solafein

Jim:
Sorry about the off topic thing.

Bill:
I am getting a little fed up with my 91 dead sticking on me whenever I let it idle too long. I was attempting a knife edge spin and couldn't get the move down. The gentleman who is showing me how to do 3D tried it and the engine died when he chopped the throttle and started the rotation. It will idle for about five seconds on the ground, sputter and die. No issues with igniter installed, so I changed the plug, no joy. The transition to higher throttle is excellent. To keep it from puttering out I have to set the idle so high that the plane will not set still on the runway, asphalt. Am I still too rich on the bottom, or do I have another gremlin?

Data:
Funtana S 40
Saito 91
14X5 Pro Zinger
Cool Power 20%
It does the same thing on Omega 15%

Thanks

Hobbsy

My Feedback: (102)

Sol, it sounds like the LS needle is still too rich, there is a way to check this out. With the HS needle at absolute peak the midrange between 4,500 and 6,000 rpm will be smoky and rough but will lessen as you get closer to the HS needles range. Turn the LS needle CW 1/8th turn at a time until you it speeds up a little, testing the transition after every other change. When I think I'm close I like to jab the throttle open a few degrees, if it is too lean at that point it will hesitate but will not kick the prop off, merely open it back up 1/8th turn. Of course while doing all this you need to be reducing the throttle opening to compensate for the better mixture causing it to idle faster.

Plum Crazy

My Feedback: (5)

Hi I just received my first Saito yesterday. Its a 72 and its going in a GP piper j3 cub that getting pretty close to finished. I have a can of Powermaster 15% it says on the can that it is 18% oil and its a synthetic / castor blend. By going to the powermaster web site and if i'm right in guessing that this is their sport fuel then it should be 2/3's synthetic and 1/3 castor and i would need to ad oil to this fuel to break in my 72 right? Or should i just pick up some other fuel? I know of Klotz and Blendzall brands of pure castor bean oil, are one of these brands what you guys would reccomend for adding oil to fuel? I guess I'm a little confused. I've read every line of this post and i need to thank you guys for the info on Saito's it's a beautiful engine.

Hobbsy

My Feedback: (102)

That fuel will be perfect, I run mine on an 18% 80/20 syn/castor blend and they are healthy.

William Robison

My Feedback: (3)

Sol:

I agree with Dave, because you say the transition is good. If you were too lean it would at leasty stumble, maybe even, as he mentioned, kick the prop off.

My pet way to get the LS roughed in has been adopted by many, with some it has almost become a religion. And it's simple.

Pinch the fuel hose shut while running at idle. If the rpm comes right up it's too rich, if it dies immediately it's too lean. You want the rpm to rise sllightly and then fall when you pinch the hose. At that point do your final adjustment check by seeing how the engine answers the throttle.

Bill.

Kmot

My Feedback: (24)

All I have ever run in my Saito engines is Powermaster 15% sport fuel. In fact that is what fuel I use in every engine I own. Your Saito will thrive on this fuel.

I do have some Powermaster "YS 20/20" blend I purchased but as yet have not run it. I understand from Bill it needs to be "castored up" a bit.

carlbecker

My Feedback: (3)

I have a Laser 120 that idles very well with onboard glow. I had a problem with the onboard glow so I flew it without. I had to set the idle higher by a good deal. Finally I removed the cowl and set the high then low end for good transistion. It was much better. I fixed the onboard glow and now I can get a real low steady idle for extended periods. You might want to consider an on board glow - C-tronics makes a good one at a good price.

Carl

Jack211

Bill, thanks.

You said: "With the valves loose the idle might be a little smoother, and a little less power on the top end. In either case there wont be a big difference, but to get that lat bit of power the valves can't be loose. Also, when the valves are loose the valve train components hammer, this accellerates cam lobe wear, it can even gouge pits in the ramp of the cam lobe. See picture."

With my 82a on the Twist, after several gallons of fuel, I tried to set the LSt down again, trying to get an idle where the plane wouldn't walk away from me. [I could change out the 13 x 8 prop, too, but bigger, even at lower pitch, may have the plane walk away from me anyhow.] That bird has trouble with resonant vibrations because of large spaces of unsupported Ultracote, but when I got the idle down, there seemed to be a definite "knock," as if someone had taken a light, flat board and hit the plane, every other second or so. So I set the idle, on the radio, just above where it made that knocking sound. That couldn't be "valve train components" hammering, could it?

Jack

William Robison

My Feedback: (3)

Jack:

No, that's not the valve train. I suspect you're getting the occasional instance of preignition causing the noise. Go a hair richer on the LS, see if that helps.

With an 8" pitch on the prop and a light airplane you might not get a good rest on the ground. Remember that 8" pitch is blowing its wind more than 15 mph even when it's down to 2K rpm. Just might have to go to a 6" pitch. That will lower your top speed, but it will help acceleration from lower speeds. And its wind at 2K rpm is almost down to 11 mph.

Bill.

Dennis H.

