UMS Gas Radial Engine Enthusiasts Rabbit Hole
04-18-2022, 03:52 PM
#1
UMS Gas Radial Engine Enthusiasts Rabbit Hole
Here goes Tom. Thanks for helping me start the new thread.
Aaron (Hyjinx)
My new UMS 125 from CH ignitions in Florida USA.
Brand new UMS 125 in a new to me Waco 60 Arf. Un started as of yet 4/18/22.
Thanks to anyone who is interested in sharing info on the current design UMS Gas Radials....
Aaron (Hyjinx)
My new UMS 125 from CH ignitions in Florida USA.
Brand new UMS 125 in a new to me Waco 60 Arf. Un started as of yet 4/18/22.
Thanks to anyone who is interested in sharing info on the current design UMS Gas Radials....
Last edited by Hyjinx; 04-18-2022 at 04:52 PM. Reason: Prono
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wmoutlaw (10-17-2023)
04-18-2022, 05:23 PM
#2
My Feedback: (62)
Well done Aaron!
I hope this thread comes alive.
The UMS 5-100; I now have 15 8 oz tanks of 40;1 redline ethanol free gas/ oil with 2 oz of Sea foam/ gallon. Nearly perfect carburation through the entire range from 600 rpm to 4500 turning a Xoar 25x12 prop. True horsepower is 4.65. Think of a DA50 with belt reduction. A Moki 215 is 9.5 Hp at 4000 rpm...This engine is very easy to start. The mid throttle is slightly lean but a lightly rich setting at idle takes care of that. No blubber rich areas through the throttle range. All cylinders run evenly!!! My UMS 5-55 and 5-100 do run rather hot at 230 F. The APS power fuel fuel pump is required (5-100).
The UMS 5-100; I now have 15 8 oz tanks of 40;1 redline ethanol free gas/ oil with 2 oz of Sea foam/ gallon. Nearly perfect carburation through the entire range from 600 rpm to 4500 turning a Xoar 25x12 prop. True horsepower is 4.65. Think of a DA50 with belt reduction. A Moki 215 is 9.5 Hp at 4000 rpm...This engine is very easy to start. The mid throttle is slightly lean but a lightly rich setting at idle takes care of that. No blubber rich areas through the throttle range. All cylinders run evenly!!! My UMS 5-55 and 5-100 do run rather hot at 230 F. The APS power fuel fuel pump is required (5-100).
Last edited by Maxam; 04-18-2022 at 05:25 PM. Reason: Omission.
04-18-2022, 05:52 PM
#3
I am running a UMS 5-100 on a 1/5th scale Ziroli AT-6 Texan although I haven't done the maiden yet. Long story about that but the maiden probably won't happen till the end of the year. As Tom has stated, the 5-100 is an easy to start, smooth running engine. I am turning a semi-scale Biela 25x14, turning 4400rpm's.
The following 4 users liked this post by okcrcpilot:
04-18-2022, 07:45 PM
#6
I hope this thread comes alive.
The UMS 5-100; I now have 15 8 oz tanks of 40;1 redline ethanol free gas/ oil with 2 oz of Sea foam/ gallon. Nearly perfect carburation through the entire range from 600 rpm to 4500 turning a Xoar 25x12 prop. True horsepower is 4.65. Think of a DA50 with belt reduction. A Moki 215 is 9.5 Hp at 4000 rpm...This engine is very easy to start. The mid throttle is slightly lean but a lightly rich setting at idle takes care of that. No blubber rich areas through the throttle range. All cylinders run evenly!!! My UMS 5-55 and 5-100 do run rather hot at 230 F. The APS power fuel fuel pump is required (5-100).
The UMS 5-100; I now have 15 8 oz tanks of 40;1 redline ethanol free gas/ oil with 2 oz of Sea foam/ gallon. Nearly perfect carburation through the entire range from 600 rpm to 4500 turning a Xoar 25x12 prop. True horsepower is 4.65. Think of a DA50 with belt reduction. A Moki 215 is 9.5 Hp at 4000 rpm...This engine is very easy to start. The mid throttle is slightly lean but a lightly rich setting at idle takes care of that. No blubber rich areas through the throttle range. All cylinders run evenly!!! My UMS 5-55 and 5-100 do run rather hot at 230 F. The APS power fuel fuel pump is required (5-100).
04-18-2022, 07:48 PM
#8
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mchandrayan (04-20-2022),
NavyE6FE (04-06-2023)
04-19-2022, 04:18 AM
#11
Do you watch temperature on cowled and open air set ups? Seeing both, I wonder if the Texan rums hotter? Assuming the same oil mix and octane rating and non ethanol gas blends....
04-19-2022, 04:40 AM
#12
I no longer monitor head temps on the 260 since I have a lot of flights on her. Since I fly Spektrum I am using their temperature sensor to keep an eye on the 100 in the AT-6. Not having flown the plane yet, I don't know what the readings will be although on the test stand average was 170°
EDIT: Depending on the head temps of the 100-5, I may have to construct some sort of engine baffle. This would be a new undertaking for me so any and all suggestions/recommendations will be appreciated. Also, I used Amsoil Dominator in my radials at a 50:1 ratio and so far have not encountered any problems. I lube everything on the first flight of the day with gear lube.
