REO Grand

By Staff
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Model 552A REO engines such as this one belonging to Donald
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Kinsey’s grandson were originally used to power reel-type mowers.
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Model descriptions of popular REO gas engines of the late 1940s and early 1950s. (Courtesy of Doug’s REO Engine Site at:

I first came into contact with the little REO
engine sometime in the early 1960s, and quite by accident. I don’t
recall the precise incident or point of acquisition of this little
jewel of a design, but because of its nearly indestructible
qualities, I have managed to keep it running on demand for over 35
years. The only maintenance necessary was to change the oil and
install a new spark plug. It always started in the spring, after
sitting in the barn for over six months, ready for the next

The particular engine I’m talking about is a Model 404, Type E2.
My information indicates that it was manufactured in 1951 and is
rated at 1-1/4 HP and was used on a reel-type mower called the
Runabout Model WE-18.

It has done yoeman service, with its first application being a
go-kart for the kids. The go-kart had a bed rail frame, a front
axle from a Bolens lawn tractor, a rear axle from a Sears &
Roebuck reel-type mower and a steering gearbox from an old washing
machine transmission. I will never forget how the kids would rev up
that little engine while they were running around the yard. I was
sure it was going to come unglued, but it didn’t! Later on, I put
the engine to various other uses, with the latest application being
to power the furnace fan I use as my “air-conditioner” for the
shows in Michigan.

Assuming I had sorely neglected this little jewel of a
powerhouse after 35 years of various kinds of use and abuse (it was
smoking a little and fouling out), I decided to tear it down to see
what work it needed. I removed the head, the output shaft housing
and the crankcase. It was carboned up somewhat, and the valves and
seats needed refacing, but to my surprise, there was very little
wear to the cylinder. The piston had some side play, and the output
shaft seal and bushing need replacing. The crankshaft and camshaft
gears showed minimal wear and were in excellent condition. I’ll
install new rings once I’ve tended to everything else. Then the
little unit will be put back in service, hopefully for another 35
years. It is surprising what a little engine with a 2-inch bore and
the heart of a lion can do!

Shown is my grandson Kristopher Kinsey’s Model 552A REO, which
was used on Model WD-21 Royale reel-type mowers in 1949-50. All REO
engines are quite similar, and the model and serial number is
specified on the nameplate.

REO Overview

REO, which stands for Ransom Eli Olds, was located in Lansing,
Mich. Olds was involved in many enterprises including cars, trucks,
engines and various types of lawnmowers. The little REO was
manufactured from 1949 through 1958 and was produced in over 20
models with horsepower ratings including 1-1/4, 1-1/2, 1-3/4 and
2-1/4. They were used on reel mowers, rotary mowers and snow
throwers. They also had an application for small boats called the
Trollabout. The REO mower engine was mounted on a platform in the
boat and shafted through the bottom of the boat to the propeller. A
simple, inexpensive inboard-outboard! In my travels I have only
seen one unit of this type, and one may conclude it was not very
popular. Also, this configuration would, I believe, be rather

These engines are certainly unique in design. The cylinder is
slanted at a 45-degree angle and the flywheel runs contrary to the
conventional rotation. Power is taken off the camshaft, which means
the final drive pulley runs in the “right direction.” Another
feature is the camshaft. It has only one lobe, which operates both
valves through a unique system of little levers set at critical
angles to provide the proper valve timing. The entire engine was
compact, reliable and seemingly indestructible. I can vouch for
this from my experience with the Model 404 that I have.

Contact engine enthusiast Donald Kinsey at: 10267 Tyler Road,
Lakeview, MI 48850; (231) 972-4613.

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