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Jaime Quevedo Burlingame, CA firstname.lastname@example.org 5/11/2009
I’ve been working in the Mastiff engine for quite
some time, got it to pop couple of times and then decided to dis-assemble,
clean and do some final adjustments.
Now will proceed to re-assemble and get it running again.
Engine is an L.C. Mason design from 1973.
Number of cylinders: 4
Capacity : 25cc
Bore x Stroke: 3/4" x 7/8"
Valve diameters IN/EX: 5/16”
Horizontally Opposed 4 Cylinder
Spark Ignition : ¼ “ x 32 TPI plugs
Water Cooled with pumped Lubrication
The Mastiff stands 6 ½" tall, 8 ¾" long and 7 ½" wide
Minor changes to original design made were :
Ignition, CDI with Hall effect to replace contact points.
Lubrication, fully drilled crankshaft Vs original part drilled crank, for improved lubrication.
Camshaft was built in a single piece hardened and ground Vs original independent cams fixed in a shaft with Loctite or pins.
Copyright 2006, Florida Association of Model Engineers and engine builder as noted above, All rights reserved.