EDIT: Depending on the head temps of the 100-5, I may have to construct some sort of engine baffle. This would be a new undertaking for me so any and all suggestions/recommendations will be appreciated. Also, I used Amsoil Dominator in my radials at a 50:1 ratio and so far have not encountered any problems. I lube everything on the first flight of the day with gear lube.
Last edited by okcrcpilot; 04-19-2022 at 05:35 AM. Reason: Update
04-19-2022, 04:43 AM
#13
My Feedback: (62)
GI Jon, yes I did. I hope the O-rings last with gasoline. Neat little engine. (5-55)
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
Last edited by Maxam; 04-19-2022 at 04:45 AM. Reason: Omission.
04-19-2022, 05:05 AM
#14
GI Jon, yes I did. I hope the O-rings last with gasoline. Neat little engine. (5-55)
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
04-19-2022, 05:37 AM
#15
GI Jon, yes I did. I hope the O-rings last with gasoline. Neat little engine. (5-55)
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
One other thing I like about the 5-100, still uses the little glow size spark plugs. I talked to Adrian about the thick R-Excel spark wires that are cumbersome especially on the smaller engines. He said the thinner wires do not work well with a hot spark.
To anyone interested. I have completed my Schlundt 46% Bowers Fly Baby using a Moki 257.
Nice Texan and Stearman and Waco!
-Tom
PS Great title for the thread!
Gary
04-19-2022, 08:22 AM
#18
I no longer monitor head temps on the 260 since I have a lot of flights on her. Since I fly Spektrum I am using their temperature sensor to keep an eye on the 100 in the AT-6. Not having flown the plane yet, I don't know what the readings will be although on the test stand average was 170°
EDIT: Depending on the head temps of the 100-5, I may have to construct some sort of engine baffle. This would be a new undertaking for me so any and all suggestions/recommendations will be appreciated. Also, I used Amsoil Dominator in my radials at a 50:1 ratio and so far have not encountered any problems. I lube everything on the first flight of the day with gear lube.
EDIT: Depending on the head temps of the 100-5, I may have to construct some sort of engine baffle. This would be a new undertaking for me so any and all suggestions/recommendations will be appreciated. Also, I used Amsoil Dominator in my radials at a 50:1 ratio and so far have not encountered any problems. I lube everything on the first flight of the day with gear lube.
04-19-2022, 10:37 AM
#20
Thanks for the suggestion Tom. I wish I would have asked this question before mounting the engine on the plane!!! Oh well, it'll give me something to do the next time it rains!!! Thanks for posting pictures of your "Baby". I'll best she flys like a dream.
04-19-2022, 05:27 PM
#21
UMS Radials…
I’m on my second UMS made radial, this one the 5-150 going on the TopRCModel P-47 96”. Plan on flying a SEP 23X14X4.
My UMS engine is the Tomahawk branded “Blackstar” 5-250 which I picked up bundled with a 1/3 scale Tomahawk Wilga. My experience with this engine along with Adrain’s support shifted me to this brand.
I run them both, as well as my (2) Moki 250’s & (1) Moki 215 on the APS fuel pump. They run strong, sound great and with the exception of the pump, require no changes out of the box. My Moki’s required switching ignitions, disconnecting the fuel pulse pump and don’t support RPM telemetry.
Cheers
My UMS engine is the Tomahawk branded “Blackstar” 5-250 which I picked up bundled with a 1/3 scale Tomahawk Wilga. My experience with this engine along with Adrain’s support shifted me to this brand.
I run them both, as well as my (2) Moki 250’s & (1) Moki 215 on the APS fuel pump. They run strong, sound great and with the exception of the pump, require no changes out of the box. My Moki’s required switching ignitions, disconnecting the fuel pulse pump and don’t support RPM telemetry.
Cheers
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rgoinbroke (07-17-2023)
04-20-2022, 10:28 AM
#25
I’m on my second UMS made radial, this one the 5-150 going on the TopRCModel P-47 96”. Plan on flying a SEP 23X14X4.
My UMS engine is the Tomahawk branded “Blackstar” 5-250 which I picked up bundled with a 1/3 scale Tomahawk Wilga. My experience with this engine along with Adrain’s support shifted me to this brand.
I run them both, as well as my (2) Moki 250’s & (1) Moki 215 on the APS fuel pump. They run strong, sound great and with the exception of the pump, require no changes out of the box. My Moki’s required switching ignitions, disconnecting the fuel pulse pump and don’t support RPM telemetry.
Cheers
My UMS engine is the Tomahawk branded “Blackstar” 5-250 which I picked up bundled with a 1/3 scale Tomahawk Wilga. My experience with this engine along with Adrain’s support shifted me to this brand.
I run them both, as well as my (2) Moki 250’s & (1) Moki 215 on the APS fuel pump. They run strong, sound great and with the exception of the pump, require no changes out of the box. My Moki’s required switching ignitions, disconnecting the fuel pulse pump and don’t support RPM telemetry.
Cheers
Looking at a non Chinese Arf of a Bucker Jugenmeister single seat. The cz is Chinese unfortunately, so it's ruled out at this point. Please continue to post your experience with the UMS Tomahawk. Thanks Aaron-