Originally posted by Splais
Bax,
I'm getting a new 1.40RX. I have a couple of questions on proper break-in.
The manual states:
"Start the engine and open the throttle. Close the needle-valve gradually and allow the engine to run at its maximum rpm for just one or two seconds, then immediately reopen the needle-valve a half turn and run the engine with this rich mioxture for 5 to 6 seconds. Repeat until tank is empty.......not more than 10% nitro."
Here are my questions:
1. I only have 15% Cool Power available. Can I use it or do I have to wait until I can find some 10%.
2. The above sounds like you start the engine, run it up to full throttle, then go crazy playing with the needle going back and forth until the tank is empty. Is this correct - wide open throttle.
3. If I do this one tank ground break-in, can I then go direct to flying and just keep it tame for a couple of tanks.
4. Any general comments on break-in are really appreciated.
Thanks, Steve.
I'd do as the manufacturer recommends when it comes to nitro - if it says 10% or less than that's what I'd use....
As far as the breakin procedure, it is all done at wide open. If you're using the OS pipe, it's a little wierder. The motor will fall on and off the pipe as you lean and richen the mixture according to the instructions.
When I did the breakin on my 1.40 (now R.I.P.), there was a hair-trigger spot in the needle setting - one click or so leaner and the motor jumped on the pipe and ran at a howling 2-stroke, two or three clicks richer and it'd fall off the pipe and run at a super sloppy 4-stroke..... Like I said, that spot was hair trigger and made it very difficult to cycle the motor between 2-cycle and 4- or more cycle operation for the breakin. Also, the needle setting when the motor is on the pipe is very broad - i.e., close to an entire turn of the needle and the motor is still on the pipe and running pretty much at the same rpm. But to get it to 'fall off' the pipe and go back to rich running was only a couple clicks or so....
Made the breakin kind of a fight for me.....
If I had it do over again (and I might since I might be buying another 1.40), I'd do the breakin on a standard muffler instead so I don't have to chase the needle like that.
Mine only lasted for about 10 flights before the main bearings went rough like there was sand in the motor, so I had to take it out of service (and then I sold the plane).
Pretty sure my copy was defective though, probably one that sat on Tower's shelf for a year or so gathering rust on the bearings before I finally bought it from them......
But man what a motor..... unreal power and quiet as a lion stalking her prey.......
LS