Glowgeek

Here's my thoughts on cooling, ones I have had great success with. It's not so much about where the hot air in the cowl finds its way out, it's more about forcing air over the cylinders (baffles) and then providing a low pressure zone with an Air Dam of sufficient size to evacuate the hot air. In many cases just having cutouts to exit hot air is insufficient. The hot air needs to pulled out of the cowl. The Air dam in the second image provides the low pressure zone and all the more as the airspeed increases.

Glowgeek

Classic David practice, he rarely peaks engines in his vids.

Hyjinx

Yep
You betcha! watch out Hobbs, this subject could co-op club Saito lol. I am following these threads with great interest. The three cylinders are the pinnacle to one and a paria to another. My only initial comments are sort of overly simplistic. Yesterday I spoke with Dr Vogelsang about last minute instructions for my Moki 257 ( I am about to first run. ) His highest prioritys for me were finger testing each cyl. (Spittle on fingertip) psssssst. Each exhaust tube and Forget Heat and smoke testing. (As Dave here has mentioned here) test any design ice and temp variation are present and considered insignificant by manufacturer. ( his statement to which I agree)
Known hesitation and flat spots can be present in radials also and be normal. Lots of moving parts and balanced weights working fast. These engines do not inherently spool as fast as say a hc single and that is an unrealistic outcome without perfect tuning and calming of " hot rod" mentality. These things may do that work but they are going to be frustrating if folks intend to do 3d style super fast response operation.
The doctors other priority was slowing the servo down to match the Moki s ability to efficiently optimize the the fuel that is being so quickly forced into the fire. (Really more important with correctly atomizing the gasoline fuel. ( Not as big a deal when literally pouring raw methanol into a tube and spitting it into another tube)
As I said, pretty simplistic thoughts, but they carry a lot of weight on these funky little scale radials. Imho.
Last thought. Why didn't Satio incorporate the brilliant design of the early R5. The motor incorporated a impeller style fan in the cavity now housing the intake " tubes" machined into the part.
The turbulent intake of fuel and supercharging effect seems to have made a big difference. (common on full size types)
Never seen or heard of this complaint with an R5. And mine runs flawlessly without obg. But my Fg450 R3 does too. It hesitates enough as it spools to make my 3D flying brother in law wince and my buddy with a china box on his wag his head. As all here know. I don't do chi- na bling on glow motors. Hmmm. Think he is on his third hunnerd dollar trinket failure. And can't fly half the time cause his ignition battery has failed it was not charged. His R3 would run fine without it to. To each his own.
I would toss em in the trash if it took that to make them run. Jusayin
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FlyerInOKC

My Feedback: (6)

Its a possibility!

I will probably never own a multi cylinder Saito but I still enjoy reading about the group diagnosis of the 3 cylinder radial.

Glowgeek

Congrats! Here's how mine runs on 15% nitro.

FA115
16x8 (7830) 1.812 HP
17x6 (8170) 1.968 HP
15x8 (8680) 1.907 HP
16x6 (8700) 1.864 HP
14x8 (9800) 2.083 HP
15X6 (9850) 2.090 HP

acdii

With all my playing catch up on my vehicle and house projects I have yet had a chance to run up my 120R3 in the Corsair. I have my trailer pulled out of the barn, but has not yet made it to my driveway so I can charge all the planes and prep them for the field. Too many projects, too little time.

FlyerInOKC

My Feedback: (6)

Thank you for the numbers! The first thing I want to do is measure the engine and determine what size it actually is. The prop shaft thread size should be a good indicator to start with. Capt I sent you a PM this morning.

Captcrunch44

I will have to try and post vid of my 200r3.

Glowgeek

Prop shaft 8mm, Bore 31.7mm, Stroke 24mm, Displacement 18.94cc. "FA-115" will be cast into the muffler tail piece if its the original. If it's anything but an FA-115 I'd be very surprised. Even though they are still available new for big bucks it's pretty rare to find a good used one, especially at that price. Best of luck to you Mike.

FlyerInOKC

My Feedback: (6)

Now that I bought it I am wondering what I'll do with it. Impulse buy! I already told Mike, aka Captaincrunch44, I would let him know if I decide to sell it, he tried to buy it too. If he passes I'll open it to you guys first. I will check the prop nut size first and report back what I find. The engine looks awful big in the pictures to be a .65 but what I don't know about Saitos could fill books heck probably a whole library.

