Gas radial engines
#551
So the fix for the FG84R3 is in...
hpergm early on suggested that rather than taking the FG84R3 off the market and fixing it, Saito would make a different version with Ray's fixes and the 84 would disappear... looks like that will turn out to be correct. See his quote below, from the FG60R3 thread... I think he may have nailed it!
I also received the engine a few days ago. Destined to be installed in an 86" Top Flite FW190.
- Saito will probably never acknowledge the FG84's design shortcomings as this would entail warantee work on existing engines out there. I think they will just phase it out gradually.
- Instead, I see them releasing a "New!" FG75R3 in the future with 1.50 size cylinders (just to be different to the 84), same diameter and power-to-weight ratio as the FG60, but now able to swing an 23x10 @ mid 6,000s for a thrust of ~30-32lbs.
- Saito will probably never acknowledge the FG84's design shortcomings as this would entail warantee work on existing engines out there. I think they will just phase it out gradually.
- Instead, I see them releasing a "New!" FG75R3 in the future with 1.50 size cylinders (just to be different to the 84), same diameter and power-to-weight ratio as the FG60, but now able to swing an 23x10 @ mid 6,000s for a thrust of ~30-32lbs.
Last edited by slither; 08-01-2016 at 08:09 PM.
#552
I solved the problem with the ignition I adjusted the valves and the spark plug gap to 0.3mm, also checked everything ( i had missplaced an ignition cap to the wrong cylinder and also put a dedicated lipo for the ignition and I am having 7350 RPM max from a menz 18x6. This is with 6% nitro 6% oil and the rest methanol.
#553
My Feedback: (156)
Curious to see if the Ray's designs made there way into the new FG-90R3???
https://www.youtube.com/watch?v=c_9OM8eCGV4
#554
hpergm early on suggested that rather than taking the FG84R3 off the market and fixing it, Saito would make a different version with Ray's fixes and the 84 would disappear... looks like that will turn out to be correct. See his quote below, from the FG60R3 thread... I think he may have nailed it!
Great find this preview ad for the FG90, but I am still hoping for an FG75 with the 225mm size of the FG-60 to fit most 50cc warbirds but swing another inch on the prop. Looking at it from a positive perspective, the 90 now creates more "space" between itself and the 60 - hope dies last.
Hector.
#555
Senior Member
hpergm early on suggested that rather than taking the FG84R3 off the market and fixing it, Saito would make a different version with Ray's fixes and the 84 would disappear... looks like that will turn out to be correct. See his quote below, from the FG60R3 thread... I think he may have nailed it!
I look for a 3 cylinder radial with the FG-61T geometry next. FG-92R3
#556
I wouldn't hold your breath for the FG92R3, either, if they are making an FG90R3... now if this is a prototype and they are looking at all options, then.... maybe.
The point of my comment was that hpergm seems to have called it long ago...
Last edited by slither; 08-02-2016 at 05:22 PM.
#557
Senior Member
Ray's mods would be new on the 450, as would converting to gas. That being said, I wouldn't expect that anytime soon.
I wouldn't hold your breath for the FG92R3, either, if they are making an FG90R3... now if this is a prototype and they are looking at all options, then.... maybe.
The point of my comment was that hpergm seems to have called it long ago...
I wouldn't hold your breath for the FG92R3, either, if they are making an FG90R3... now if this is a prototype and they are looking at all options, then.... maybe.
The point of my comment was that hpergm seems to have called it long ago...
#558
Sorry I missed that... I remembered that someone had said it and his was the first reference I came across when I looked. OK, so SrTelemaster150 and hpergm both nailed it! Good call!
#559
Senior Member
By doing this, Saito is skirting any kind of design liability for the FG-84R3 faults.
Last edited by SrTelemaster150; 08-05-2016 at 02:21 PM.
#560
My Feedback: (6)
Ok, so I've read through this thread and found a lot of good info. However that was a while ago, I just want to make sure my FG33 is doing it's "normal" performance issues.
So first one is that the #1 cylinder valves (especially the exhaust) are pretty much dry. Bearly no oil when I pull off the valve covers. While 2 and 3 are soaked.
I am running a touch more then the recomended ratio using Red Line 2 stroke oil. Cylinder temps are not as far off as I would have thought. Got about 15 C spread between #1, and #2(could be 3, I forget which one I put the temp prob on) and #1 is hitting about 135 C (275 F) on the ground during sustained high power running, and it can peak at that in flight as well if I do any prolonged full power flying.
I am running a Xoar WWII 17x8 prop and I am getting about 7900 RPM on the ground. With a Keleo exhaust.
Neddles are set to about 1 1/4-1 1/2 on the high, and I tried 7 1/2 on the low but noticed a hesitation on transition and a slow return to idle so I set it to about 7 3/4. With those settings idle is decent, and transition is just ok with mideocer mid range.
