Saito's New Engine: FG-90R3
#177
Join Date: Nov 2014
Location: Southern Minnesota USA
Posts: 225
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hi farmer, i have this engine in my TF giant corsair arf and am just loving it. i use the standard long threaded tool that is supplied with the engine and for me is a real trick to lite this engine up by flip starting it. when i choke the engine i have throttle closed not set @ idle but closed with the throttle cut off switch. i pull out on the choke tool and slowly turn the prop through 6-7 times of felt compression not 6-7 revolutions . then i open throttle to 1/2 and with just a few flips she will come to life @ about 3500rpm so be ready and make sure the model is held and anchored well !. even if i do this perfectly it dosn't always work that well when the engine is warm and i have tried not choking it at all after it has been started and still no start. so i bought a electric starter off ebay from china for 70 bucks ,run it on a 2200 3s lipo and she pops off much easier than flip,flip,flip,flip.
this is the starter that i bought .TOC Roto Terminator Starter for 20-80cc Engine, rc airplane D52*H30mm . i am really surprised the power/torque that this thing has on a 3s battery.
this is the starter that i bought .TOC Roto Terminator Starter for 20-80cc Engine, rc airplane D52*H30mm . i am really surprised the power/torque that this thing has on a 3s battery.
#179
#180
I have a second 90 so I have it all broke in with 2.5 gallons put through it on the ground at 3k with the adjustments out as fare as they would go just like it did for the one I am flying in my FW190. But now I am about the experiment. I got a walbro carb from mini motors in the uk. yesterday I ran it on the ground and it did fine. I only got 5600 out of it on the ground with a 24x10 prop and that was where it wasn't over lean it don't mind motors a little rich. I'm not done with this experiment yet.
#183
I hve the mini motor carb on mu fg 60r3 and it is still on the test stand. to start i just open the throttlle squirt some fuel in the carb. then i grab the prop and turn her thru, feel the little "bump" and she'll fire off in just one or two flips.... almost everytime
#184
My Feedback: (3)
From a storage or dry carb condition I use the starter and turn the 84 for 3-5 seconds with the ignition off to prime it. Then I turn on the ignition and use the starter and it fires up at idle speed very quickly. I've not had to use the stock choke this way. Then once the engine has been flown during that day it will flip start almost immediately for me.
I lije the Walbro carb mod idea too but so far it's running fine. I'm getting over 7000rpm in flight on a Xoar 24x14 wood prop currently so I'm going to switch to 24x10 x 3 blade to slow it down a bit.
This 84 is in a TF Corsair by the way, just though I'd mention how easy it is to start.
I lije the Walbro carb mod idea too but so far it's running fine. I'm getting over 7000rpm in flight on a Xoar 24x14 wood prop currently so I'm going to switch to 24x10 x 3 blade to slow it down a bit.
This 84 is in a TF Corsair by the way, just though I'd mention how easy it is to start.
#188
I have engine in the Hanger 9 Corsair. After my initial problem with it it now seems to run fine.
I have telemetry on it and it is turning about 6,000 rpms with a 24/10 prop.
I do have keleo ring but no smoke and am using the exhaust pressure.
I have about 2 gallons through it, and it starts right up using a starter after 10 flips or so choked.
On my second flight the engine ran good but every so often it would miss. Here is a video where you can hear it.
I had the idle a bit to low and it died on my landing approach. Hit hard enough to jam the gear through the top of the wing,
Got that repaired and on the third flight the engine preformed good but still had that miss from time to time.
Also noted that on a steep climb out the engine missed enough I did not do that again.
I need to figure out how to hold it nose up on the ground, Yikes.
Few questions.
What might be the cause of the misses?
Are you using the exhaust pressure?
My throttle response is all in the bottom half of the curve, hardly any rpm increase from half to full?
What kind of temps should it be running at?
Thanks in advance!
Kevin
I have telemetry on it and it is turning about 6,000 rpms with a 24/10 prop.
I do have keleo ring but no smoke and am using the exhaust pressure.
I have about 2 gallons through it, and it starts right up using a starter after 10 flips or so choked.
On my second flight the engine ran good but every so often it would miss. Here is a video where you can hear it.
Got that repaired and on the third flight the engine preformed good but still had that miss from time to time.
Also noted that on a steep climb out the engine missed enough I did not do that again.
I need to figure out how to hold it nose up on the ground, Yikes.
Few questions.
What might be the cause of the misses?
