treasure

I have a Saito 170 mounted in a Great Planes Super Stearman.
I have run a gallon plus of fuel through it. It is installed with an Electrodynamics on board glow setup.
I am having a problem with one cylinder not always lighting up on throttle up.
I almost lost the airplane due to this.
This is my first experience with a radial and onboard glow setup.
I have the onboard glow setup to turn off about half throttle.
I am running Powermaster 15% Castor/Synthetic blend.
Does anyone have any suggestions and/or experience with this engine?
Thanks
Bill

Hobbsy

My Feedback: (102)

Does it lose this cylinder while the glow lighter is on, if so the low speed needle could be a little lean. I can't imagine it losing a cylinder with the glow lighter on if it is a little rich.

treasure

I think it looses the cylinder during acceleration at the transition from on to off.
Thanks
Bill

Hughes500E

My Feedback: (16)

You must run OS F Plugs

Also, you should set your onboard glow to a switch and not the throttle stick. If you lose a cylinder you don't want to pull the stick back to re-light. A sudden drop in altitude is scary!

It is a common problem to lose the 8/7 oclock cylinder but not at half throttle, only on approcah or idling etc. Run F plugs and set your intake valve clearance "tight" on that cylinder, this will allow for maximum fuel entering that cylinder! 1 gallon is still break in! I bet your valve has "loosened up" during the initial runs thus increasing the clearance allowing even less fuel to enter plus poor plugs or if you are using F Plugs, a lean needle or both.

Hobbsy

My Feedback: (102)

The OS Fs will do nothing for it, I run the stock plugs in my .90 triple and Fox Miracles in my TS .90 and 4 Fox Miracles in my 1.30, they do not drop cylinders.

Hughes500E

My Feedback: (16)

Of course it will, the OS F plug is the best plug on the market for 4 strokes.
This has been proven many times over !

Hobbsy

My Feedback: (102)

By whom, I can take another brand plug out of any fourstroke I own, Enya, Saito, YS, Laser, Abitar, HiMax or Webra and there will be no change what so ever. I've proved that over and over. If any plug shows an improvement in idle and transition it is the GloDevil 4C Special.

treasure

I appreciate the input.
I will try the suggestions.
Thanks
Bill

Hughes500E

My Feedback: (16)

Bill what prop are you running? A larger diameter prop will also help with a flywheel effect. I am running an 18-6 on mine and idle can be as low as 1600 on 10%

Hope it works out for you.

Steve

wiz310

do you know which cylinder it is?. could be if its mounted in the Y shape, and a little rich, the plug could be flooding. if its in the inverted Y, it could be that the top cylinder is a little lean and cutting with a rapid throttle change.

bigphil

My Feedback: (6)

Seems like different plug suggestions may be cast in doubt by some but I'll still give you my experience any way.

I was breaking in my 170 radial this spring with the stock (McCoy) plugs and Sig 10% 4 stroke fuel. I had a terrible time with both bottom cylinders dropping out. We have another fellow in our club who had been running the 450 radial who had similar problems when he first started running his. He recommended to me the Saito plugs and Wildcat 15% synthetic fuel. I changed my plugs and fuel at the same time and it has run perfectly ever since. I can turn the glow off once it's started and let it idle for 5 minutes and it will still throttle back to full instantly. I have since run out of the 15% fuel and tried Omega 10% and was dropping a cylinder again in the air. I can relight it by throttling back but it, of course, makes me nervous.

I don't mean to hijack your thread but if somebody knows how to get them to run reliably on 10%, I'm interested. I usually run 10% in everything and haven't had problems with any other 4 strokes including other Saitos, OSs and Magnums. My radial has comparatively low time on it. Maybe an hour on the test stand and now 15 flights on the Stinson. I was convinced that 15% fuel was going to be a necessity.

blw

My Feedback: (3)

I just bought one and haven't made a test stand yet for it. I plan on running 15% Omega as I do in everything else.

Hughes500E- sorta interesting to find you over here in the 170R3 thread. I've been following your build on the CG Sukhoi 26 and am planning on putting my 170 in that. Any thoughts about doing this? I called CG and got the cowl measurements. It will fit. You already know what the engine weighs.... I plan to fly it doing scale aerobatics if it has enough power.

Wouldn't losing a cylinder on throttle up point to a lean condition as the first place to start if the valves are set okay?

Hobbsy- you probably know that I respect your opinions on engines. What do you think of the Saito SS plug?

WycheG

My Feedback: (4)

I would listen to Hobbsy on this one.

The Saito 3-cylinder engines are delivered with VERY rich low end settings.

I only run 10% nitro and my engines do not drop a cylinder (I have two 450's and I had fits with my first one dropping a cylinder in transition until I found the low speed needle and used it). It's all about the low end with these engines in my experience. Get the low end leaned properly and your fuel consumption will drop DRAMATICALLY also. I forgot how many full turns I had to lean my low end (it was a LOT and I was wondering if it was ever going to stop) but it was definately necessary. Many guys think a big multi will just drink the fuel -- and it will if your low speed is overly rich -- but set it up right and you'll be surprised how long you can fly on a tank of fuel.