Hi all, is it possible, to take the carb. off On my Satio 100 and turn it around? Where the high speed needle valve, is faceing the other way??
Thanks
Dennis

William Robison

My Feedback: (3)

Dennis:

Yes, it's reversible. Only in the smallest Saito singles can the carb not be reversed.

Bill.

jojobajim

Same problem with 56, runs well and idles great, but still needs a diaper after trying an extension on the intake venturi. I may have a fuel leak out the front bearing. If so, does this indicate a bad bearing/seal, and also excessive blowby on the piston? Thanks for any input. Who is the Saito repair rep? and what might such a repair cost?

w8ye

My Feedback: (16)

I have a couple of juicy Saitos. Doesn't seem to hurt their power or mileage. The oil just goes out the front instead of the rear.

Enjoy,

Jim

Edge 540

I just joined club saito with a nice new saito 82!!!!! Anyone ever NOT want to run this thing? It is to nice to get dirty!
The book recommends several different props in the 11-13in range. What do you suggest? My ground clearance wont allow a 14"er.
I also want a good compromise between 3d and precision flight. I want to be able to hover, but still get some good speed out of it.
thanks

w8ye

My Feedback: (16)

If 14" is out, then a 13-8 is more like it. But 3D will not be the best in the world?

Enjoy,

jim

daveb86

My Feedback: (4)

I only have one .72 in my funtana But i love it to death and will Never own a different brand motor. Workin on gettin a 100 for my baby! :-)

Jerry C

My Feedback: (6)

Hi
I have a Saito 125 how do I join?
Jerry

Hobbsy

My Feedback: (102)

You just did. Let us know how the 1.25 is, mine is close to being broken in.

Jack211

Jobob, I've had the same problem with my 82 and 1.0:castor everywhere, streaming from the firewall. My 4 cycles have been my "dirtiest" planes in that regard. In this thread, somewhere above, the fix was mentioned, I believe. When that Saito is running, some fuel sprays OUT of the carb to the firewall and runs everywhere. If you can SEE the carb on the bench, rev it up and down. You'll see a fine mist, maybe more, being sprayed around in the prop wash.

The fix: see Horizon Hobby for SAI50GK93, called a velocity stack. The item mounts on top of the carb opening and helps keep that mist going INTO the engine. I haven't tried it yet, but will. Seems it would help with fuel consumption, too.

Bill swears by it. And when Bill swears, I listen.

Jack

Jack211

Sorry, Joe, in the morning I don't read so good. Did you say you TRIED the velocity stack ["an extension on the intake venturi"] and it didn't help? Bad news. Maybe I'll save the $6.75.

Jack

Hobbsy

My Feedback: (102)

Saitos do not spray fuel from the carb equally, my .50 doesn't do it at all, my 1.25 does not appear to do it, the 2.20 has a very long velocity stack. The engine in the picture is sitting at the beginning of the compression stroke, as you can see it obviously has lot of overlap.

Jack211

Bill, thanks again, an excellent succinct explanation: <<Remember that 8" pitch is blowing its wind more than 15 mph even when it's down to 2K rpm. Just might have to go to a 6" pitch. That will lower your top speed, but it will help acceleration from lower speeds. And its wind at 2K rpm is almost down to 11 mph. >>

Now, is there a good explanation somewhere of how low or high you can go with a particular engine in re: prop size? Elsewhere I read recently that for 3D applications, put the longest prop with the smallest pitch the engine will take. I have a 61 OS FX with a Master Airscrew 13 x 5 on a Twist. It's perfect (with up to 25 minutes flight on an 11 oz tank; 82a gets only 11 minutes, same kind of flying). When I ordered another 61, a SuperTigre, the specs didn't "recommend" anything over 12 x 7--but I want to put that 13 x 5 on it. I e-mailed a tech at SuperTigre and they said a 13 x 5 may be used but "no guarantee" of performance.

I overprop my SuperTigre .45s all winter with an APC 12.25 x 3.75. It takes longer for the .45 to spool up from low idle, but they do, better in the mid and high ranges, and it doesn't seem to hurt them. In summer, hot air, the ST doesn't like the 12.25 (REAL slow spooling up) and I go back to an 11 inch prop.

Will overpropping an engine hurt it? Can I "under" prop the 82a with a 13 x 5?


What, if any, is the relationship between fuel economy and prop size?


Jack

P.S. Sorry to put you to such work, Bill.
P.P.S. No, I'm not. :-)

Jack211

Jobobjim,

One more thought on the velocity stack you tried: did you seal it with a rubber O-ring between the stack and the carb mouth?

Jack

jojobajim

Being on the frugal side, I cut a Dubro exhaust extension to about 2 inches and slipped it over the venturi. Should have been an oil/fuel tight seal. Sure like the way the engine runs and may just have to keep changing diapers! Thought as a Grampa that was over.

Jerry C

My Feedback: (6)

Hi hobbsy
What is the round thing that the outlet fuel line from the Iron Bay is tie straped to?
Jerry