Part 16  by Ramon Wilson
Part four - by Ramon Wilson

First engine assembled was the Elite Mk2 (the original was all 'self coloured' - no anodising on this one).

Hit a small problem with the piston skirt hitting what I first thought was the crank web - after taking off a mil on diameter it was catching on the top of the front housing register   a quick strip down and a step milled on cured that. The only other hiccup was the comp screw - all of these were screw cut to their respective heads to ensure a good fit but this one did not want to go in bar a few threads - it would go in the other heads okay and the others would fit but this wasn't having any of it till I ran a well opened up die down it.
Didn't take long to find the settings and once found it was away - revs kept well down at this stage - prop is the usual 'first run' wooden  12" x 5" and the fuel kept nice and rich. Couldn't run it for long as a neighbour’s house is only about 50 feet away directly behind the workshop. They are pretty tolerant but I don't like to over do it. However, with the comp well back it did have a gorgeous intermittent diesel 'crack' to the exhaust note.
The Mk3 was assembled next

The first Elite was given a quick run on assembly but it soon became apparent that the contra piston was way too loose - it seemed tight enough when pushed in but as soon as things warmed up on running you could hear it rattling. A quick strip down revealed it sitting on top of the piston and it just fell out - I guess it lapped itself in   I've mentioned this before but it's worth repeating I guess but if you overshoot the size on a cast iron piston or contra piston if it's heated a good cherry red for a couple of minutes and quenched in oil it will grow a little. This one gained a good 0.05mm but that does include the carbon!

Lapped down using two stones as before it was test fitted a couple of times to get the fit just right and it was back up for a run - and much better this time.
The second Elite exhibited a tendency to kick backwards and run in reverse - it did this intermittently when suddenly it came to an abrupt halt. A careful but anxious strip down revealed the L/H threaded rotor pin had unscrewed until the head of the screw had fouled the con rod. This was reset using some thread locker and the slight scarring on the rod removed with a needle file and a polish with ScotchBrite. No harm done so it was back up for another go.
The completed engines.


Mk 3.


2. Elite


3. Elite Mk2


4. This is the series Mk1 to the left - Mk2 to the right at the rear .....


This is the 'Stockton and Jehlik' version - a heavily modified Eta 15d full details of the modifications of which were published in Aeromodeller magazine circa 1967.

See part one here  part two  part three  part four  part five  part six  part seven  part eight 

part nine  part 10  part 11  part 12  part 13  part 14  part 15 part 16