When the engine in Bruce W. Maki's 1999
GMC Jimmy developed a connecting-rod knock, the founder of HandyManleyNess.com found himself at
a crossroads. With a book value of $3000, the sport utility vehicle (SUV) was
too valuable to scrap, but not worth the expense of a remanufactured engine.
Since buying a used engine seemed "risky", the former auto mechanic decided to
remove and rebuild the 4.3 GM V6 piston engine himself.
Engine Parts
and Engine Tools
The remanufactured crankshaft kit that
Bruce Maki bought
from a local auto parts store included all the necessary journal bearings, but
required removing the cylinder heads and pistons. So Maki purchased a piston
ring set and lower and upper gasket sets, too. Engine tools and equipment
included piston ring pliers, a piston ring compressor, an engine hoist, an
engine stand, and a flexible hone.
The
Flex-Hone for Engine Cylinders
"If new piston rings are installed,"
Maki explains, "the cylinder
walls MUST be given an appropriate scratch pattern" to promote piston-ring
seating and optimum lubrication. The "scratch pattern" that he describes is
achieved by deglazing
and plateau
finishing. By using a flexible hone, engine builders can remove the polished
surface, or glaze, from the walls of engine cylinders. They can also remove the
peaks produced by prior honing and machining operations to create a flat,
smooth cross-hatch surface.
Deglazing
and Plateau Finishing
"The best way to get the proper
scratch pattern," Bruce Maki continues, "is with an electric drill and a ball hone". First,
he chucked a 4-1/8" flex-hone into a 1/2" drill motor with a maximum speed of
850 RPM. "Many smaller (3/8") drills spin at 1200 RPM or more, which is too
fast for this procedure," the engine mechanic explained. Next, he applied some
10W-30 motor oil to the flex-hone while spinning.
Cylinder
Honing and Engine Block Cleaning
Maki then "ran the brush
up and down" each cylinder wall for one minute while running the drill at 850
RPM. "I can tell the angle of the scratch pattern by the angle of the swirls in
the oil on the cylinder wall," he later noted. With his engine honing complete,
the founder of HandyManlyNess.com finished
the job by washing the engine block with laundry detergent and hot water.
Removing any abrasive-grit
debris from cylinder walls is "very important", Maki added, to prevent "scoring"
or other engine problems.
This article originally appeared in the Flex-Hone Blog.
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