Tuning issue
 

OK, OSFSR 60 on a 12x8, 10% nitro and 22% castor/syn fuel. Motor starts and runs fine. Idle to wide open ok on the ground. High speed needle set so when you lift the nose speed picks up slightly. In the air, as long as I am at 3/4 throttle or more engine is fine but if I go to idle back for landing approach (maybe 1/3 throttle) the motor will quit right now. Any idea what I am missing? If I go two clicks on the high it starts to blubber, so I wouldn`t think that the high end is too lean and running hot.

RE: Tuning issue
 

Have you tried an 11X7 or 12X6 prop? Or the low speed may be set a tad too lean.

RE: Tuning issue
 

Your fuel may be bad also? Try the LS needle first.

RE: Tuning issue
 

Skylane,
Sounds like the problem I was having on mu OS 46 LA (see OS 46 LA Dying thread in this forum).
I solved the problem by going to 15% nitro.
I wonder if a hotter plug might give the same result.
KW_Counter

RE: Tuning issue
 

My first instinct is that the midrange needs attention.. I have, what they call the D7 carb on the OS. I use a fox miricle plug.. I like the idle bar plug better. Right now I am doing some repairs on the Wing MGF Hellcat that it is mounted on, so it will be awhile until I can play with it again..

RE: Tuning issue
 

Hi!
I would replace that FOX plug with an Enya 3 or an OS 8 plug first of all.
Have you set the idle mixture? Try that after you have changed glowplugs.

Regards!
Jan K
Sweden

RE: Tuning issue
 

That engine will run best on 15% nitro fuel with some castor, a K&B 1L plug
and an 11-7 1/2 Master Airscrew propeller....balanced nicely. ;)

Trust me on this one....I have been running them continuously for 30 years.

FBD. :D

RE: Tuning issue
 

Skylane,

My first suggestion is to try a fresh plug. Try an OS #8 plug as a reference point and try others if this doesn't work.

The 12x8 is a bit too much prop for the .60 - a good place to start with this engine is an 11x7 or a 12x6.

Your fuel, if fresh, should be fine. My FSR 60 runs quite happily on 80/20 with no nitro.

Good luck - that .60 is a real keeper.

RE: Tuning issue
 

Hi!
When you say that the engine starts to blubber (go rich ) when you open the high speed needle just 2 clicks I get a bit worried about your engines condition (piston to cylinder fit), because using as much as 15% nitro usually mean that you have a very broad needle range (means that the high speed needle could be turned nearly a complete turn without the engine losing much power.
Over here in Europe many of us use only 5% nitro in our engines regardles of make and have no difficulties with our engine settings. Using as much as 15% nitro is overkill for most engines and will sometimes give engine problems due to too high combustion temperature. Your OS is not one of them though and will run fine on 15% nitro But will run just as fine on 5-10% nitro.
It would help us if you could show us some pictures of your engine...and engine set up, and a picture of the cylinder and piston.
Regards!
Jan K
Sweden