Building the Prototype AMD Series Engines

The past month has seen further work on the cylinders.  Since installing my new digital readout system on the mill, I have made good progress with drilling and tapping the bolt holes in the crankcases and cylinders on all five engines.  The cylinders on the 5S and the 20IL4 are attached to the crankcase with studs and these are now all in place.

The 20IL4 cylinder has now been bored to accept the cylinder liners, although the recesses for the cooling water need to be machined too.  The bores for the singles have been roughed out in order to hold the cylinders on an arbour to machine the cooling fins and other external features.

As a reminder, I am building five prototype engines as follows, to test the design in its basic configurations:

• Engine 1.  AMD5S,  air cooled SOHC, glow ignition, lubricated by oil mixed with fuel
• Engine 2.  AMD5S, water cooled, DOHC, spark ignition, oil pump
• Engine 3.  AMD10S,  air cooled SOHC, glow ignition, lubricated by oil mixed with fuel
• Engine 4.  AMD10S, water cooled, DOHC, spark ignition, oil pump
• Engine 5.  AMD20IL4, water cooled, DOHC, ignition method TBD.

Machining the recess on the 10S.

The 5S cylinders and crankcases.

The 20IL4 crankcase and cylinder.