[Vwdiesel] Making a 1.6 VW diesel into a 0.8 L twin for small genset

[Area31 Research Facility]

In the search for small water cooled and relatively quiet running diesel
engines for genset use, and having successfully built a full sized 10 kW
plant based on a 1.5 L, NA 1980 VW Rabbit diesel I am looking for
alternatives when somewhat less power is needed.  It makes sense to start up
a smaller plant and run it at about 75% load to get maximum fuel efficiency
rather than lightly load the 10 kW plant where efficiency drops and fuel use
does not drop proportionately to load, remaining near high electrical output
levels.

There are single cylinder diesel engines available which fill the bill but
are often expensive if purchased new, or are very hard to find as in the
case of the discontinued classic and sought after Lister CS (cold start)
singles, those engines with enormous 24" flywheels on each side of a single
cylinder that putt-putt-putt along at 650 RPM and will do it for years
without major maintenance.  When I can find a pair of those that I can
afford my search will be over. In the meantime I am looking at affordable
alternatives to a DIY'er with a machine shop at his avail, but next to no
cash.

Earlier this summer I stumbled across an ancient 810 cc, Petter PJ-1, 10 HP
@ 1800 RPM British made lighting plant with a single cylinder air cooled
diesel engine and an enormously massive flywheel on an alternator in direct
drive mode that looks large enough to make 10 kW.  At 2 HP per kW rule of
thumb this plant therefore should make 5 kW.  The plant was almost rusted to
dust and the engine solidly siezed but I got a very good price on it and
grabbed it happily recognizing it's potential. After working on it's
restoration all summer I now have it running and it can actually make almost
6 kW when pushed into the black smoke realm.  At 5 kW the exhaust is clear
(except for some oil smoke issues that I am now sorting out which I believe
to be mainly from a leaking exhaust valve guide).

To my horror I have discovered that this direct injection diesel is so loud
that It will be difficult for me to use it as proposed (within 100 miles of
civilization).  The fact that it is an air cooled engine was not a choice
when I got this and I will shy away from purchgasing any more air cooled
diesels for the elevated noise factor as well as the difficulty in engine
temperature control at low load situations (runs too cool to lubricate
properly) and cannot pipe waste heat elsewhere where it could be used like
for making domestic hot water.

So, while I dink with my Pitter Petter, even seeing how it works at 900 RPM
instead of 1800, where the noise output drops from 140 dBA to perhaps 130
dBA, my search continues for a practical slow speed water cooled diesel
engine that 'can run on the fumes of an oil soaked rag'.  The idea of
removing pistons from a VW diesel engine has come to mind.  I haven't
studied the firing order or crank throws yet, but assuming that they
accommodate this from a physical balance and even firing perspective I was
thinking of disabling #1 and #3. This is easily enough done.  Yank the
pistons and con rods out and remove the lifters so that the effected
cylinder valves cannot open or touch the camshaft.  What does one do however
with the two unused FI pump outputs?  Can they be capped tight for zero flow
and not suffer pump damage?

Your thoughts welcomed.

Rob