jws_aces

My Feedback: (33)

Kevin

First off congrats on the flight. What prop? 24x10 or 24x12? I flew mine again this past weekend at Sod-buster war-bird flyin. It was very hot. I flew for over 10 mins on each flight. Now remember I am on my 5th gallon of fuel so it is broke in. I have not adjusted the needles at all since I broke it in. I flew for a couple guys that have 84cc and 90cc some Ray Mods also. We check the in-flight RPM on the zoar 24x12 we saw 7800 in a dive and 7200 most of the other times. It gets the prop sound like yours did.

Love the sound and the Corsair. Keep it rich. Mine does the exact same thing on take off but by the time I reach the first base leg she is screaming with no issues.

cordline

Hi kevin,

Great you got your maiden on the Corsair.
If your engine sags at full throttle you are still too lean at the top end and may damage your engine.
I don't think it is good practice on these radials to set them at max rpm then just back off 1/8 turn, the top cylinder will be too lean.
Richen the top end until you have an acceptable CHT on #1 cylinder (all Radials, full size included,run hotter on the top cylinder) and there is no sag between 3/4 and max throttle.

cordline

Oh and as Jeff points out, run on a 24x12 so it does not over rev in the air

radfordc

My Feedback: (14)

Saito recommends setting the low speed needle as lean as possible while still having good acceleration from idle to full speed; and the high speed needle as rich as possible while still having adequate power for flight.

jws_aces

My Feedback: (33)

The only issue I had with that is when I was setting mine up with a infrared thermometer I had to richen the low needle because if I didn't the highest temps were at mid throttle. It would cool down when I move the throttle past half way. I even tell myself when flying not to stay at mid throttle to long. I tried once to lean mine out just 1/4 of a turn and it wouldn't start. Remember I have a no modified intake.

ForcesR

Saito gas engine carburetors are very sensitive when it comes to fine tuning the low and high speed needles. Needle movements should be done in minutes, not in 1/8 or 1/4 turns etc. I learnt this from tuning my FG20 and FG36; needle movements in minutes is the way to go for fine tuning a gas Saito. The maximum I ever turn the LSN or HSN for a leaner or richer setting is two minutes maximum at a time. It may be frustrating and time consuming using the minute movement technique but in the end you will have an engine that runs and accelerates the way a well tuned Saito engine should. My FG90 and FG60 will be fine tuned the same way as my FG20 and FG36.

kevarc

My Feedback: (2)

Thanks All!
I am using a 24x12 Xoar prop.
I did check the CHT at full throttle and all were running 175-185. I have no idea if that ok or not but did not seem too hot.
I did not check them at mid throttle.
I was worried about getting it too lean but maybe I can go a little more.
Also I would like to set up the telemetry to monitor the engine. Can I use the tack lead from the ignition box or do I need a different pick up?
I am using a Spektrum Radio.
Thanks
Kevin

jws_aces

My Feedback: (33)

Temps sound great at full throttle. Just make sure that if it's under a cowl that the air flow exits are equal all the way around the back if not then you must Baffle it.
Post video once you fly it.

jagdpanther9

hi guys,great thread. i just broke on my FG90 with no issues. i was a bit nervous about it after seeing the damaged rod and other issues but all turned out well. i added a good oz. of KL-200 to the crank case vent and worked it in by rotating the prop and turning the engine every direction.i mixed the KL-200 @ 15-1 with non ethanol 91 gasoline. i had to choke the crap out of it to get it to fire but it did start by flip starting it. 5 turns out on the slow speed and 12 turns out is where the main ended up after the first 1/2 tank. it was so rich that 2 cylinders were missing but that is what they wanted. i then went to 8 turns out on the main and ran the rest of the brake in fuel . mine ran @ 160 deg for cyl. 1 140 for cyl. 2 and 139 for cyl. 3 using a 24x10 prop. i am pretty relieved @ this point and will be tuning with a xoar 24x12 .

All good so far.

jagdpanther9

hi guys, i am still testing and tuning my FG90 .i reset the valves per the manual and found that just one was within tolerance. so far i have fouled 1 plug on # 3 from running the engine too rich . i gave the engine a new set of plugs. i set the gap @ 5.5mm and still was having trouble with #3 being too rich and cutting in and out in lower rpm. i was running a 2 cell 2500mah life battery for the ignition and then switched to a 2 cell 7.4V lipo and this made a big difference in how the engine runs. i gained 200 rpm on the top just from going to the lipo. i am making very short pulls with a 24x12 xoar and getting right @ 6000 rpm. the temps are 140 on # 1 120 on #2 and 120 on # 3 but # 3 still drops off @ idle . am i still too rich or is # 3 a problem child in these engines. slow needle is 4 3/4 main is 5 3/4. by the manual it is very rich but if it wasnt for #3 droping off @ idle i would be happy with it. i have 1 gallon of fuel through this engine now. i have also read about guys tilting the engine to put #3 or #2 to the top for break in.

any comments or suggestions would be great. =D

tfarmer96

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tfarmer96

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cordline

I found this on another thread.
During the Run in process rotate the engine on the stand so that each cylinder has a turn at the top.
This prevents the #2 and #3 cylinders getting lazy and not running in.
I did this to my FG84 and all three cylinder have a very similar compression and run at close temps.
Perhaps may work for you.