So from what I am reading this seems to be par for the course, what I am most concerned with though, is the lack of oil on the #1 valves. This is what I would like most to remedy. I have my 33 installed on a hangar 9 20 cc Corsair, so gettin every last RPM out of it is not a huge priority. Just want to make sure it stays lubed and reliable.
So first one is that the #1 cylinder valves (especially the exhaust) are pretty much dry. Bearly no oil when I pull off the valve covers. While 2 and 3 are soaked.
I am running a touch more then the recomended ratio using Red Line 2 stroke oil. Cylinder temps are not as far off as I would have thought. Got about 15 C spread between #1, and #2(could be 3, I forget which one I put the temp prob on) and #1 is hitting about 135 C (275 F) on the ground during sustained high power running, and it can peak at that in flight as well if I do any prolonged full power flying.
I am running a Xoar WWII 17x8 prop and I am getting about 7900 RPM on the ground. With a Keleo exhaust.
Neddles are set to about 1 1/4-1 1/2 on the high, and I tried 7 1/2 on the low but noticed a hesitation on transition and a slow return to idle so I set it to about 7 3/4. With those settings idle is decent, and transition is just ok with mideocer mid range.
So from what I am reading this seems to be par for the course, what I am most concerned with though, is the lack of oil on the #1 valves. This is what I would like most to remedy. I have my 33 installed on a hangar 9 20 cc Corsair, so gettin every last RPM out of it is not a huge priority. Just want to make sure it stays lubed and reliable.
#561
Senior Member
hpergm early on suggested that rather than taking the FG84R3 off the market and fixing it, Saito would make a different version with Ray's fixes and the 84 would disappear... looks like that will turn out to be correct. See his quote below, from the FG60R3 thread... I think he may have nailed it!
My prediction was to base the engine on the existing FG-84 with an FA-180 stroke. That would have resulted in an FG-87 (no the FA-180 isn't a 1.8 cu in engine but 1.77 cu in (29.1cc)
Instead they used the FG-61T bore & kept the FA-450 derived bottom end. The FG-61T has a slightly longer stroke hence the 30.5cc per cylinder.
Doing that absolved them of admitting that the FG-84 was a flawed design.
Last edited by SrTelemaster150; 09-12-2016 at 04:06 AM.
#564
+30 flights on my stock engine.
Overshot the runway on my last flight during landing, and broke my prop.
Paint on my stock exhausts is falling off.
But it runs great, and sounds fantastic
Overshot the runway on my last flight during landing, and broke my prop.
Paint on my stock exhausts is falling off.
But it runs great, and sounds fantastic
#565
Senior Member
Ray's mods would be new on the 450, as would converting to gas. That being said, I wouldn't expect that anytime soon.
I wouldn't hold your breath for the FG92R3, either, if they are making an FG90R3... now if this is a prototype and they are looking at all options, then.... maybe.
The point of my comment was that hpergm seems to have called it long ago...
I wouldn't hold your breath for the FG92R3, either, if they are making an FG90R3... now if this is a prototype and they are looking at all options, then.... maybe.
The point of my comment was that hpergm seems to have called it long ago...
HERE IS MY POST from 8/7/15 and THIS WAS THE RESPONSE from a HH rep.
#566
Join Date: Jun 2002
Location: WY
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
I three 170 R3's, 1 200 and 2 450's The 200 and a 450 are being modified by Ray now. I also have an OS 7 cyl on which I have CH ignigion. I have experimented using mix of Gas and glo fuel up to 50-50. It works fine with only slight increase in needle sensitivity. Intend to try on the 450.
Don T Newcastle WY
Don T Newcastle WY
#567
Senior Member
Join Date: Apr 2005
Location: goolwasa, AUSTRALIA
Posts: 1,680
Likes: 0
Received 0 Likes
on
0 Posts
I three 170 R3's, 1 200 and 2 450's The 200 and a 450 are being modified by Ray now. I also have an OS 7 cyl on which I have CH ignigion. I have experimented using mix of Gas and glo fuel up to 50-50. It works fine with only slight increase in needle sensitivity. Intend to try on the 450.
Don T Newcastle WY
Don T Newcastle WY
#571
#572
My Feedback: (156)
it was this kit Polikarpov I16 "RATA" (Mosca)
Way to heavy. 200cm vs and 12kg
Way to heavy. 200cm vs and 12kg
but I do not see RETRACTS offered? What did you use for landing gear?
#573
I used this retract Electric Retractable Landing Gear for Main Wheel Servoless RC aircra PZ-15096B # eBay
and legs from unitracts
But I dont recomend this kit. it is nice but heavy. almost immpossible to land. it will tipstall if you try to fly slower than 60km/t
I have startet on a new one. in wood. from a drawing by peter kriz. it is 2.3meter an I will use the fg84.
and legs from unitracts
But I dont recomend this kit. it is nice but heavy. almost immpossible to land. it will tipstall if you try to fly slower than 60km/t
I have startet on a new one. in wood. from a drawing by peter kriz. it is 2.3meter an I will use the fg84.