Are you using the exhaust pressure?
My throttle response is all in the bottom half of the curve, hardly any rpm increase from half to full?
What kind of temps should it be running at?
Thanks in advance!
Kevin
#190
I am using a 6.6 volt life battery from Electrodynamics. The manual indicates 6 to 12 volts so figured it would be OK.
I have no idea how the ignition module works. Does it regulate the voltage down to a certain voltage or pass through what ever is coming in.
I can change to a Lipo easy enough.
I have no idea how the ignition module works. Does it regulate the voltage down to a certain voltage or pass through what ever is coming in.
I can change to a Lipo easy enough.
#191
My Feedback: (8)
I am using a 6.6 volt life battery from Electrodynamics. The manual indicates 6 to 12 volts so figured it would be OK.
I have no idea how the ignition module works. Does it regulate the voltage down to a certain voltage or pass through what ever is coming in.
I can change to a Lipo easy enough.
I have no idea how the ignition module works. Does it regulate the voltage down to a certain voltage or pass through what ever is coming in.
I can change to a Lipo easy enough.
#197
My Feedback: (3)
Just run it and tune it as you get to know the engine. The stock 84 also did the same thing as you described with the stumble or miss and it concerned me too. I flew two different Corsairs with 84's and Keleo rings and both concerned me for the same reason. We sent one to be modified, the intake manifold is this engines weakness. After the mods telemetry reads 7400rpm in flight with a 24x14 Xoar prop. It pulls the TF Corsair around like nothing's there and runs clean and consistent.
The newer engine is supposed to be a development of the Ray English mod for the 84. You should be able to tune that stumble out. Use Klotz oil and Non-Ethanol 92 gas. Watch those peak rpm's too. Temps should be even between all cylinders and watch that they are under 200F. Mine runs around 175F on a typical day.
The newer engine is supposed to be a development of the Ray English mod for the 84. You should be able to tune that stumble out. Use Klotz oil and Non-Ethanol 92 gas. Watch those peak rpm's too. Temps should be even between all cylinders and watch that they are under 200F. Mine runs around 175F on a typical day.
#198
Join Date: Nov 2014
Location: Southern Minnesota USA
Posts: 225
Likes: 0
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2 Posts
From a storage or dry carb condition I use the starter and turn the 84 for 3-5 seconds with the ignition off to prime it. Then I turn on the ignition and use the starter and it fires up at idle speed very quickly. I've not had to use the stock choke this way. Then once the engine has been flown during that day it will flip start almost immediately for me.
I lije the Walbro carb mod idea too but so far it's running fine. I'm getting over 7000rpm in flight on a Xoar 24x14 wood prop currently so I'm going to switch to 24x10 x 3 blade to slow it down a bit.
This 84 is in a TF Corsair by the way, just though I'd mention how easy it is to start.
I lije the Walbro carb mod idea too but so far it's running fine. I'm getting over 7000rpm in flight on a Xoar 24x14 wood prop currently so I'm going to switch to 24x10 x 3 blade to slow it down a bit.
This 84 is in a TF Corsair by the way, just though I'd mention how easy it is to start.
how did the 24x10 3 blade work out ? mine is just screaming with the 24x12 and i sure do not want to grenade this FG90.
#199
My Feedback: (3)
I still need to get the Solo hub for my blades. I have 4 matching scale 24 inch blades I plan to use. I'll set the pitch to a max RPM at full power to keep it inside the safe range.
I don't recommend a thin prop blade on these engines. From past experience the thin blade props like Mejzlik allow the engine to over rev. I use Xoar most of the time but there isn't a prop for this requirement.
I don't recommend a thin prop blade on these engines. From past experience the thin blade props like Mejzlik allow the engine to over rev. I use Xoar most of the time but there isn't a prop for this requirement.
#200
Hey Chris and other Saito masters,
Trying to tune a FG 84. Starting with 3 turns on the High and 5 turns on the Low. Low end needle is responsive but getting no response with the main needle. Tried turning in a full turn...and out a full turn...no response. Tach is reading 5600.
Any ideas why the main is not responsive?
Thanks,
jim
Trying to tune a FG 84. Starting with 3 turns on the High and 5 turns on the Low. Low end needle is responsive but getting no response with the main needle. Tried turning in a full turn...and out a full turn...no response. Tach is reading 5600.
Any ideas why the main is not responsive?
Thanks,
jim
Last edited by jimkron; 09-30-2017 at 08:12 AM.