First Generation Engines
In concert with production of the overhead valve engines, Lauson also designed and produced a series of L-Head engines;
starting in around 1930. The RA was a 1/2 HP engine at 1200-2200 rpm and was built for washing machine use. These engines
were equipped with a Wico Model F magneto. The RA was also available in a battery ignition version, designated the RAB.
The RA was equipped with a suction feed carburetor.
The RA, RAU, and RAY could be equipped with a "bottle" oiler. This device provided a replenishing supply oil to the
engine crankcase. When the oil level in the crankcase fell below the mouth of the bottle, some of the oil in the bottle
would drain into the crankcase to replenish the engine oil supply.
The RA and RAU used a unique facility to pump oil into the dipper trough. With the crankcase sealed, negative pressure in
the crankcase created by the upstroke of the piston would draw oil into the dipper trough from a nozzle protruding into the
oil sump. A ball valve in the nozzle kept oil from retreating back into the oil sump. Excess oil in the
dipper trough drained back into the sump during the down stroke of the piston when positive crankcase pressure
opened a reed valve in the dipper plate.
The RA first appeared in around 1930 and was produced through the 1930's. I don't believe many of these engines
were built, because I have never seen one.
The RAU is a 3/4 HP engine at 1200-2200 rpm and was built for general purpose applications. These engines are also equipped
with a Wico F magneto. The base RAU was equipped with a suction feed carburetor, an upgraded version came equipped with
a float carburetor. The suction feed carburetor uses a spool-type throttle valve and is mounted on the crankcase in line with the governor weights.
Many RAU were sold under the Alpha DeLaval label, and were used to power cream separators as with the engine depicted on
the left. A specialized version of the RAU for DeLaval was a water cooled version with a tank cooler similar to the model VW.
The bottle oiler described above for the RA engine is clearly visible on this engine base and as is the suction feed
carburetor on the crankcase. These engines appeared around 1930 also and were built into the 1930's.
You may view the RAU in my collection by clicking Here
The RAY was a 1 HP engine at 1200-2200 rpm and was built for general purpose applications. Early versions of this engine were
equipped with a Wico FG magneto, a magneto similar to the above mentioned Wico F magneto.
This is a flywheel operated high tension magneto that resembles the Wico EK magneto. The magneto
with two sets of stationary magnets, two coils and an H-shaped rotor. The design of the rotor provides for the magnetic
field, passing through the primary and secondary coils to be interrupted at the time the points open, thus
generating the current to produce a spark. A pin on the flywheel drives the rotor; a cam on the rotor
operates the breaker points. Later versions of the RAY were equipped with
a high tension magneto actuated by magnets on the flywheel. The RAY came equipped with a float carburetor.
Many models were equipped with a flyweight governor affixed to the rear of the camshaft. The governor is enclosed in the
crankcase by a half-round cover that is equipped with a thumb-screw for adjustment. The governor has a protruding lever
that attaches to the carburetor to regulate engine speed.
The Model RAY was a popular engine for Lauson and many versions of these engines were built. Some were equipped with
rope start, some with crank start, and some with petal start. These engines first appeared around 1930 and they were
built into the early 1940's.
The engine pictured is from my personal collection. You may view other pictures of the RAYs in my collection by
clicking either Here or Here
The LA was a 1.25 HP engine at 1200-2200 rpm and was built for general purpose applications. The LA used a float feed carburetor.
Timken roller bearing main bearings were used on the LA as well as the RAY, while the smaller models used plain sleeve bearings.
A foot pedal starter was provided on all of these models, although a rope starter was optional.
You may view a picture of the LA in my collection by clicking Here
The LB replaced the LA and was rated at 2 HP at 1800 rpm to 2.5 HP at 3000 rpm.
The engine pictured is from the collection of Bart Price.
You may view a picture of the LB in my collection by clicking Here
The LBM was an air cooled inboard marine engine, built from the LB. It differs from the LB in that
it does not have a governor, is mounted on a slant for connection to the propeller shaft of a boat, and has a deep oil sump.
The engine pictured is from my personal collection. You may view other pictures of this engine by clicking Here
The LF was a water cooled inboard marine engine of 2 1/4 HP. The engine replaced the LW.
The engine was built in the 1930's. Photo courtesy of Peter Bezanson
The LFR was a water cooled engine, built like the LF but equipped with a radiator.
The LW was a small engine of 1.6 HP at 1800 RPM. It was intended mostly
for marine applications.
The LWR was a small water cooled engine of 1.6 HP at 1800 RPM. It was built with
a radiator and was intended for
stationary applications where continuous running was desired.