shaggy48

So I was flying my 60 size yak with a saito 100 this past weekend. Great couple days of flying, but I've a few questions for anyone familiar with the Saito 100 or maybe it relates to all four stokes. I've noticed that at about half throttle I'm getting a lot of smoke. Seems to run just fine at WOT and at idle but the mid range smokes so much it looks like I'm using smoke. Is this normal? Or am I still too rich on the high end? I love this engine and have been flying it for about 6 months or so. At first I had it running great using powermaster 20/20 but whenI couldn't get that anyomre I changed to wildcat. Now I've gone back to the powermaster since I can get it again. So I had to retune the engine each time. I may not have retuned properly this last time. Just want to get an idea of which direction I should be going. I did have to mess with both the low and high end when I retuned for the wildcat and back to the new powermaster fuel. I'm thinking I"m still too rich but it runs go great at idle and almost WOT I thought I had it right.

Second question: When I'm adjusting the LSN, all I have to do is just insert the screwdriver into the slot and it affects the idle (leans it). I mean I haven't turned the idle screw, just putting the screwdriver in the slot affects the idle. That lets me think that my idle screw is sloppy loose. But it doesn't feel loose, in that its snug to turn. So it's not moving from where I set it. Is this also normal? The engine is in a cowl so I'm going through a hole I've made in the cowl for accessing the LSN but this sensitivity doesn't seem right to me. I'm going to remove the cowl and try to figure this out but again any advice is appreciated.

Last question: So I've made up a little handle (bent landing gear wire) going through the cowl and into the HSN so I can make adjustment. But on my last flight I noticed the thing was sloppy loose. So not wanting to loose it, I loosened the set-crew, reinserted the little handle and retightened it. Well at the end of that flight I still lost the thing. Made another one but it wont surprise me to loose that one after a few flights too. So, whats a good way to go here? There has to be a better way? I don't want to over-tighten and/or strip that little set-screw in the HSN. Anyone know any tricks that might last a while?


I'd post this in the Saito thread but who wants to search though over 700 pages to find a reply?

Thanks in advance.
Shaggy

Hobbsy

My Feedback: (102)

Your LS needle is not loose, the carb barrel is moving to the left when you push on the screw driver, go ahead and turn the LS screw CW 1/8 turn at a time and see how it runs when you remove the screw driver. The midrange smoke indicates that the LS needle is some rich. Your LS needle is actually a sleeve over the spraybar like this.

gjeffers

Last question: So I've made up a little handle (bent landing gear wire) going through the cowl and into the HSN so I can make adjustment. But on my last flight I noticed the thing was sloppy loose. So not wanting to loose it, I loosened the set-crew, reinserted the little handle and retightened it. Well at the end of that flight I still lost the thing. Made another one but it wont surprise me to loose that one after a few flights too. So, whats a good way to go here? There has to be a better way? I don't want to over-tighten and/or strip that little set-screw in the HSN. Anyone know any tricks that might last a while?


I'd post this in the Saito thread but who wants to search though over 700 pages to find a reply?

Thanks in advance.
Shaggy

Hobbsy is right about being rich on the low speed needle, and below are pics of how i made my wire adjustment for most of my planes.
they are knobs off of a old radio i had and some wire pushrod that i JB welded into place.

w8ye

My Feedback: (16)

there is a lot of vibration in this area and the length of your extension plus the weight of your knob are just too much movement,.

See if you can come up with something that weighs less?

shaggy48

OK guys,
Appreciate the responses.  I guess the sensitivity is normal. And you're right it is the whole barrel moving when I insert the screwdriver.   I'm going flying tomorrow morning and will try to lean out the LSN some. I kinda hate to do that because I already have a problem with getting the idle to slow down with that engine because as you know the leaner I make it the faster it wants to run so I'll have to play with the trim as I lean it out.  But at least now I know the excessive smoking at mid-range is caused by the LSN being rich.  So just knowing that is half the solution right?   

As for the HSN knob.  Well I don't really have a knob per say just a short piece of wire the diameter of the hole in the HSN and just long enough to exit the cowl and about a quarter inch bent at 90 degrees so I can easily turn it.  It weights nothing and I'd think is not of any significant weight.  Not at all like the beautiful knob installed by you Gary.   But you're probably right in that it's a combination of the weight and engine vibration causing a loosening of the set screw.   My 100 doesn't vibrate all that much (relatively speaking of course) And when I lean out the low end it will vibrate a little less but I still think I'm in for loosing this thing again if I don't do something better.  I'd hate to resort to having to weld something together like you did.  Don't get me wrong, it looks nice, but I'm surprised that the best we've been able to do is a set screw that is always going to come loose?   Hate to ruin a good HSN by welding something to it, but if it is my only option I may have to consider it. 

Someone needs to make an adjustable length HSN or something. 

Shaggy

w8ye

My Feedback: (16)

I use a bent wire in several of my Saito needle valves and have never had any trouble with them coming loose

gjeffers

ive had not one problem with my extensions and have been using them for years. must be lucky! on my pitts i did wrap some elec tape around the wire to slow the osilation down and i also used red thread locker in the hole, and like i said it has been hassle free for at least 4 years in the same plane on a saito 180.

shaggy48

Well if yours has lasted that long I must not be doing something right.   I may just remove the cowl again and give that a try.

Shaggy

Rudolph Hart

File a narrow flat spot on the wire where the grub screw locks it in.

mike109

G'day

I have been using wire extensions for years on several Saitos and other engines and never had one come loose. If one does work loose, chances are it is caused by a resonance problem.

Try using a longer or shorter piece of wire and/or using a different thickness of wire to set the resonance at a different frequency from the setup you have.

Cherokee Flyer

You might re-check the prop balance also.

L.