Saito's New Engine: FG-90R3
#253
My Feedback: (38)
Question.
since the 90 and 84 are somewhat similar, I am having some problem with my stock 84.
All was running good, great idle good transition and good full throttle.
i had a rough landing and now for whatever reason, idle is great, full throttle is great but in the middle now it hesitates sounds like he’s running to rich.
How could it have changed from just a rough landing?
any idea how to smooth the middle power band?
If I send it to horizon do they run it and tune it for you?
thanks for the help.
since the 90 and 84 are somewhat similar, I am having some problem with my stock 84.
All was running good, great idle good transition and good full throttle.
i had a rough landing and now for whatever reason, idle is great, full throttle is great but in the middle now it hesitates sounds like he’s running to rich.
How could it have changed from just a rough landing?
any idea how to smooth the middle power band?
If I send it to horizon do they run it and tune it for you?
thanks for the help.
#254
Join Date: Nov 2014
Location: Southern Minnesota USA
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This is the most I've spent on an engine ever but couldn't help myself after watching the engines perform at Wenatchee NW Scale championships. I haven't run it in yet but am concerned that the person in this thread disassembled his new engine to discover a lack of oiling from factory. How does one get oil into the crankcase to lubricate all parts before startup?
#255
Join Date: Nov 2004
Location: Altillac, France
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Hi everyone, will somebody please tell me the inside diameter of the Keleo ring exhaust for a FG-90 R3.
The inside diameter of the ring not the tube that the ring is made from.
Thank you in advance
The inside diameter of the ring not the tube that the ring is made from.
Thank you in advance
#256
Inner Diameter: 6.8125.
Last edited by ForcesR; 10-27-2018 at 05:04 PM.
#258
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Join Date: May 2002
Location: Yoncalla, OR
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Catastrophic failure??
I keep hearing about some owners of this most popular engine who have been experiencing catastrophic failure in flight.. I know it's a subject a bit negative, but I would like to explore any common reason that would consistently cause this very expensive problem and possibly avoid it?
#260
Join Date: Nov 2014
Location: Southern Minnesota USA
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use the recommended oil , brake the engine in on a test stand not in the air with at least 1 gallon of fuel keeping the mixture rich.use at least a 24x12 prop to keep the rpm down. and like sonnich said keep the engine cool using baffling in your cowl . also on mine i have made 2 valve adjustments in the last 3-4 gallons of fuel. if you look back a few pages in this thread there is some good info on break in and tuning. by far this has been my favorite engine so far.
#261
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Join Date: May 2002
Location: Yoncalla, OR
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use the recommended oil , brake the engine in on a test stand not in the air with at least 1 gallon of fuel keeping the mixture rich.use at least a 24x12 prop to keep the rpm down. and like sonnich said keep the engine cool using baffling in your cowl . also on mine i have made 2 valve adjustments in the last 3-4 gallons of fuel. if you look back a few pages in this thread there is some good info on break in and tuning. by far this has been my favorite engine so far.
#262
Join Date: Nov 2014
Location: Southern Minnesota USA
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i know of one for sure that the guy treated it like a 55cc two stroke and said "i will just brake it in flying it" . his grenaded. i saw a guy flying an FG90 in a ARF zero lean as heck hot as hells blazes and he got away with it. it was suggested that he fatten it up which he did and he went on his merry way for the rest of the event. really i dont think that you hear all of the success stories from all of the folks out there who are happy as clams flying the heck out of them. but when things go haywire people love to vent. the sayin goes something like " it takes 1 oh crap to screw up 100 at a boys"
i am very pleased with mine flying it hard in my TF corsair with a big grin on my face. what i heard made me nervous too but i just made sure to brake it in good and i am very pleased.
i am very pleased with mine flying it hard in my TF corsair with a big grin on my face. what i heard made me nervous too but i just made sure to brake it in good and i am very pleased.
#263
Mine's prepped for the break in. Well oiled up, all valves checked (only one out of tolerance), instrumentation installed. At least 1lt vertical to make sure all cylinders heat up.
8
8
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jeep36 (02-26-2021)
#264
Question.
since the 90 and 84 are somewhat similar, I am having some problem with my stock 84.
All was running good, great idle good transition and good full throttle.
i had a rough landing and now for whatever reason, idle is great, full throttle is great but in the middle now it hesitates sounds like he’s running to rich.
How could it have changed from just a rough landing?
any idea how to smooth the middle power band?
If I send it to horizon do they run it and tune it for you?
thanks for the help.
since the 90 and 84 are somewhat similar, I am having some problem with my stock 84.
All was running good, great idle good transition and good full throttle.
i had a rough landing and now for whatever reason, idle is great, full throttle is great but in the middle now it hesitates sounds like he’s running to rich.
How could it have changed from just a rough landing?
any idea how to smooth the middle power band?
If I send it to horizon do they run it and tune it for you?
thanks for the help.
Just a thought,
jim
#266
#267
Thanks Jagdpanther.
Dan, yes the FW190 lives on. The 90 will go to a GeeBee. Being a little bit wiser this time, I am going to try netralising gravity for the over-rich initial runs to get all jugs running at the same time. Will report how that went.
Dan, yes the FW190 lives on. The 90 will go to a GeeBee. Being a little bit wiser this time, I am going to try netralising gravity for the over-rich initial runs to get all jugs running at the same time. Will report how that went.
Last edited by hpergm; 12-25-2018 at 04:04 PM.
