MOKI RADIAL Care and Maintenence
10-05-2018, 09:44 AM
#4201
My Feedback: (1)
Two years ago I bought a Moki 250 for a comp arf F4-U i was building. Initial test running on a test stand was not satisfactory. it wasn't possible to get the high speed mixture rich enough (turn the needle out three or more turns no drop in rpm). I settled for this, finished the airplane and installed the engine and test flew. However, the Moki quit frequently, once in flight, and was just very temperamental. I started reading others comments in this forum and found out that many were having similar problems. At one point V.A. came out recommending an electric fuel pump. To me, this was an admission from the factory rep. that the engine had issues. Finally, out of total frustration, I discarded the factory Walbro carb. In it's place I used an O.S. Max 8B carb I had in my "junk box" (I believe O.S. used this on their 108 motor). GUESS WHAT! All problems disappeared. I use no pump of any kind, not even muffler pressure. The throttle response is much more linear and CH temps have dropped from somewhere around 250F to less than 200F (Jeti telemetry). I've had many flights on the Corsair since making this change and I no longer have any concerns about the engine stopping in flight or any other time.
Thanks...
10-05-2018, 01:11 PM
#4202
My Feedback: (4)
Join Date: Dec 2001
Location: Dayton, OH
Posts: 358
Likes: 0
Received 0 Likes
on
0 Posts
Yes, this carburetor is probably not available. But I,m sure that any nitro R/C two stroke carb of similar size will work. One that comes to mind is the Moki 180/210 engine carb, a very high quality unit by the way.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
10-05-2018, 01:17 PM
#4203
My Feedback: (1)
Yes, this carburetor is probably not available. But I,m sure that any nitro R/C two stroke carb of similar size will work. One that comes to mind is the Moki 180/210 engine carb, a very high quality unit by the way.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
- if the two engines share the identical carb
- if either the 215 or 250 has demonstrated a greater difficulty to tune / keep running reliably.
10-05-2018, 06:05 PM
#4204
My Feedback: (4)
Join Date: Dec 2001
Location: Dayton, OH
Posts: 358
Likes: 0
Received 0 Likes
on
0 Posts
Just read the posts.This forum topic goes back to 2009. And from the beginning a lot of the posts had to do with how to adjust the needle valves properly, how to prevent overheating, the necessity of keeping the impulse line free of grease, and so on. The only "fix" the factory could offer was the electric fuel pump which is expensive, must run all of the time, and probably is going to require an additional battery pack. And this "fix" doesn't really address the main problem. It is merely a substitute for the Walbro pump which is relatively trouble free and requires no electric power. Eliminate both these problems- get a two stroke nitro carb.
10-05-2018, 06:11 PM
#4205
My Feedback: (569)
Yes, this carburetor is probably not available. But I,m sure that any nitro R/C two stroke carb of similar size will work. One that comes to mind is the Moki 180/210 engine carb, a very high quality unit by the way.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
The main problem with the Walbro is that the carb throat is too large, this. causes a very weak DELTA P in the venturi. The throat area of the O.S. carb is 62 pct. of the Walbro.
Bill
10-08-2018, 11:49 AM
#4206
Advice please. I have a Moki 250. It will fit into the cowl of the Vailly Tempest 2 which is 1/5th scale.
Is is this a practical combination?
D G.
Is is this a practical combination?
D G.
10-09-2018, 12:12 AM
#4208
Thanks , Mick. I was just wondering if it might be rather small.
Most of the other kits for the 250 seem to be 1:4.5 or larger so I suspected the Tempest may just be a little small for what is a very powerful and heavy (mine is electric start) engine.
I have the Vailly kit so work will begin!
DG.
Most of the other kits for the 250 seem to be 1:4.5 or larger so I suspected the Tempest may just be a little small for what is a very powerful and heavy (mine is electric start) engine.
I have the Vailly kit so work will begin!
DG.
10-12-2018, 07:59 AM
#4209
Join Date: Jan 2018
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Help please: I have a Moki S180 with the blue ignition unit, the engine was running but when I went to restart it there were no green lights on the ignition unit. I tested that there was power going to the unit, is it faulty?
Many thanks
John
Many thanks
John
10-30-2018, 10:36 AM
#4212
Looking for Tubulator
Hey guys. I'm looking to see if anyone out there has a kunkel turbulator they bought for there 215 or 250 that is not being used. Vogelsang does not have any in stock. So if you have one sitting around that you do not have a use for please drop me a line. [email protected]
Thanks
Thanks
Last edited by TSHARK203; 10-30-2018 at 10:39 AM. Reason: Added title
11-02-2018, 04:49 PM
#4213
My Feedback: (65)
Join Date: May 2010
Location: New York
Posts: 256
Likes: 0
Received 0 Likes
on
0 Posts
Can someone please help me with the size tank needed for a Moki 180cc in a Meister jug please.
64ounces fits fine as well as a 32 ounce.
What are most getting for flying time hauling the mail with the 32's?
Thanks
64ounces fits fine as well as a 32 ounce.
What are most getting for flying time hauling the mail with the 32's?
Thanks
Last edited by kork; 11-02-2018 at 04:51 PM.
11-03-2018, 02:15 AM
#4216
My Feedback: (65)
Join Date: May 2010
Location: New York
Posts: 256
Likes: 0
Received 0 Likes
on
0 Posts
Thanks guys, I realized the larger Fuji bottle is 50 ounces instead of 64 like I thought.
I will probably stick the 32 in it then.
