Page:General Motors single cylinder diesel engine Model 1-53x3 installation and tests. (IA generalmotorssin00mcco).pdf/119

APPENDIX B 2.Fuel oil system

Fig.29 is a schematic diagram of the fuel system as installed.The fuel leaves the weigh tank and goes through a strainer to the main stop valve to the G.M,1-53X3. With the main stop open and fuel manifold supply valve open fuel goes to the fuel pump, then through the filter to the engine unit injector and back to the manifold via the engine spill line. With the burette stop open the fuel will also back up through the burette, out the vent, up to the level of the weigh tank.

To start a metered run it is only necessary to open the burette stop valve and then shut off the fuel tank stop. Both valves are on the manifold.

The fuel flow can then be timed from one point in the gauge glass to another. The combined cross- section of the glass and copper pipe is 1.08 sq.in. Upon completion of the timed runs it is only necessary to open the manifold valve from the supply tank. This will refill the burette while still supplying the engine. If the burette is still sufficiently full shut off the burette stop until the next run.

Fuel Burette data; The fuel measuring burette was made after considering a 5 minute student laboratory run at full power. Based on previous data the specific fuel consumption was 0.6 lbs fuel/HP-hr at a sp.gr. of 0.844 or 0.03045 lbs/cu. in. At 30 H.P. for 5/60 hour it will use .6x30x1/12 equal to 1.5 lbs of fuel; therefore, the burette was made of copper pipe 1.06 inches I.D. 80 inches long with a 60 inch sight glass, 1/2 inch I.D. This gives a total cross sectional area of 1.08 sq. in. which will give a drop of 50 inches along the sight glass for a 5 minute full power run. 48