I have been bench running a new Moki 2.1. When I got it it had a gallon of fuel through it. I have about 1/2 gallon through it. I can't seem to get the engine to turn more than 5000 rpm at full throttle - is this normal? When the engine nears the bottom of the tank it does come to life as the mixture is leaned but I do not let it run under those circumstances for long.

The high speed needle valve seem to have no effect on the rpm - I have it set to about 3-4 turns. I have not touched the factory setting on the low speed mixture dial. I am using 3/32" fuel line with an inline filter. Pressure is from the muffler. I am using new omega 10% nitro fuel and an OS F plug. It does need to have a glow igniter to keep running.

I have ordered a cline regulator and will be sending the carb in to get some work done by Cline.

Am I going about the break in right?
ScaleMe

Pinching the fuel line resulted in about 7,500 rpm with the needle valve about 4 turns out. Still, leaning the needle valve did not affect the RPM.

You mean that turning the needle valve completely in allows the engine to continue to run? If this is the case you now know why you got the engine after only a gallon was run through it - there's a serious leak somewhere. It should not need to have a glow igniter attached to keep running either. Try turning the needle valve in more than it is now, all the way in until it stops, since the pinch test shows that it is running rich.

OK NewC, I will test it again today and really work the NV setting. I have new fuel line, but I will do a leak test to make sure the plumbing is tight. What RPM should I expect or otherwise strive for during this break in?

ScaleMe

I take it you dont have any paper work? I still have mine if you want any info.i think brake-in is 6000 rpm with a 20-8 prop and wide open throttle.Super rich.Run it for five mins then shut it down and let it cool.Start it all over again.You need at least one hour of time on it.I think thats right.

thanks for the info

Here's from the instructions from my Moki 2.10......

"Moki 2.10 engines have hard chrome cylinders and, therefore, require a modest break-in period. The minimum time is 30 minutes, with best results at 1 hour or more. Make sure that you do not run the engine with a lean mixture during the first 20 - 30 minutes. In fact, it is best to run your engine as rich as possible during the first phases of the break-in procedure. This would be a speed of approximately 6000 RPM with the recommended 20x8 Moki prop. After that, you can lean it out for short periods of time. When the engine will hold a lean setting without slowing, it can be considered broken-in. It is best to use 20% oil, 80 % methanol (FAI) fuel. Small amounts of nitro are OK, but it will make it more difficult to run dependably at the very rich setting without leaving the battery connected. Never attempt to accumulate all of the break-in time in one run. It is always best to run the engine in short runs of 2-3 minutes and let it cool down before starting it again. Do not run at low throttle settings during break-in. Run the engine at full throttle and slow it down by increasing the fuel mixture. Take your time, do it right, and you will have an engine that will last a very long time.

At no time should your Moki engine be operated on straight synthetic oil fuel. Doing so can damage the engine and void your warranty. If castor based fuel is not available, then you must add at least 6 ounces of castor oil (Klotz Bean Oil or equivalent) to each gallon of fuel....."

Thanks for that Newc
ScaleME