3.8 H.P. Coborn C3 aircooled engine
- s/n 20034 & Iron Horse genset.
8th August 2009.
Update 9th August 2009. Following mail
to the S.E.L. and Oldengine lists I have established that the "compressor"
I mentioned below is actually a "vacuum pump" as used in a farm dairy on
"milking machines". This makes sense and would account for the lack
of safety "blow-off valves" and the like. From another source I ascertained
that production of these engines ceased in 1963 and that the usual colour
was red. This colour ties up with the photograph in David Edgington's book.
Update 10th August 2009. THE COBORN LIVES !! Today I made a crank handle for the Coborn and cobbled together a spring loaded "throttle control" (which was missing on the engine), squirted some oil in through the spark plug hole to lubricate the rings (and gave it a few turns to distribute this oil) checked oil and added some petrol - all the connections on the fuel line leaked but that's a small problem to rectify. It also needed a new "lug" on the magneto wire. After a few tugs of the crank (it's got an impulse magneto so you do not swing it) it burst into life but raced. Quick shutdown - fiddle with the throttle control and choke (I had to tie this down with a piece of wire) and tried again. After a little more fiddling with the spring on the throttle control it settled down and ran beautifully. I'm a "Happy Chappy" the engine runs beautifully and I ran it for about an hour - it never missed a beat but does seem to be a bit of a "Gas Guzzler" but this will get better with a bit of tweaking.
Here is a short (21 seconds) video of it running (5.5 Mbytes .wmv).
I came across this British
made aircooled Coborn engine on a trip to the Karoo about 9 or 10 months ago
and a deal was struck for it as well as the Johnson "Iron Horse" pictured.
Unfortunately, at the time, the truck we were in was full (of engines) and
these two had to be left behind for another trip. Well my friends Rod Burnett
and Neville Botha have just made another trip to that area and brought the
engines back for me.
According to David Edgington's
excellent book "Old Stationary Engines" (latest edition
available here) the aircooled Coborn engine was produced from the early
1930's, first by "Kryn & Lahy Ltd." and then by "Browett Lindley Ltd."
and later by "K & L Steelfounders and Engineers" (all British companies).
These companies were all members of the "600 Group" of companies. My engine
was produced by "Browett
Lindley Ltd." as stated on the rather large etched brass
plate mounted on the air cowling of the engine.
Of particular interest to
me was the fact that David listed this engine under the heading of
"Lesser known manufacturers". In my book that translates to "collectible"!
I have been unable to determine
a date for when these engines went out of production but assume (without any
proof) that it was probably sometime in the 1960's so I, again, assume that
mine was probably manufactured in the 1950's sometime. I would appreciate any information in this regard. (See
The information that I have
been able to glean from the "Spec. plate" is
Model : C3
RPM : 2000.
(See update above.) What is of interest is the compressor (now known to be a vacuum pump) that it is driving (via a flat belt). This is obviously a later "owner addition" as there are no safety features ("blow - off" valve or similar) and the general construction appears amateurish (or small town engineering shop perhaps), there is not even a connection for an air hose (but this could be easily added) only a brass tap to allow the comressed air to escape. The anodised aluminium plate points to it being not too old but isn't that curved spoke flywheel pretty !!
The compressor does have
an aluminium spec. plate but very little is readeable on it - From what I
can read the language appears to be either Dutch or German
List members, can anyone identify the vacuum pump for me ?
information will be appreciated.
The Iron Horse is a little
rusty but also appears to be virtually complete and is loose so should also
be a very easy restoration !
The original trip also netted me a small aircooled Vincent engine, an aircooled J.A.P. and the remains of a Maytag twin "Homepower" genset so, all in all, it was a pretty successful trip for me.
Click on any pic to
see a larger version - use your "back" button to return
The aircooled Coborn driving an unknown vacuum
pump by means of a flat belt.
The Coborn Engine showing the carburettor
and Wico Type A magneto.
The Coborn Engine showing the fuel tank side.
A view from the back of the Coborn. The cover plate
with the holes houses the governor baffle which is activated
by the volume of air passing over the cylinder head from the
finned flywheel - a system seen on many "Briggs & Stratton"
and other aircooled engines.
The vacuum pump of unknown origin - from the remains of
text on the anodised plate on the crankcase access cover
it appears to be of German or Dutch origin.
The other side of the vacuum pump.
Johnson's Iron Horse - rusty but complete and loose.
It even has compression.
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