Ball bearing problems

you should only be running 15% in high performance or cold weathe

applications. with a trainer type of aircraft you only need 5% and tun it a little rich on the ground as it will lean out once you ar airborn

-- papama

----------------------------------------------------------------------- papamac's Profile:

The last I heard, Cool Power used about 16% all-synthetic oil. Your

Jim - AMA 501383

MAYBE NOT ENOUGH LUBE IN THE COOL-POWER FUEL ( or maybe no lube )

Run the engine slobbering rich and check for oil-residue from muffler You'll see the proble

-- hall wo

----------------------------------------------------------------------- hall woo's Profile:

This seems to be more and more common with engines running Cool Power. I just sold 4 sets of ceramic bearings to some heli fliers using the OS 50 SX-H engines who had exactly the same problem. My advice would be to make sure you use a rear bearing with a high speed plastic retainer and run a fuel other than Cool Power.

the 50 sx is a ringed engine....unlike the abc engines that must be run in 2 cycle to come up to temp for proper piston cylinder fit a ringed engine should be broke in 4 cycle at first then after a few tanks to 4 cycle breaking into 2 cycle (plenty rich) I suspect a lack of lube and a 12 x 6 prop seams to be on the large side (too high of load...too much heat) for this engine it might be ok after breaking in on a smaller prop, by running a smaller prop for break in it will run at a higher rpm and what comes with that is a lighter load with more fuel that come with more oil which carries away the heat as well as more lubrication I have read the Os manual and see that they recommend a 12 x 6 but personal experience with my 50 sx has shown that a 11 x 6 is a much better choice for this engine... mine is 3 years old and I have run 11 gallons of power master 15 % thru it and it still has original bearings and is still as strong and smooth as ever....I ran the first 3 tanks in full 4 cycle then the next 5 in a 2 - 4 break and since then in a semi rich 2 cycle all with apc 11x6

This is speculation on my part, but it appears that you are in Belguim, so do you perchance have engines designed for use with 0% nitro, which will have higher compression than an engine designed for nitro? 15% nitro in a high compression engine swinging a large prop, and using inadequate oil in the mix is bound to spell disaster.

Paul McIntosh, you surely know whether OS and Magnum suppliy European engines with higher compression than US engines. Let us know!

Geoff Sanders

Therein lies the difference. You used Powermaster which has a very good lube package.

They are all the same. Many of the Brits complain about the performance on low/no nitro fuels with the Japanese and Chinese engines. Many of them are now seeing that the engines are designed for the mass market (US).

Just another thought. If the chrome came off the balls, they you have a real big problem! The balls are solid chrome-steel, not plated!