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3W 85i Engine Manual

more infos: www.3w-modellmotoren.de

 

It is strictly prohibited:

To mount the engine directly onto spacers for the following reasons:

a. If the spacers are too long and/or not stiff enough the engine could vibrate leading

to the crankshaft starting to twist, further leading to the crank case being destroyed.

b. If spacers are used to adjust the side and/or down thrust and this spacing no longer

provides an even plane (i.e., a flat and level surface) the crank case will be distorted,

leading to the crankshaft starting to twist, further leading to the crank case being

destroyed.

 To mount the engine directly onto a large (wide) former or firewall for the following reason:

a. If the cylinder(s) is/are too close to this wide former or firewall, the floating air cannot

pass freely over and then away from the cylinder(s). Cavitating hot air can/will overheat

the engine.

Engine Cooling

A proper cooling system is vital for any engine. An air cooled engine requires an appropriately

sized air intake. Also to keep this air cooling process working the incoming air must be exhausted.

Further, the exhaust air outlet should be four times (4X) the size of the cool air intake.

Example:

 10 square inches of air intake area would require

 40 square inches of exhaust air outlet area

It is up to you to insure that the air flows freely to, over, and away from, the hot cylinder(s) and

muffler(s). Please refer to Engine Installation for motor box considerations, and to the following

tips on baffling.

Baffling

Deflecting of the air (baffling) to and over the cylinder(s) is highly recommended for engine cooling.

The idea is to get all of the cool air that is coming through the air intake opening(s) to hit the middle

of the cylinder(s) directly, and then be forced over the cylinder(s), creating turbulent air moving

Summary of Contents for 78B2

Page 1: ...ENGINE MANUAL 3W 85i B2 www 3w modellmotoren com...

Page 2: ...wer And a 36 month conditional warranty We wish you plenty of fun and success with your new 3W engine Sincerely The 3W Team Limited Warranty We grant a 36 month warranty from the date of purchase This...

Page 3: ...uate filtering of your fuel Maintain your engine properly keeping it clean etc Use a pre flight check list before flying your model Secure your model properly when starting Not use your fingers or han...

Page 4: ...nes up to 106cc or 3 8 aircraft plywood for engines in the 150cc class For builders experienced with making composite motor boxes a comparable strength should be attained It is absolutely vital to ens...

Page 5: ...then away from the cylinder s Cavitating hot air can will overheat the engine Engine Cooling A proper cooling system is vital for any engine An air cooled engine requires an appropriately sized air in...

Page 6: ...ated condition where sealed ball bearings and needle bearings could be damaged Further you risk an elongation of the heated engine parts and or having an oil film build up which could lead to a seized...

Page 7: ...unction e g backfiring or shutting down Ignition details The red cable is positive The ignition timing has been set at our factory When fitting a new ignition it is important to achieve the correct co...

Page 8: ...hts should be no more than 1 64 The propeller tips must have an identical shape This is especially important when using 3 or 4 blade propellers You must use a drill press to drill your propeller You m...

Page 9: ...screw and nut Then solder the arm in place Refer to the attached illustration Note The use of a soft pushrod for the throttle plastic or nyrod is not recommended Use a metal or carbon fiber pushrod wi...

Page 10: ...r the front After Initial Break In Use high grade fully synthetic 2 stroke oil Use the oil manufacturer s recommended gas to oil mixture Use a high Octane unleaded fuel 98 Octane is recommended We use...

Page 11: ...fuel line in the fuel tank in half And then joining them back together with a brass tube The brass tube prevents a folding of the fuel line with could cut the fuel supply for the engine see tank phot...

Page 12: ...nly 3W mufflers or mufflers authorized by 3W with an acceptance test number should be used Only 3W ignition systems should be used for proper operation Important Using unauthorized products or failing...

Page 13: ...20 seconds Due to the high power and torque of the engine s it is not recommended to open the throttle abruptly Precision tuning of the carburetor The use of a tachometer is highly recommended And aga...

Page 14: ...d is vibrating strongly Balance the propeller Check the ignition timing Check your plumbing for air fuel leaks Check your spark plug for carbon and check the spark plug gap Check the motor mount to be...

Page 15: ...d range Vitesse de rotation 1200 8000 min 1 rpm Weight Poids 2880g 6 05 Ibs incl ignition Crankshaft 3 Ball bearings 3 Roulement billes Pleuel Connection rod Bielle Needle bearings on both ends Roulem...

Page 16: ...20 kV Rpm max 12 000 rpm 12 000 rpm Magnet red north pole upper dead point upper dead point Magnet green south pole 55 o before upper dead point 55 o before upper dead point Like all other electronic...

Page 17: ...t car votre droit de garantie en cas de r clamation n est valade que sur pr sentation de ce document Cette garantie est valable seulement si accompagn e d une preuve d achat Facture du revendeur Condi...

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