as backing it our further will make it overly rich giving you the ability to tune the engine properly.

John

Saito 180 cannot richen high speed mixture?
 

The thought of 5 turns on main needle is scary in itself. My Enya 155 runs rich at slightly less than 1 turn. Now that's the other extreme. I noticed the muffler pressure tap doesn't have whole lot of pressure. When I blow on the muffler from the engine port, I can sense very little air pressure exiting the pressure tap. I blew on the Enya muffler, it feels like 1/3 of air is going out of that tap.

Saito 180 cannot richen high speed mixture?
 

Try richening up your low end needle. If its too lean it could affect fuel flow at higher speeds.

Saito 180 cannot richen high speed mixture?
 

This is exactly why it really doesn't matter how many turns out the needle is. Every engine can, and will, be different. As long as you can properly adjust the engine from sloppy rich to lean enough to fry it, you can properly set the needle for nearly any condition.

John

Saito 180 cannot richen high speed mixture?
 

THe Saito 180 runs the best (at 4-5 turns out "RICH") until it is fully broke in. BUT... you should be able to open the needle and get it dog rich! Yes the pump may be on the lean side, or you are using small or medium fuel tubing. If the low end is too lean then it would'nt run. You should still be able to richen the hi end to the point where it dies. I'm in the process of breaking in 2 180's and both are being different animals. So each needs its own attention.

Saito 180 cannot richen high speed mixture?
 

The Saito muffler will have plenty of pressure... what you noticed is a difference in airflow VOLUME when comparing one muffler to another... caused by a smaller nipple on the Saito probably...

This doesn't matter since you only need to flow the same amount of exhaust gas into your tank as your engine comsumes fuel... so even the smallest hole will be enough to flow something like 15 oz of gas in 15 minutes...
Do you get the picture?

When your 180 starts to comsume over 1 gallon of fuel per minute... THEN you need a bigger nipple....lol...:p

Saito 180 cannot richen high speed mixture?
 

Make sure you are using LARGE diameter fuel line (1/8" i. d.), drill out your fuel tank klunk to 1/8", and use a large fuel filter (same minimum i. d.). I am guessing this should allow you to richen it up to your hearts content. The 180 is a thirsty engine.

Saito 180 cannot richen high speed mixture?
 

Hey, I fly at Flying Pilgrims. Are you one of the club officers? I am Sean by the way.

I set the oscillating pump 2 full turns out from fully closed. Then I raised the main retainer 3 turns out from the carb feature, which brings the needle 3 turns away from spray bar. Now it runs w/ needle 1 1/2 turn out.

The downside is that with oscillating pump, the transition is a little slower. I suspect that the midrange is rich, because midrange rpm is only slightly lower than full throttle rpm, thus the oscillating pump pumps almost as much fuel into the engine at midrange.

Saito 180 cannot richen high speed mixture?
 

Sean,
I'm a member, but not an officer of the club. I've probably seen you at the field before! I'll look for you this weekend.

I'm not familiar with the oscilating pump (is it a perry?), but it sounds like you are in fact making it rich at midrange by pushing too much with the pump. When you open it up to full throttle, it needs a lot of fuel, and I suspect your line diameter will not keep up with the demand for flow. Are you using standard diameter lines and tank clunk? That is the first place I would look. There is a great website for Saitos I'll find and post as soon as I can find it. It addresses the need for the large tubing etc.

See you at the field,
Jeff Keefer
:)

Saito 180 cannot richen high speed mixture?
 

Sean, check out the info on fuel tanks along the left hand menu, then scan down to where they talk about the 150 and 180.

http://saito-engines.info/

Hope this helps.
FP