I have a Moki 1.35 that I'm trying to break in. Motor will be running fine(real rich) then just die. I ran 3 tanks of fuel through it today, died 3-4 times each tank. It's mounted on stand and I was using a cline pump. Any suggestions.

Hey:

Try removing the Cline system until the engine is thoroughly broken in. The tendency to die is probably due to over-heating, also be sure to use an OS type "F" plug --- try richening the idle disk slightly --- try adding a few extra ounces castor oil to your fuel

Hope this helps; however the Moki 135 carb has been known to give problems !

Engine would't hardly run at all untill I put on the cline pump also when engine is cool enough you can hold on to the head & cyl. It's warm but not enough to burn. I've messed with low side, doesn't seem to make much difference. If I richen much you can't start it. The fuel I'm running is 20% oil, byron

I hope you are FAI (0% Nitro). My Moki's don't run will with over 5% nitro. I have had good luck with a K&B 1L plug. Also break-in takes a lot of fuel but then they run great.

Running 10%, that's what I run in my 1.8. They say it will run on it. Right now I'm lost

5% max for the Moki, unless you want to chase the needle forever. I would take the cline off until you get the engine running properly. The K&B 1L or any other cold plug should also be used. The low end should have a great impact, if you are not getting much of a change pull the disc out and make sure the metering holes are in alignment. I've found quite a few need to be shimmed to work properly.

Mark M.

2 wing pilot,

Excuse me, but are you doing the break-in per the instructions that came with the engine? Is your fuel delivery system as per the instructions? My instructions are of the Gerard Enterprises version from 1999. Are yours from Gerard Ent. or from Horizon Hobbies? What numbers are stamped on the right engine lug that would indicate what year it was manufactured? Have you re-started the break-in procedure from scratch? I mean from a closed HS needle valve to the number of turns that the instructions suggest and up to the suggested RPMs for the suggested duration of time and tank fulls. Sorry, I just gotta know more than what I have read so far. Which is really not much to make a fair diagnosis.

Anyway. Here's my setup. A JTEC aluminum motor mount; Bisson Pitts-style muffler with one exhaust stack; a Menz or APC 16X8 prop; medium Prather fuel tubing; the ends of all fuel lines are clamped on tight with pieces of fuel tubing; no fuel filter; OS 4-stroke plug; minimum 16 ounce tank set up with no errors; centerline of fuel tank is no more than 1/4th inch below the needle valve centerline; every screw/bolt on engine and motor mount has been checked for tightness; Power Master 5% fuel; and that's all I can think of right now. I may have left out something.

Could you give me a similar run down? I need more information when trying to help someone. I don't mean to be rude or any such thing.

When you have had the engine running, do you see any bubbles of air passing through the fuel line? What pattern occurs just before it dies? Do the RPMs increase just before dying? Does it come to a halt suddenly? Is there fuel leaking out of the carb or front end of prop washer area? BTW, have you considered your club's engine guru? Every club has one or more REAL gurus. What does he say?

Who did you buy the engine from? If from Horizon or a local hobby shop, then you might have some help there. If in a swap meet, .... h-m-m-m. Do you have the instruction sheet(s) to follow? I can email you a copy of mine in pdf format.

I will be looking for your response in the next few days.

San Antonio Flyer

SA FLyer- My papers came from horizon. Paper doesn't talk about turns on needle valve but talks about 7000 rpm. I never checked the rpm while trying to break it in. My motor was made in 2000 I think. I bought it new from a hobby shop. Running 16x8 apc, 20oz tank mounted slightly higher than your recommendation, brisson pitts style muffler, moki plug, byrons10%with 20%oil. I can't change fuels yet, can't buy anything else locally. With the engine running rich it will die like you flip a switch, no warning. You talked about checking with guru, I'm one of them. Shows what I know. Any help would be helpful. Thanks

WHAT ABOUT THE PLUG SA FLYER MENTIONED? THE PLUG THAT CAME WITH MY 135 WAS A PROBLEM. USE THE OS F PLUG AND TRY AGAIN. THE INSTRUCTIONS THAT CAME WITH MINE GAVE THE HS NEEDLE VALVE ADJUSTMENT.

I threw away the plug that came with the Moki 1.35 and, for now, cannot remember why I did that. Because of the compression of this engine, a hot plug similar to what is used with 4 strokes was recommended. Find any other plug to rule out the plug as the problem.

There is another thread going on where some one in Texas added a modification to his Moki's Low Speed Disk. What it involved was cutting out a shim (washer) out of material from a common plastic milk jug. The reason for that was to resolve a problem with the engine cutting out while in flight. The shim lines up the hole in the disk with the long groove cut into the throttle bar (or whatchamacallit). I have cut out and installed the shim, but have yet to fly the Moki. After changing out the plug, you might want to try that.

