TM 9-4910-679-14&P
VALVE SEAT GRINDING EQUIPMENT
CAUTION: Accessories for your Valve Reconditioning Equipment are described in this manual. The use of any other
accessory might be hazardous.
DRIVERS-In Drivers,
the spindle incorporates a positive vibrat-
ing action, which lifts the grinding stone
from the seat once each revolution. This
prevents loading the stone, speeds up
grinding and reduces stone wear. All
grinding is concentric, cutting the entire
circumference of the seat and ensuring cor-
rect alinement.
The Heavy- Duty Driver maintains high grinding speed with a large, complete range of seat grinding stones.
All Drivers have an instant-release trigger switch for safety. The switch, however, may be locked in the on position by
depressing the Switch Locking Button while the trigger switch is on and releasing the trigger before releasing the locking
button.
PILOTS--
GRUV-TOP Self-Centering
Pilots provide an accurate.
rigid axis for grinding with
Stones. Two
machined tapers-at the top of
the shank, to fit the top of the
valve guide, and at the bot-
tom, to expand a split sleeve
in the lower end of the guide.
The expanding feature com-
pensates for worn guides and
eliminates a large stock of
oversize pilots, as Self-Center-
ing Pilots expand 0.020" to
0.030".
The patented GRUV-TOP
feature locks the retainer ball
in the Ball-Bearing Stone
Sleeve, holding the inner
sleeve stationary and prevent-
sleeve and pilot stem. These
Pilots also fit Standard Stone
Sleeves.
To select the proper size pilot refer to the booklet "'VALVE STONE AND PILOT HANDBOOK" Form 1094.GRUV-
TOP plug type automotive pilots are available. These pilots tilt the valve guide opening and do not expand since
there is little or no wear upon surfaces in these openings.
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