Set up your engine correctly and you won't need new plugs (the thing is delivered with plugs that are up to the task) and you won't need a glow driver for anything but startup and you won't force your engine to devour more fuel than is necessary. Follow these procedures to set the low speed (number 3 in the link below) and let us know if your problems disappear.

http://www.saito-engines.info/throttle_setup.html

Leave the plugs alone, leave the nitro content alone, lean the low end (and don't be surprised if you are turning and turnng to get there), and please let us know how it comes out. I think you'll be plesantly surprised.

Happy flying.

Greg

Hobbsy

My Feedback: (102)

Barry, my 1.25 and .90 triple came with the new SS plugs, so far so good. It only took about 20 minutes to get the .90 to run and idle without glow power.

blw

My Feedback: (3)

So you and W8YE have 90s now? I found a NIB 30 Golden Knight when I bought the 170. The plugs in the 170 have no markings and mine must be one of the first ones sent here. It came with the manual for the twins, and had a crude set of instructions that look photocopied. It was a rush job for sure.

Hughes500E

My Feedback: (16)

Best sport plane I have built to date, I actually have a set of enlargened CG_SU26 plans with a cowl and canopy for the near future. Interesting fact, there was a CG SU-26 at my local field with a Saito 170 3cylinder. It was this plane that made me build the one in the thread your following. Another interesting fact, it was remembering that sound from that plane that made me buy this 170 LOL

It is a good combination, keep it light!


I have the scale bug now. I'm scratch building a 20% Waco YMF-3 [8D]
Going with a good smoke system simulating crop dusting at the 07 Scale Masters Qualifier next year here in BC.


PS
He sold his 170 (kept dropping a cylinder) to a guy I know, his is now running good now to

EDIT: guess I should set the date on my camera !

blw

My Feedback: (3)

Hughes500E,

Thanks a lot for all of the good information. It looks like the kit is light already. I've read where some reinforce here and there, and some say to build it by the plans.

I don't know about onboard glow yet. I'll see how it runs on the test stand first. Since they sound so good, I'll probably put a lot of fuel through it first for kicks. I definately want to have several hours on it to set the needle valves in the ball park before flying.

The Sukhoi is a plane that I didn't pay much attention to until recently. Now, I really like the lines and round cowl. It does grow on you!

scale dail

My Feedback: (8)

Those who have the Saito 170, what fuel do you use, ignition harness? exhaust? prop? I have in process an FR-1 Fireball with a 72'' span and about 17 pounds and the 170 should just about fit in the cowel.

blw

My Feedback: (3)

Hobbsy- My 1.25 ran fine on the first tank without the glow igniter. I didn't have it on for more than 30 seconds. It was vibrating a lot on the third tank but held 2700 RPM for 5 minutes.

Scale Dail- I plan to run Omega 15% with maybe more castor added. I have a 15x8 prop for break in. I'll use Saito SS plugs.

Hughes500E

My Feedback: (16)

I'm running 10% fuel with tight valves and an onboard glow on a switch, I'll probably switch to 15% when I run out of 10. I will only run OS F plugs for reliability, original owner had troubles with Stock Saito plugs

As for exhaust, I'm running 3 seperate silver soldered stacks exiting at a 45degree angle. This is a good exhaust as well
http://www.keleo-creations.com/Radial/saito170.htm

blw

My Feedback: (3)

If I have problems I'll switch to the OS 8s. Thanks for the info on your friend having problems.

Hughes500E

My Feedback: (16)

I don't recommend the 8's, it may be ok but the F-plugs are great.


I should also say that this engine was purchased new in 03. The stock Saito plugs may have changed since then, not sure!

blw

My Feedback: (3)

Yeah, I knew that. I was just testing you. F's then if the SS plugs don't work out.

I have no idea what plugs are in the engine now. It is one of the first ones made and didn't have a manual with it. It came with a crudely translated photocopy of instructions. It has been new in the box ever since the guy bought it. I got the engine for a fantastic price 2 months ago and got word the other day that he passed away last weekend. He was a nice guy with lots of flying stories. He did the best covering jobs that I've seen.

Temple

Hey Treasure--
How you coming with the 170 and the Super Stearman??? Post some pics if you can. Did you use the cowl to enclose the engine, or leave it off??? Would the 325 have been too large or too heavy on this plane??

treasure

Thanks for all the replies.
I have not run the engine since my post.
The weather here has cooled off and we have had a lot of rain.
I guess I am a wimp but I didn't feel like playing with an engine on my hands and knees in the cold.
I will try the suggestions in the spring and report back.
Temple if you email me [email protected] I will send you some pictures.
The 170 fit the cowl perfectly with no cutting. I am not sure if the larger engine would as the 170 was a pretty close fit.
Thanks again
Bill