TM 3-6665-302-34
(9) Raise and secure M74 test set flow rate
(5) Turn VOLTAGE ADJUST control fully
clockwise.
meter bracket in vertical position.
(6) Obtain an operative pump assembly.
(10) Insert M43 detector unit flow rate met-
(7) Connect M74 test set VACUUM TEST
tubing to the air inlet port (2, fig. 3-19) of the
er into M74 test set port (turn clockwise).
pump assembly.
(11 ) Perform procedures in the flow rate
(8) Connect PUMP POWER cable to the
meter troubleshooting chart (fig. 3-14).
pump assembly connector.
Section Ill. M43 DETECTOR UNIT BOTTOM CASE ASSEMBLY (1A1)
3-6. General
Direct support maintenance personnel are au-
thorized to replace the M43 detector unit bottom
a. Removal.
case assembly or repair it by replacing the seal,
(1) Release four clamping catches (10) and
catches, and instruction plate.
remove bottom case assembly (2).
(2) Raise latch of catch (10) and remove
3-7. Removal
two screws (8) and lockwashers (9).
Release four catches (10, fig. 3-16) and separate
detector unit assembly (1) from bottom case
b. Installation.
assembly (2).
(1) Aline clamping catch over screw-insert
holes in bottom case (4). Then attach two lock-
3-8. Installation
washers (9) and screws (8). Tighten screws.
Check that seal (3) is correctly seated in groove
(2) Assembly bottom case assembly (2) to
around the top of the bottom case assembly.
detector unit assembly (1) and secure four cat-
Assemble detector unit assembly (1) to the bot-
ches (10).
tom case (4) and secure four catches (10).
3-9. Seal
a. Removal.
a. Removal. Remove two screws (7). Remove
(1) Release four catches (10, fig. 3-16)
bottom catch (6) from bottom case (4).
and remove bottom case assembly (2).
b. Installation. Aline bottom catch (6) over
(2) Using a blunt tool, such as a screw-
screw-insert holes in bottom case (4). Then at-
driver, pry seal (3) from groove in bottom case
tach and tighten screws (7).
(4) and scrape adhesive from groove.
b. Installation.
(1) Coat groove in bottom case with sili-
NOTE
cone rubber adhesive (item 8, table 1-1).
Do not remove old instruction plate (5,
(2) Insert new seal (3) into groove and
press firmly.
a. Roughen surface of old instruction plate
(3) Wipe excess adhesive from surface of
(5) and wipe surface with dry-cleaning solvent
seal.
to remove loose scale, grime, or grease.
(4) Cure adhesive according to manufac-
b. Remove protective backing from new in-
turer's instructions on the adhesive container.
struction plate so that adhesive is exposed.
(5) Assemble bottom case assembly (2) to
detector unit assembly (1) and secure four
c. Position new instruction plate (5) over old
catches (10) .
instruction plate and press firmly in place.
Section IV. DETECTOR UNIT ASSEMBLY (1A2)
bly by replacing a gasket on the rainshield as-
3-13. General
sembly, a gasket on the flow rate meter, the
Direct support maintenance personnel are au-
thorized to repair the M43 detector unit assem-
hande and its attaching parts, the hand crank,