#268
My Feedback: (9)
Scale warbirds - TopRCModel SCALE WARBIRDS,JET, PATTERN, BOATS & MULTIROTOR
#270
Join Date: Nov 2014
Location: Southern Minnesota USA
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i really enjoyed braking in this engine but it was time consuming . i have to agree that these engines are very efficient and for the enjoyment of the performance and sound and efficiency they are worth every penny. at some point i would like to try out the FG-19R3 in a 55"-60" span model.
#271
First run today at the mountain (keeps the neighbours happy). Was able to hand start it (!).
Went through 1.5lt of 1:15 fuel. RPM was kept below 4k. Music (ring muffler) by Meier.
Instrumentation worked flawlessly and allowed me to control the heat balance/cycle of all cylinders by setting the Low needle leaner (but still rich) than the High and then making throttle adjustments*.
*There is a some theory behind this, but the logic loop goes like:
A. Rich carb settings = floods cold inlet chamber = "top" cylinder is usually leaner. In this video, Cylinder #1 is lower than #2 and #3 due to the stand inclination, so ehxibits the lower temps (basically, cold). Go to B.
B. One/two cylinder(s) firing = high gas pressure = increases burnt gasses blow-by = extinguishes opposite (2nd/3rd) rich cylinder (due to reverse blow-by, as piston rings are not yet seated). Go to C.
C. Reduce throttle a little = lower rpm = less frequent blow-by of firing cylinder = higher chance for opposite cylinder(s) to relight (Low needle is leaner than High). Wait until D.
D. Cold cylinder(s) relight = allow reaching of operating temp. Go to E.
E. Increase throttle a little to increase all firing temps (more frequent explosions) = high gas pressures = increases burnt gasses blow-by = extinguishes opposite cylinders or the temp of the firing cylinder(s) climb above 165C. Go to C.
Due to the volume of the inlet chamber and the hysterisis of the temp recordings, this feedback cycle takes more than 2-3 mins.
During that time, one can see the cylinders dropping and popping back up at random.
Break in is complete when:
(i) Between 1/3 and 2/3rds throttle no cylinder drops (i.e. B does not happen = all piston rings are seated properly, no reverse blow by).
(ii) Cylinder temps are within 5C of each other and less than 165C max (following the leaner carb setting possible to achieve this result).
Went through 1.5lt of 1:15 fuel. RPM was kept below 4k. Music (ring muffler) by Meier.
Instrumentation worked flawlessly and allowed me to control the heat balance/cycle of all cylinders by setting the Low needle leaner (but still rich) than the High and then making throttle adjustments*.
*There is a some theory behind this, but the logic loop goes like:
A. Rich carb settings = floods cold inlet chamber = "top" cylinder is usually leaner. In this video, Cylinder #1 is lower than #2 and #3 due to the stand inclination, so ehxibits the lower temps (basically, cold). Go to B.
B. One/two cylinder(s) firing = high gas pressure = increases burnt gasses blow-by = extinguishes opposite (2nd/3rd) rich cylinder (due to reverse blow-by, as piston rings are not yet seated). Go to C.
C. Reduce throttle a little = lower rpm = less frequent blow-by of firing cylinder = higher chance for opposite cylinder(s) to relight (Low needle is leaner than High). Wait until D.
D. Cold cylinder(s) relight = allow reaching of operating temp. Go to E.
E. Increase throttle a little to increase all firing temps (more frequent explosions) = high gas pressures = increases burnt gasses blow-by = extinguishes opposite cylinders or the temp of the firing cylinder(s) climb above 165C. Go to C.
Due to the volume of the inlet chamber and the hysterisis of the temp recordings, this feedback cycle takes more than 2-3 mins.
During that time, one can see the cylinders dropping and popping back up at random.
Break in is complete when:
(i) Between 1/3 and 2/3rds throttle no cylinder drops (i.e. B does not happen = all piston rings are seated properly, no reverse blow by).
(ii) Cylinder temps are within 5C of each other and less than 165C max (following the leaner carb setting possible to achieve this result).
Last edited by hpergm; 12-26-2018 at 02:24 AM.
#272
Break in progressing well; all cylinders are heat cycling and balancing EGTs well at certain throttle settings...
Mixtures are still set very rich. Max rpm does not go above 5.5k rpm - there is still some time to go until 6k is possible.
At this point the engine has consumed about 4lt of 15:1 fuel.
Mixtures are still set very rich. Max rpm does not go above 5.5k rpm - there is still some time to go until 6k is possible.
At this point the engine has consumed about 4lt of 15:1 fuel.
Last edited by hpergm; 01-06-2019 at 07:57 AM.
#273
Join Date: Nov 2004
Location: Altillac, France
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Hi everyone,
Due to health reasons, I am thinking about buying a hand held electric starter for my FG-90 R3, do any of you guys use a starter ? If so, which one ? I would appreciate some comment from somebody who actually uses one.
Thanks in advance
Andrew
Due to health reasons, I am thinking about buying a hand held electric starter for my FG-90 R3, do any of you guys use a starter ? If so, which one ? I would appreciate some comment from somebody who actually uses one.
Thanks in advance
Andrew
#275
Join Date: Nov 2004
Location: Altillac, France
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Thank you for that liemtran75 .............. unfortunately I have just been told by Sullivan that Miller RC products no longer exist, the factory was destroyed in the recent fires in California.
Any other offerings would be apreciated ............ especially if someone is using a Sullivan S651 Starter .......... is it powerful enough to start a Saito FG-90 R3 ?
Thanks in advance
Andrew
Any other offerings would be apreciated ............ especially if someone is using a Sullivan S651 Starter .......... is it powerful enough to start a Saito FG-90 R3 ?
Thanks in advance
Andrew