Macnaught K7/KR MINI-LUBE Series, Instruction Manual

Page: 2 / 16

KM228 Issue10 © 2017 2
TROUBLE SHOOTING GUIDE
KR GREASE GUN
K7 PUMP UNIT
The pump rod cap rises slowly
when not in use. (No visible
leak)
Grease leaks from under the
clamp nut (7).
Grease leaks from the bottom
of the strainer cover (11).
Grease leaks at the top of the
clamp nut (7).
The rod cap stays down, but
the unit will not pump grease.
The rod cap springs up and the
unit will not pump grease.
TROUBLE CAUSE REMEDY
A) Unscrew the clamp nut (7) and withdraw the assembly.
Clean the ball (28) and piston (10).
B) The piston o’ring (27) is defective or worn.
A) Dirt trapped between the inlet ball (28) and
the piston (10)
B) Replace the piston o’ring (27).
A) Air lock caused by:
i) Dent in the container
ii) Damaged follower o’ring (23).
B) Grease container empty.
C) Footvalve assembly is faulty.
A)
i) Remove dent or tilt follower (22) under the dent
ii) Replace the o’ring (23) in the follower (22)
B) Change to a new grease container or refill the old
container
C) Replace with a new footvalve assembly
B) The strainer (13) is blocked
Gland o’ring (6) and backup washer (5) are
damaged.
A) The grade of grease is too heavy A) Use NLGI No2 grease or lighter
B) Unscrew the clamp nut (7) and withdraw the assembly.
Using a screwdriver, lever off the strainer cover (11).
Clean or replace strainer(13).
Unscrew clamp nut (7) and withdraw assembly. Remove
piston (10). Carefully push against the spring (2) with the
clamp nut (7) and carefully undo the nut (29).
Replace the o’ring (6) and back up washer (5). support the
piston (10) when driving the pin (9) home. Ensure that the
flat end of the spring (2) fits in the cap (1).
O’ring (14) damaged.
Unscrew the clamp nut (7) and withdraw the assembly.
Using a screwdriver, lever off the strainer cover (11).
Replace o’ring (14)
a) Dirt under the clamp nut (7).
b) Damaged seal washer (8).
a) Undo and clean surfaces.
b) Replace seal washer (8).
TROUBLE CAUSE REMEDY
Coupler leaks. a) Dirt under the outlet ball (23) seat a) Remove the extension tube (28), spring keeper screw (21), spring (22) and
ball (23).
Note: There is nothing wrong with
the coupler itself.
Clean the seat and replace the ball, spring and spring keeper screw (part way).
Prime the pump and screw in the spring keeper screw until the grease stops
leaking. Then screw in an extra 2 full turns. Reassemble extension tube (28).
Note: If the coupler still leaks, replace the complete outlet body assembly.
When refitting the outlet body (24) hold the handle (29) in the closed position.
Enable the back-up washer and o’ring to enter squarely onto the piston.
b) The valve stem (3) is holding the
outlet ball (23) off its seat. b) Replace the piston assembly.
Gun leaks at the back
end of the piston. Glyd ring worn Replace the piston assembly.
Gun fails to deliver
grease on the high
pressure setting. a) Faulty piston. a) Replace the piston assembly.
b) Seals (25, 26) are worn. b) Replace seals (25, 26) in the outlet body.
c) Valve stem (3) has become loose
from the piston (8). c) Replace piston assembly.
Gun fails to deliver
grease on the high
volume setting. a) Dirt on the inlet valve seat (9) a) Remove control body (16), tap out the valve seat (9), o’ring (14), ball (13)
and spring (12). Clean parts and replace in the correct order.
b) Operating plunger control (10)
sticking in body (16). b) Replace the control body assembly.
Push rod in the control
body leaks O’ring (15) damaged. Remove the control body and replace worn or damaged parts.
The gun leaks at the
swivel joint. Worn seals (18, 32) Replace swivel seals.
a) Springs (2 or 4) may have
collapsed. a) Fit KR-1K overhaul kit.
b) Grade of grease is too heavy. b) Change to NLGI No 2 grease or lighter.
c) Too much compression on the
outlet spring (22). c) Reset the spring tension (Refer to A , a) in trouble shooting guide) or replace
the outlet body assembly.
When on the high
volume the gun is too
slow or hard to
operate.