NEW WAY ENGINE COOLING inc. SHROUD [COWL] PLANS

New Way Motor Company being pioneers in the commercial production air cooled engines were faced with a dilemma of how to limit the metal required to ensure sufficient heat radiation away from the engines cylinders.

COOLING DESIGN:

1. Cylinder design incorporated externally a complex casting with an intricate web of holes and fins surrounding the cylinder bore to readily radiate the heat away from the explosion.
1. Design principle along the cylinder walls remained consistent across all models and types involving quite wide ribs cast at regular intervals. In addition these ribs were cast with holes to facilitate air movement for cooling.
1. Smaller models - the ribs only extended to cover the part of the cylinder exposed to combustion   
2. Larger Models - some of these had the ribs extending virtually the full length of the cylinder. Obviously to allow greater heat dissipation.
3. Apparently the casting process [SAND CASTING] used a one off sand type molding method individual to just one casting mated together as halves to form one complete cylinder. Evidence of the halved process can often be seen by inspection of an engine's cylinder fin casting, where the fin alignment of each half is slightly offset without detriment to the pour and machining of the cylinder bore.
1. Refer https://en.wikipedia.org/wiki/Sand_casting
2. New Way used a headless design for all of their engines up till the late 1920s. This meant that there was no barrier (gasket) for heat dissipation ensuring heat was readily extracted away from the engine both via the cylinder wall and the cylinder top.
1. Fin Design for the literal top of the cylinders changed with the models and whether used in horizontal or vertical orientation. Examples include:
1. Radial Finned 
2. Cross Flow fins
3. No specific change of fins as in the case of some larger engine models where the cylinder wall fins continued all the way to the top of the cylinder.
1. Applied to vertical 6 Hp Model D and some horizontal twin engines. 
2. FORCED AIR FAN - A forced air system to allow air to flow past the radiating cylinder wall and cylinder top to provide sufficient cooling for all weathers and temperature conditions.
1. Early Engine Models in both Horizontal and Vertical formats utilized a belt driven fan powered off a flywheel. 
1. Fan was shaft mounted, screwed into the cylinder wall cooling casting.
2. Lubrication was via a splash fed oil line from the crank case using a ball valve setup for fairly reliable supply.
1. Owner was expected to check its supply operation to ensure reliability by a cap at the end of the oil line.
2. Brass bush provided the bearing surface between shaft and fan housing.
3. Very early fans were driven with a round belt from a grooved flywheel and grooved fan pully
4. Later Fans of this style were driven by flat belt in a similar fashion from a flat faced flywheel.
5. A Shroud [Cowl] only encompassed the cooling casting and so was compact and confined to the cooling task.
2. Later Engine Models in the vertical format utilized a turbine fan structure (Squirrel Cage) mounted within the flywheel. A bulkier set up as it involving ducting the air from the flywheel up and over the cast cylinder cooling fin array.
1. Provided a much simpler operating process with no oil lines, valves or belts.
1. Less prone to breakdown.
2. Minimal maintenance
1. Required monitoring because the fan was very low and could become blocked with rubbish. Eg on binder engines prone to being partially choked with stalks etc.

SHROUD [COWL] PLANS

Available from the NEW WAY LIBRARY. These plans are supplied for user aware that they are supplied as an aid and a close match for some of the models specified. It is suggested that a thin cardboard template be made first to ensure that the plans suit your particular engine. Changes occurred within models, so beware.

You may find that some measurements need to be altered dependent on the thickness of material used to construct your shroud and how sharp you can make your bends. Sharp bends of course will make for greater accuracy in overall length especially where 2 x 90 degree bends are involved.

If you have an accurate shroud plan that is not listed that you want to share please email us a copy to geo.covey@gmail.com

Plans available in library or for download here:

• New Way 4.5Hp Shroud (Cowl) Model E Type C [EC]
• New Way 3.5Hp Shroud (Cowl) Model A Type C [AC] 
• New Way Jewel Horizontal 1.5Hp Shroud (Cowl) Model J Type C [JNC]
• Note may also suit some 2Hp horizontal Jewel engines (JDC)

All the Best

George