National Transit 2-Cycle Vertical
Hot Tube Engine Project

(Circa 1900-1910)


 This was a "mystery" engine I bought off the net which turned out to actually be a National Transit. It was missing the hot tube and generally pretty rough. When I got it home, I opened the crankcase to find a bunch of wooden wedges used by someone to "unstick" the piston. No wonder the crank would not turn ! This one was gray, but under the thick gray paint was black and red. The bearings inside were shot. Needed to make new bronze lower con rod bearing as well as rebushing the bronze in the piston. Oh well, a call to MSC sent the bearing blanks to save me hogging them out of solid bronze. Even the hole for the wrist pin in the rod was sloppy and needed a steel bushing.

Here is another National Transit type VT-13 that I am working on. This one is missing the head, stuck but worth saving.If you run into one of these for sale or see a head, please let me know. Mine has 2 flywheels. This model could be equipped with a Wico L1, Hot tube or igniter (shown). A very sturdy engine when compared to its earlier brother I restored.

IS'S ALIVE !!! 3/26/99 and all finished. I ran it for the first time today in who knows how long for about 5 minutes. I had some trouble getting the mixture right and the oilers were slobbering because the checks were not working...details. What a nice sounding engine ! Runs at about 120-150 rpm. My wife remarked how different it sounds since it is a 2-cycle. My guess on the water pump belt ratio resulted in a nice steady flow.


End-on shot (right) showing the water pump drive and pretty brasswork. I made the accumulator from a 24 inch piece of 3" diameter brass tubing. Copper ends were made and soldered on. The whole thing was buffed and laquered. All the copper tubing was standard 1/2 house plumbing which was sweat fitted. Got to try out my clipper belt lacer for the first time too to splice an old piece of leather belting I had for the pump. The pump is a bronze Oberdorfer (my favorite pumps) which is of the gear type. Now that it is done, I really like the lines of this engine. The hot tube and burner assembly (which I made) worked great.

Took the engine to a local show and with the chimney pictured and a 5 inch hot tune; it knocked. Took the engine to Coolspring this year (2000) and replaced the 5" hot tube with a 3" tube. Still knocked. I ended up putting a Myrick burner chimney on it since I could adjust it to heat the top inch of the tube. Today, July 4, 2000, I started it up and it appears to have done the trick, no knocks. By tightening up on the nut on the bottom of the flapper valve, which is connected to the governer, it limits the fuel admitted in relation to the rpms. It is kind of a bastard between hit'n'miss and throttle governing.
Check out the cool plate I got from a fellow engine buff at Coolspring on the left.


 An older National Transit found at Coolspring Museum. This one shares several parts with mine and has a crosshead. This one is from 1896-1900 according to one of the museum directors.

National Transit Lil'Hummer vertical air-cooled engine also at Coolspring. The exhaust draws air in from the bottom of the cylinder to keep it cool. This engine stands about 3 feet tall. Hot tube ignition is evident on the right of the cylinder.