cheers

Wayne

jagdpanther9

hi wayne, my problem ended up being that it was 40 degrees outside and the engine couldnt warm up enough with such a rich mixture. now that it is spring/summer it runs perfect. my TF corsair is coming along nicely and i should be on to mounting the engine soon. i have my fiberglass specialties cowl and cooling baffles from keleo as well. there is just one problem, i really want another one just to keep on the test stand and play with in the shop!! i REALLY like this engine =D.

aaac

Hello, sorry to bring this subject here but i am from Brasil, and here we dont have any assistance to saito engines, need some help, I have a saito engine FG-36 about 3 years ago and always worked well, although internationally faulty reputation (not all), the running in was without problems and regulated easy (never had to do more then some clics on the needles). I have always used ordinary gasoline (washed with distilled water because here all brands of gas come with 30% ethilic alcohool) and Motul 800 oil. The problem arose last week, I start it normally but did not want to give more than 5900rpm with an 18x8 prop that normally turned at 7800... regulate low here, regulate high there ... I lost parameter and had to return the factory settings, which was not working anymore. The idle worked as a clock, but no power in full throttle at all. It turned out that the worst was yet to come, the high setting was getting worse and worse and it became very hot and it began to die due to high temperature. I took out the cowl and made no difference, even same symptom. I tried to rich the mix, but the overheating was getting worse with the attempts and it started not to start anymore when hot. Today, it does not work for 1 minute in idle before overheat and die. It also appears that the oil excess from the rear cover is going out in its original color, as if it had not been passed through the engine (before it had spilled in more darkened color) and the engine is not spitting at the exhaust any Carbonized oil sludge. The engine has rarely been used in this 3 years and should be about 10 hours running time. Please help me!!!! I do not want to have to open this saito gasser in my amateur bench... My doubts are, if anyone knows: 1- Can synthetic 2 stroke oil clog somehow the lubrication lines and / or form some internal film that is causing this lack of engine lubrication and overheating? 2- What internal part would have to break in this engine so the engine keeps turning on and running normal idle and at the same time overheating so fast. 3 - Excess oil in the mixture with the gasoline overheats the engine? Because I wanted to try for more oil than recommended to see if it "unlocks" or it will only get worse. One thing is certain, has something clogged and warming up the engine... mechanical part, old oil clog ?????

n8622t

My Feedback: (8)

I have read that ethanol is is hard on rubber products and can also cause carburetor issues by leaving sediment ... you might start with the carb by disassembling inspect and clean. Also, add Seafoam to your fuel. It's a fuel additive that moki owners use which cleans fuel pathways and internal engine parts as well as lubricant, just add it to you normal fuel/oil mix.
Hope this helps
jimmy

ForcesR

aaac; you mentioned that with 10hrs of run time you have only had to do LSN & HSN adjustment. I have the FG36, a 2009 model and it runs very, very well. Have you ever checked the valve/tappet gap since owning the FG36? If the valve/tappet gap is to large you will not be able to achieve maximum RPM and overheating of the engine may occur. Check the valve/tappet gap, adjust as required in accordance with engine manual instructions..

Roger

SWORDSN

My Feedback: (13)

deleted

SJN

My FG 84 still going strong last weekend :-)

DanIsGo

what is the weight and wingspan of your yak? It is a great looking plane and cruises by very nicely with that engine. I am considering putting the 90 in my ziroli hellcat 95inch wingspan and I want to make sure it will be enough. Thanks

SJN

It 96" span , and 38.5lbs

The CY model Yak 3U/Yak-11
Cheng Yang Model Factory

Vertical performance is not great at this weight, but it flys very scale.
Needed loads of lead in the nose to get the CG :-)

vatechguy3

My Feedback: (11)

Any updates from summer use??

tony

tfarmer96

Heres mine.

HARRIS-G

All Saito radial come from the factory dead dry and need to put through the breathing niple 10-15ml oil before the first run. Pay attention to valve clearance, most of the time they need to be adjusted before the first run...... And finally if you can build a rotating stand to bring all the cylinders in up position so all of them warm and cool down the same running time. After that on your plane you MUST buffle the engine to run as cool as posible, and use at least 95octane gasoline due to high compression of the engine to avoid detonation...

Good luck

(Here is a short video of mine rotating stand...)

jagdpanther9

my top flite giant corsair ARF is one mean hot rod with this FG90! this video will give you an idea of how the FG90 will fly the TF corsair. i did run a gallon of fuel through my engine on the test stand. mine did not rotate but it seems to run just fine. i did squirt a good ounce of klotz in the breather hole and turned the engine in all directions while rotating the prop to make sure it covered everything internally. i did preform a valve adjustment after about 1/2 gallon and indeed there was excessive clearance. my mixture needles ended up @ about 6 turns out on the high speed and 4 1/4 or so for the low speed. it was nearly 90 degrees when i this video was made.mine is very finiky on flip starting it. i use the goofy stock choke set up and pull out on the choke wrench thingage and pass the prop through 3-5 complete revolutions. usually it is flooded and wakes up blaring about 1/2 throttle after 15 or so flips. it fires right off with an electric starter.i am running the xoar 24x12 prop. hands down this is the most exciting coolest sounding most fun model i have ever built!!!! i really look forward to the next time out.