PHQ250JHMAVL Jackleg MK 1 Parts and Repair Manual PDF

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54. Once the valve plug (A744) is loosened remove the
valve plug from the valve box (A745). Next remove the
valve (C1648) from the valve box (A745). Wash all the
valve parts in Varsol and blow dry. Check that the parts
are clean and free from debris. Check for sharp edges on
the components caused by long use. Sharp edges cause
the drill to run erratically and should be removed with
emery cloth. Take care to just remove the sharp edge.
55. Align the valve properly on the stem of the valve plug. Push to mate with the face of the plug.
Cover the two holes in the large diameter of the valve plug with your fingers. Pull the valve away
from the mating surface. If it moves easily there is no suction created and the valve is worn.
56. Reassemble the valve and holding the assembly firmly in both
hands shake back and forth. Listen for a clicking noise that signifies
the automatic valve is moving inside the valve. If no distinct clicking
is heard the valve is jamming. The valve must be disassembled to
find the cause before returning it to the drill. The valve surfaces are
precision ground to within thousands of an inch so never hand grind
the faces of the automatic valve or the inner faces of the valve box.
Cylinder Lug Bushing Removal
57. Examine the cylinder lug bushings (C1523) for
sign of wear. The three large O-rings (164231) often
wear into the inside diameter of the bushing and can
cause air crossover leaking.
To remove the cylinder lug bushing turn the cylinder
on its side in the chain vice. Insert service tool T225
into the bore of the bushing and strike repeatedly
with a hammer until the bushing drops through the
cylinder boss.
58. To insert a new cylinder lug
bushing (C1523) turn the
cylinder over in the chain vice,
align the locating flats on the
new bushing with flats on the
cylinder lug. Drive home the
new bushing until it seats using
the T225 lug bushing punch.
Version 200711