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Dario Brisighella Oak Creek, WI email@example.com
Root and Vandervoot Engine
Here is the latest hit or miss engine to enter my stable of model engines. This is a 5/16 inch scale of a 4 hp, tank cooled Root and Vandervoot Engine. The castings are from Rockyís Model Engines. While the originals were gasoline fueled, I elected to set up this engine to operate on Propane. The original fuel tank is rather large as it encompasses the whole of the engine base. Iím sure it would hold at least a full quart of lantern fuel.
The engine is fitted with a separate fuel pump with both a supply and return line. The fuel pump is operated by the exhaust push rod assembly. I did retain the fuel pump as for appearance alone. As the engine was water cooled it also has a belt driven centrifugal water pump. As the castings are quite hefty, I have not had to use the cooling system at this point, as the runs have been rather short.
No changes were made to the fuel mixer assembly other than open the needle valve to two full turns to run on Propane. The demand regulator was copied from one listed in the ďFameĒ Tips and Links page. Note that the copper air intake below the cylinder pipe enters the base of the engine which was the fuel tank, I think the thought here was to draw off the fumes of the gasoline into the engine. The choke is located in this intake pipe and is used to start the engine. The engine also has a rather strange exhaust system, which runs rearward from the cylinder head. No clue as to why this was done?
The original engine employed an igniter system, whereas I elected to go with spark ignition and the Hall-Effect Ignition system from MJN Fabrication. I prefer to be able to change the spark ignition point to have a smoother running engine. I did find an old photograph of a larger R&V Engine mounted on a horse drawn cart and built the cart and the wheels to replicate it. Iíve not been able to find 5/16 scale horses to complete the picture though......
Setting the governor spring has been a real challenge. I think I made at lease a half dozen different springs before I got it right. The knurled piece above the governor body adjusts the speed of the engine. I have it set now to control the top RPM at 450. It is a really sweet sounding engine at this speed.
The drawings a quite complete with the exception of identifying the required bolts, and there a lot of them. The bolts are drawn out on two sheets giving size and length etc., and are listed as part numbers. This drove me a bit crazy, until I sat down one day and marked up the drawings to listed the bolt sizes, that went with each component .
All said and done, the engine was a bit of a task as it dose have a high component count, but it certainly is a smooth runner, even sitting on the cart wheels. The wheels were fabricated from DOM (drawn over a mandrel), tubing. The spokes are threaded into the wheel hubs and silver brazed to the wheel rims.
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