Why Blue?

| August/September 1994

  • The After view of the 4 HP Monitor

  • The before view of the 4 HP Monitor
    The before view of the 4 HP Monitor.
  • The before view of the 4 HP Monitor

  • The After view of the 4 HP Monitor
  • The before view of the 4 HP Monitor
  • The before view of the 4 HP Monitor

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, Wisconsin.

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.


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