Why Blue?

By Staff
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The before view of the 4 HP Monitor.
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3325 N. 65th Street Wausau, Wisconsin 54403

The before and after pictures are of a 4 HP hit and miss Monitor
gasoline engine made by Baker Manufacturing Company of Evansville,

I have always admired the styling of the Monitor upright engine.
I believe it is an excellent example of form and function, a form
of sculpture. It is one of the few engines that can be recognized
at a distance of 100 yards the cast iron ball hopper, ball shaped
muffler and cast iron cylindrical gas tank with the Monitor logo
being the cardinal features. The builders of the Monitor surely
could have built the engine with simpler castings or parts, but
they didn’t, and it makes all the difference.

The engine was complete when I received it, but in need of some
TLC. Some of the things I immediately noticed were that the piston
was seized in the bore, and there were nearly two feet of frost
cracks in the water jacket. The loosening of the piston went easy.
I removed the spark plug, poured in some penetrating oil, let it
sit for a few days. Then I took the rod off the crankshaft and
bounced the crank against the connecting rod and the piston came
loose. Next I did the usual valve job and timing of the ignition
and exhaust valve. The engine started without much trouble. I like
to run an engine before starting restoration to check to see how
true the flywheels run (a wobbly flywheel may indicate a bent
crankshaft or flywheel) and to get a better indication of the
overall condition of the engine. The engine did not have much
compression. I figured it had a stuck ring or two. I should note at
this time I had not had the head off the engine. The engine has
pocket valves which can be ground without taking the head off.
Anyway it was time to start restoration. I took the hopper off and
then the cylinder head. It became immediately apparent why the
compression was low. The bore was severely scored due to one of the
pins in the ring land, used to keep the rings from rotating had
backed out, damaging the bore. The repair was to bore the cylinder
75-thousands of an inch over size and braze the piston and turn it
to fit the oversize bore. All the governor and valve gear pivot
points were repinned.

The repairing of the cracks in the water jacket was a challenge.
I tried the cold process of welding with no success. The next thing
was to try the hot process. To do this, I had to preheat the
cylinder. But such a large casting required a large amount of heat.
To do this my friend Ralph built a large propane torch, capable of
a 4 inch by 18 inch flame. The crack repair process I used is as
follows: First, I drill ? holes at the ends of the cracks. Second,
I Vee out the cracks. Third, I heat the casting to red hot. I am
now ready to weld. I use nickel rod and an arc welder, using short
beads and peaming the weld immediately. Reheating of the weld and
casting during repair is done to relieve stress. Upon finishing,
the casting is buried in ash for slow, even cooling.

The rest of the restoration was pretty much straight forward.
The woodwork is white ash. The blue color match is Dupont 4191A
Balboa blue and the gray is Dupont 538A.

And now why is the engine blue and gray instead of the usual red
or all gray? Well, during the sandblasting process I came across
traces of blue on the valve gear, crankcase cover, flywheels and
fuel tank. Now, I normally would have disregarded this blue paint
as another coat of post production painting like the black paint
over the original gray on the rest of the engine, because I had
never seen or heard of blue being used on Monitors. But one of the
letters from Baker Manufacturing Company that Ray Ehlinger sent me
specifically mention gray and blue engines. This information, of
course, verified my conclusions.

I had written to Reflections for information on the Monitor. I
would like to thank John Vialard for the detailed drawing of the
woodwork and Ray Ehlinger for the copies of the letters from Baker
Manufacturing Company.

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