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3W 157xi B2 / TS / CS Engine Manual

more infos: www.3w-modellmotoren.de

tray. Fuel tanks, batteries, and other equipment can be mounted on top of this tray; the canister(s)

being installed below it. Close off the lower compartment at its rear with an angled former. Locate

this former 1" behind the back of the canister(s). Next cut a hole in the bottom of the fuselage just

under the rear of the canister(s). In this way the air coming from the front of the model can flow

over the canister(s) and then be deflected by the angled former so as to exit through the hole in

the fuselage. Do not forget to reinforce around this hole.

Important:

This exit area needs to be four times (4x) as large as the intake area.

Propellers

 Only use propeller brands and sizes that are approved for your engine

 The propeller blades must be of the same length

 The propeller must be flat (You can check for flatness by putting the propeller on a level

surface. The maximum difference of the blade heights 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 must drill the propeller from the rear.

 A drill guide is recommended, but the propeller washer can be used as a drill template. (Fix

the propeller washer onto the propeller in the center-bore using a bolt and nut. Drill one

hole; put one of the propeller bolts into the hole. Continue until the last bolt is used.)

 If you cannot hand tighten all of your prop bolts easily then you have not drilled the propeller

correctly. This can lead to sheared propeller bolts.

 Balancing your propeller is absolutely critical to the health of your engine. You must keep

your propeller balanced. (Propeller balancers are available from DUBRO, and others.)

 Always remember that when the engine is running every person must stay behind the line

of the rotating propeller; never to the side or the front!

Carburetor settings

Before each engine is shipped it has to pass QC and is then test run. We do a basic adjustment

of the carburetor needles at that point.

highspeed needle H:

   3/4

Summary of Contents for 157xi B2

Page 1: ...ENGINE MANUAL 3W 157xi B2 TS CS www 3w modellmotoren com ...

Page 2: ...s been designing two and four stroke engines for gasoline and diesel for 38 years We are continually looking at new technologies and working on new designs Please be assured that we at 3W always strive to provide you with engines that are state of the art You can count on your 3W engine to have a high level of precision high torque in the low rpm range excellent running characteristics a long life...

Page 3: ...ny direct at your costs The garantee is limited to the value of the product The guarantee does not cover any damage caused by misuse or neglect accidents abrasion exposure to extreme temperatures solvents acids water normal wear and tear or damage by common carrier Warning This engine is not a toy Serious injury and or death can occur from its misuse READ and become familiar with this entire instr...

Page 4: ...e adequate 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 hand to start your model Adjust your carburetor correctly Not adjust your carburetor while the engine is running Insure that your spark plug is in good condition and is secured correctly Insure tha...

Page 5: ...r engines 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 ensure a tension free mounting of the engine The surface that the engine is mounted on must be on an even plane i e a flat and level surface so that there is no strain on the engine itself Again th...

Page 6: ...er 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 in...

Page 7: ...ings 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 piston or pistons Following the instructions and recommendations in this manual will keep the engine operating comfortably within the normal temperature range Rear induction Carburetors whether front or rear require a steady supply of f...

Page 8: ...ll malfunction 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 coordination of the sensor s to the magnets Refer to our special ignition description for further information Canister mufflers To prevent damage to the header s a flexible support bracket is req...

Page 9: ...de heights 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 must drill the propeller from the rear A drill guide is recommended but the propeller washer can be used as a drill template Fix the propeller washer onto the propeller in the center bore using ...

Page 10: ...achine 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 with a plastic ball joint or plastic clevis at each end This will keep your RPM much more consistent and accurate around idle where it really counts Engine Break In Use a 2 stroke petroleum based...

Page 11: ...n Note For break in a smaller propeller is recommended Important Remember that when the engine running ever person must stay behind the line of the rotating propeller never to the side or 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 3W 2 stroke o...

Page 12: ...r throttle servo A high quality throttle servo is recommended for reliable and accurate operation of the carburetor Never fill the fuel tank via the carburetor fuel line Use the same I D for tank ventilation and the carburetor fuel line Use small plastic cable ties on all fuel line to fitting connections We recommend cutting the fuel line in the fuel tank in half And then joining them back togethe...

Page 13: ...er tune the carburetor whilst engine is running Stop the engine Tune the carburetor and start the engine again Repeat this procedure until the carburetor is properly tuned Make sure that no gasoline will be splashed into the hot muffler s Only 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 Importan...

Page 14: ...ts and stops quickly Wait for the propeller to stop spinning turn off the ignition and open the choke s Switch the ignition back on Flip the propeller again until the engine starts Warm up the engine for at least 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 recomm...

Page 15: ...ust your carburetor from there This problem may also indicate a dirty carburetor or faulty ignition The engine runs rough and 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 sure it is rigid Check to make sure the engine is mounted on a level surfac...

Page 16: ...7500 min 1 rpm Weight Poids 3930 g 8 66 Ibs incl ignition Weight Poids TS 4105 g 9 05 lbs insl ignition Crankshaft 3 Ball bearings 3 Roulement à billes Pleuel Connection rod Bielle Needle bearings on both ends Roulement à aiguille aux deux cotés Benzin Gasoline Version 1 50 1 80 Mix full syntethic oil high Octane unleaded fuel 98 Octane is recommended IIS Zündung IIS Ignition V cc allumage 6 0 V N...

Page 17: ...3W 157xi B2 TS CS Engine Manual more infos www 3w modellmotoren de mounting bolt pattern ATTENTION this drawing is in 1 1 size disable any Acrobat print setting to fit it into paper size ...

Page 18: ...ent consumption depends on the voltage of battery used with increasing voltage current consumption goes down Like all other electronic devices the ignition box gets warm under operating conditions For that reason a simple airflow has to be guaranteed Therefore the 4 delivered rubber mounts have to be used for installation insuring a one millimetre gap underneath the box Cable information Sensor ca...

Page 19: ...t car votre droit de garantie en cas de réclamation n est valade que sur présentation de ce document Cette garantie est valable seulement si accompagnée d une preuve d achat Facture du revendeur Condizioni di garanzia Riconosciamo una garanzia di 36 mesi dalla date di acquisto Questa garanzia si limita esclusivamente alla sostituzi one gratuita dei pezzi difettosi la cui causa è da imputare a dife...

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