SA Flyer

Reprint:

Well,

I finally got around to breaking in my Moki 1.35. After 1.5 gallons of FAI 80/20 the top end started picking up very well. However, I had a lot of difficulty setting the midrange. The adjustment disk was not allowing me to richen the midrange without killing the topend. I followed MMallory's instructions (on this thread) and shimmed the mid range adjustment disk 1/32nd out from the carb body ( plastic washer cut from coffee can lid). The transition is much better! It's still not perfect but very close.

FYI: MAX RPM now at 9000 with APC 16x8
MIN IDLE: 1700 rpm

"stable operating range" 2000 to 8800 rpm transition slightly rich
midrange disk set: two notches CCW

Bisson standard muffler
Powermaster FAI 80/20 0% nitro
OS F plug


TX

I finally got enough spare time to get back to my 1.35. The only thing I really changed was the plug. Went to OS F plug. Ran 60 ounces through it and never had a problem. Think its time to put back in plane. I have nice idle and it transitions pretty good. Not instant but just a touch rich. If I lean it any more its harder to start and it acts to lean on the low side. Thanks to all who expressed their opinons, they were alot of help.

SA Flyer,

How did your Moki 1.35 work with the shim installed?

TX

Was at the field today and a fellow flier had a new Moki that would not run in the proper direction for anything. I went home and got the carb off of mine (been down the awful carb road) to try, and the same thing. This engine will run and transition beautufully in reverse?? I'm decent at getting an engine to perform, but this one won't even run. Is there a way to tell if it was meant to run as a pusher or something? He was frustrated and disappointed to say the least. I am going to make this a seperate post but wanted to put it here first. Thanks_bob

SA flyer- Didn't have to go that far. Looks mine will do fine without it. It may change later but for now its good to go. Thanks As far as backward- first question- are you flipping it backward against compression? As far as I know mine has never started and run backward. I've had smaller engines do it but only when I flipped through right way.

didn't notice it mentioned...with the Cline regulator, the regulator has to be AS CLOSE AS POSSIBLE to the carb, 1/2" or less is great!

Also, firm believer in the K&B 1L plug...

Just went through this all on my Moki 1.35...now, to get to the 1.8!!

Gotta love them Moki's!!!!

Anyway, glad you can see light at the end of the tunnel!

The hurricane weather has not allowed me to go out to the field. When it is good enough to fly, I happen to be at work. Rats! Today, the sky looked beautiful but the tree limbs were bending to the point that I felt flying was not a good idea.

Yes, mine does start backwards at least once an outing to the flying field. It doesn't correct itself though, and therefore has to be shut down to restart. I cannot clearly remember the circumstances, but I think it had to do with over-priming and not doing the backward flip of the prop. Sometimes, moving the throttle back and forth works.

I don't recall for sure, but I think that I did read that the engine is available as a pusher version.

My initial problem with the Moki was that it would stop running minutes after becoming airborne. Oh it transitioned impressively on the ground, but not in the air. It was more prevalent when starting a vertical climb. Such as a loop or stall turn. A fellow Moki owner in Wisconsin was experiencing the same issue. He tried lots of different ideas and suggestions on his Edge 540.

Mr. Gerard had suggested that I try my initial tuning with about 4 ounces of fuel in the tank so as to simulate the last few minutes of a flight which was related to something he referred to as fuel weight. That is, fuel pushing down and out of the tank, (not his exact words but my own). The HS needle valve was to be leaned until 9,000 rpm was reached, and then, it was to be backed off about 300 rpm to compensate for the beginning part of the fuel capacity. I am not an engineer or scientist and therefore cannot explain his entire script of instructions. On a different and larger engine that I have, our engine guru set the needle valve utilizing the same procedure which gave me one sweet running engine.


I would hope that Mr. Jim Gerard would read this post and put his instructions in for me and others to copy/paste.

Lupe (SA Flyer)

Turns out that my buddy must have a different crank in his engine When put side by side, my crank opens at just before compression at TDC, and his is past that point and is closed. Very odd to say the least. I took the entine out of my plane and let him use it to get his Aeroworks Freedom 3D going as I am not flying mine right now. These 135's cause alot of wasted flying time as far as I can see_bob

Bob,

Your friend could run a pusher prop on the engine and continue to use it or post a 4-sale on the Jet board. The Kangaroo turbine trainer has a pusher mount so people can get used to the plane before they mount a turbine. I'm sure a pusher 1.35 would sell quickly there.

Mark M.

Since the engine is spank brand new he is going to return it and go from there_bob