Im looking for a good 8 minute flight is all.
I will probably stick the 32 in it then.
Im looking for a good 8 minute flight is all.
11-15-2018, 10:43 AM
#4218
My Feedback: (10)
Join Date: Oct 2010
Location: Pittsburgh,
PA
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
Hopefully I am in the correct form . I need some help identifying a Moki 5 cylinder radial that came with a Bipe that I recently purchased. It is stamped 250415. I guessing that it's a 250 and the 415 is a serial. I purchase this and several other giant scales from a lady who's husband has passed. I'm new to Moki and intend on following this form. I have a lot to learn and more questions to come.
11-20-2018, 07:18 PM
#4220
electric fuel pump
Well I was getting frustrated with the amount of flipping the prop to get the 250 primed. Raised the fuel tank, installed a pump and now happy chappy. Pump on, ign on, full choke 3-4 flips motor fires, choke off 3-4 flips and motor running fine.
Thanks to all help and advice on this thread.
tmac48.
Sorry wrong photo.old pic with DA 150.
Thanks to all help and advice on this thread.
tmac48.
Sorry wrong photo.old pic with DA 150.
Last edited by tmac48; 11-20-2018 at 07:24 PM.
11-23-2018, 02:17 AM
#4221
Hi Guys, I am looking to squeeze a Moki 250 into a Warbird I am working on. I have a spec sheet for the 250 that indicates the diameter is 285mm or 11.22 inches. What I need to know is what is a real number for the inside diameter of a cowl, allowing for rocker arms to move & the barest minimum of clearance?
Thanks in advance,
Mick
Thanks in advance,
Mick
01-06-2019, 08:50 AM
#4222
MOKI Radial general maintenance
Hi Guys,
If you want to see my guys in action (and with photos) about a MOKI S250 radial maintenance, please go to my Professional FaceBook webpage :
https://www.facebook.com/ModelismeMicromoteursService/
Hope this help you if you want to work on your lovely radial engine !
Happy New Year 2019 for you and your Families
Olivier
If you want to see my guys in action (and with photos) about a MOKI S250 radial maintenance, please go to my Professional FaceBook webpage :
https://www.facebook.com/ModelismeMicromoteursService/
Hope this help you if you want to work on your lovely radial engine !
Happy New Year 2019 for you and your Families
Olivier
02-10-2019, 02:31 PM
#4223
Join Date: Jul 2011
Location: West Richland, WA
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Guys, I need a little help. I am mounting an old 215 MOKI to the firewall of a 41% Pitts Model 12 biplane. My current question is about how best to control the choke on the MOKI. As you are aware, the choke is about flush with the rear of the mounting bell, so very near the firewall. It appears the control rod (with ball link) needs to exit to the rear of the engine through the large hole in the firewall? I'd prefer to open and close the choke manually without a servo, but not sure I know how best to install all the linkage. Can some of you experienced MOKI users show or state how best to do this. The engine is covered with a round cowl, so I'd need the pushrod for actuation must be outside the cowl, or maybe inside the cockpit area. The cockpit area is covered with a canopy, so something under the fuse would likely be best?
Thanks,
Larry Fitcfh
Thanks,
Larry Fitcfh
02-10-2019, 03:51 PM
#4224
My Feedback: (2)
Guys, I need a little help. I am mounting an old 215 MOKI to the firewall of a 41% Pitts Model 12 biplane. My current question is about how best to control the choke on the MOKI. As you are aware, the choke is about flush with the rear of the mounting bell, so very near the firewall. It appears the control rod (with ball link) needs to exit to the rear of the engine through the large hole in the firewall? I'd prefer to open and close the choke manually without a servo, but not sure I know how best to install all the linkage. Can some of you experienced MOKI users show or state how best to do this. The engine is covered with a round cowl, so I'd need the pushrod for actuation must be outside the cowl, or maybe inside the cockpit area. The cockpit area is covered with a canopy, so something under the fuse would likely be best?
Thanks,
Larry Fitcfh
Thanks,
Larry Fitcfh
I extended the choke arm about 1 inch so the ball link and 4-40 rod is just aft of the mounting ring. I put a coupling on the end of the rod so that a 2nd rod could be screwed into the rod to remove the cowl. I chose to exit the top left of the cowl. Choke open was down and flush with the cowl. To choke - pull up the rod. Hope this helps.
Regards - J Tab
02-10-2019, 05:50 PM
#4225
Join Date: Apr 2006
Location: kuwaitkuwait, KUWAIT
Posts: 23
Likes: 0
Received 0 Likes
on
0 Posts
Guys, I need a little help. I am mounting an old 215 MOKI to the firewall of a 41% Pitts Model 12 biplane. My current question is about how best to control the choke on the MOKI. As you are aware, the choke is about flush with the rear of the mounting bell, so very near the firewall. It appears the control rod (with ball link) needs to exit to the rear of the engine through the large hole in the firewall? I'd prefer to open and close the choke manually without a servo, but not sure I know how best to install all the linkage. Can some of you experienced MOKI users show or state how best to do this. The engine is covered with a round cowl, so I'd need the pushrod for actuation must be outside the cowl, or maybe inside the cockpit area. The cockpit area is covered with a canopy, so something under the fuse would likely be best?
Thanks,
Larry Fitcfh
Thanks,
Larry Fitcfh
yeah same as above, come straight out the back of the firewall about an inch or so and use a 90 degrees bell crank and come out the side of the plane. We use the dubro bell cranks for throttles on gas boats aswell and are very reliable.