RoKit

Does your 200R3 have a modified intake manifold ?
Not many people seem to have a radial ,,
How does it run ,, are you happy with it ?

I am looking for pictures of a modified manifold,
If you have any could you please post..
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Captcrunch44

don’t worry I don’t like to pass up a Saito

Captcrunch44

runs good but never had it a part.

Hyjinx

Hey RoKitYou may find images on the other forums dedicated to the R3. There are history, allegations and solutions in detail on this love em or hate em Saito series.
Pretty fascinating stuff!
Probably wouldn't be out there if Carthuga hadn't bought a used one and had a problem.
Google search any key words.

acdii

You going to be at the fly in in September? Any RV campgrounds near there?

RoKit

Thanks... I am reading and reading..... have spent many many hours the last 2-3 weeks looking for information.
I am stubborn and will not give up yet.

Hyjinx

it's out there! There are chunks of gold in the internet sewer. Good luck and post your gains eh...love to learn.

Captcrunch44

yes a nice one just before you get to Montezuma
I believe it’s called Diamond lake

RoKit

Thank you for sharing your experiences. :-)
I think from a general perspective that our fuel systems are as simple as they possibly can be.
However there is grades of acceptable performance and if a "normal" application, let´s say an airplane of 4-5kg are using
20 meters of the runway waiting for the engine to clear out one of the cylinders, that would not be acceptable for me.
Or if you need instant power in a "go around" situation you would want to know that the engine is reliable enough to help you.
I know from what people have stated that there is plenty of engines that never had any mods and the owners are happy with them.

For me all the available information is somewhat confusing and I am trying to understand what the difference might be between a good and a bad engine ?
I refuse to pay two times for my engine just because Saito don´t take their responsibility toward its customers.
So consequently I am looking for a DIY manifold solution.

If I don´t manage,, the engine will end up in the "corner of shame" in my garage.

1200SportsterRider

In my opinion these R-3 Saitos need three things, toss all temperature measuring devices over the fence, peak the high speed needle, then set the low speed needle to optimum and you won't have a problem of any kind. No glow assist or ignition system needed.

My 120 R-3 at 6,000 rpm.

RoKit

That is exactly what I did and it runs fantastic at 1700 idle and 9200 wot with 16x8 MAS.
BUT
I also like to use the mid range,, my transition and mid range is very very much less than fantastic.

1200SportsterRider

The 120 R-3 pictured turned a Graupner 14 x 7 at 7,760 rpm and idled at 1,830 rpm with a very clean crisp midrange. The Keleo ring made zero tank pressure, it had no pressure tap when it arrived, I drilled and tapped it for a pressure tap, I attached a balloon and the balloon hung there mostly limp. The 170 might make some pressure.

Hyjinx

Ditto. If that's still a thing. My 450 lost a glow plug in the air Monday and still ran well enough to land without dead sticking. Lol Could have done a " go around" if needed.
Swapped the set to the HH plug they used to ship on the Evo radials. Ran fine but there was a slight hesitation as it entered " mid range" . It runs very well in midrange and that's pretty much where I fly it. It's overpowering my 24 pound airframe. But I like the just off idle sound as it goes by low and slow.
I think expectations play a large roll. It amazes me that with as much negativity about these types they still retain high value in the used market.
Bet the break room chatter is vibrant at the Saito plant on this subject.

acdii

Funny, thats what she said the other night. On my Corsair I put OBG so that I didn't need to set up a special harness and battery pack just for the one plane. It gives the plane a cleaner look too. It shares the landing gear battery.

the Wasp

My Feedback: (1)

oh yeah I found it, I found it, around town.

I found it, I called the AMA and they did not even know about it.

guys, go to page 18 of the June AMA Aviation mag, tell me if you find it.

I got a kick out of it, it's a crazy mistake. how could a manufacture make such a mistake, I even found it on Google Images (Google Images is your friend).
the AMA lady I talked to said they didn't know about this mistake and that she is going to Email the person that wrote the article and ask him about it. and she also told me that the last page (127) has a photo of the wrong Heli, she got a call yesterday about that photo.

let me know if you find it. I can see you all now looking for it LOL

Jim
PS, don't forget what John Wayne said, "I have more Saito's than guns".