OPERATING INSTRUCTIONS - RC World

More documents

Recommendations

Info

Tuning Your Gas Engine using the Spark Plug ColourIn general, engine manufacturers set their engines to run when they leave the factory. This does notmean, they are set at best needle settings, it just means, that the needles are adjusted in a way that theengine will start and run. Obviously, some needle tweeking is required if you want the engine to showwhat it is capable of.Walbro carbs, as well as other carbs without floats, normally have two needles to set. The high speedneedle labeled "H", and the low speed needle labeled "L". The idle needle always is the one closest tothe engine.It is important to keep in mind that the low needle is always active, and that the high needle is only activeabove 1/4 throttle, when there is sufficient low pressure in the venturi for the H needle to start drawingfuel.Here is the drill to start from scratch:idle mixtureOpen both needles L=1.5 to 2.0 turns, H=2 turns. This will ensure a rich setting.Close the choke valve and turn on ignition.Start until the engine pops, or runs. It will stop again.Open the choke valveStart the engine at slightly high idle rpm, and let the engine warm up a bit.Adjust the idle needle (closest to the engine, and marked "L") for best rpm, and then open it 1/4 to 1/2turn. This will be a safe rich setting to start tuning, and from here, the high speed needle can be set.High speed mixture:With the idle needle set about right, slowly apply full throttle. If the engine stays too rich, close the highneedle a bit so the rich condition is cured, but no more than that.This is the basic high speed needle setting, at which the engine will run without damage due to leanmixtures.Keep this setting while running in the engine.If the engine has run about five minutes, the plug can be checked. It should have a desert sand tan, orslightly darker. Not black, because that is an indication of an overly rich mixture, nor pale-white, becausethen the engine is too lean. This causes damage!PAGE 12 OF 22
This plug looks about right. Ondisassembly, notice the blackmixture ring in the isolatorshoulder.Plug 5 is too lean (no black ring) It also is too cold (champion DJ6J black nose)plug 6 is right mixture as shown by mixture ring, but too cold.Plug 1 is slightly lean, asindicated by the headtemperature.plug 2 is slightly richer, theblack ring still is not as high as1/4 isolator lengthplug 3 is too rich. The blackhas crept up to 1/3rd isolatorlength.plug 4 is too rich, but heatrange is OK (champion DJ7Y)The head temperatures are quite high, because measurements were made on a stationary test stand. Ina plane, with baffles installed, temperatures drop 20 - 40 degrees.Very clearly documented information from TSR:http://tsrsoftware.com/read-plugs.htmPAGE 13 OF 22
Page 1 and 2: RED LION 58ccPetrol Air Cooled Engi
Page 3 and 4: ENGINE WARRANTYThe manufacturer's w
Page 5 and 6: CDI IGNITION SYSTEMThe Red Lion ign
Page 7 and 8: The average mixture settings are 1&
Page 9 and 10: fly the model with the mixture on t
Page 11: T.M.E. 's Range of SMOKE SYSTEMS fo
Page 15 and 16: Starting from the gas tank, the fue
Page 17 and 18: intake/choke.(2) Both lowend AND hi
Page 19 and 20: Now let's check out the "float need
Page 21 and 22: the throttle will be used extensive

OPERATING INSTRUCTIONS - RC World

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?