UNIT MAINTENANCE INSTRUCTIONS FOR THE
READY/AVAILABLE IF:
If weapon has been stored and not used for a period of 90 days, perform PMCS.
Visually inspect exterior for rust. Remove rust with lubricant and wiping rag.
Weapons with less than, or up to, one-third of the exterior protective finish missing will be touched up with solid film lubricant.
Weapons exterior has more than one-third protective finish missing.
0039 00-2
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) – Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun - Continued
ITEM
NO. INTERVAL MAN
HOURS ITEM TO BE CHECKED
OR SERVICED
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
1 L K 0 0 4
MK19 Mod 3
1 L K 0 0 5
MK19 Mod 3 (UGWS)
TM 9-1010-230-23&P 0039 00
0039 00-3
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun - Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
2 Bore and
Chamber
WARNING WARNING WARNING WARNING
Appropriate eye protection is recommended when cleaning the weapon and/or its parts.
NOTE NOTE NOTE NOTE
If possible, clean bore and chamber immediately after firing.
Soak borebrush (on a cleaning rod) with Rifle Bore Cleaner (RBC). Insert borebrush into the muzzle and chamber.
Resoak the brush. Repeat until bore and chamber are clean. Carbon may be removed from the chamber using abrasive cloth. Wipe bore and chamber dry and apply a light coat of lubricant.
Bore and/or chamber has carbon buildup (caked on carbon).
1 L K 0 6 9
0039 00-4
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) – Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
3 Feed Throat
(MK19 Mod 3 only)
1. Check plungers for condition of the following components: weak springs;
knurled pins (test by squeezing each set together).
Plungers do not firmly secure the feed throat.
Springs are weak or pin is missing or broken.
2. Feed throat (check for cracks and bent areas). If bent, install on gun's receiver. Perform dummy round function test (see item 13).
Dummy (round) does not pass through the feed throat.
3. Check for and remove rust with an abrasive cloth.
Preserve with light coat of lubricant.
Interior of feed throat is rusted.
1 L K 0 7 0
4 Top Cover
Assembly 1. Raise the top cover.
Ensure the handle is not loose, dry, or binding.
Ensure spring is not broken.
The lock handle and spring do not move as a unit with no relative movement between them.
Spring is broken.
2. Separate the secondary
drive lever from the top cover (WP 0043 00).
Remove any rust with wiping rag and lubricant.
Lubricate lightly.
Rust is present in the pivot post hole.
TM 9-1010-230-23&P 0039 00
0039 00-5
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
5 Secondary
Drive Lever Assembly
Inspect for burrs. Remove with a stone. Verify the presence of the retaining ring on pivot post.
Retaining ring is worn or missing.
6 Feed Slide
Assembly 1. Verify the feed slide assembly slides in the feed tray.
Feed slide/tray binds.
2. Press the feed slide pawls to verify crisp spring action.
Springs are binding, weak or broken.
3. Install feed tray (WP 0041 00), feed slide assembly (WP 0041 00), and the secondary drive lever (WP 0041 00). With the bolt in the forward position and the feed slide assembly to the left, make sure guide rod spring is touching the inside wall of the top cover.
Top cover will not close.
Guide rod spring is bent or out of adjustment.
Primary/ secondary drive levers do not properly interconnect. and burrs along the rails of the tray. Inspect for rust. Ensure rails are well lubricated.
Feed tray is cracked.
Rails are burred. Rust is present.
0039 00-6
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) - Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF: tray pawl to verify crisp spring action without binding.
There is relative movement between the pin and the pawl or the
Secondary Pawls Press and release to verify crisp
spring action. Springs are weak or
broken. Pawl is broken.
9 Round Positioning
Block Slide the block in the keyholes
to verify it is tight. Pins are bent, loose or missing.
10 Alignment Guide
Assembly Verify the alignment guide pin
is tight. There is relative
movement between the spring and pin.
TM 9-1010-230-23&P 0039 00
0039 00-7
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
Appropriate eye protection is recommended when cleaning the weapon and/or its parts.
CAUTION CAUTION CAUTION CAUTION
Do not immerse the ogive assembly in cleaning solvent.
Solvent dilutes the internal lubricant.
Inspect for rust and damaged
or missing parts. Rust is present. Slotted washer is worn or split.
12 Receiver 1. Verify the three welded
pins (1) are present. One or more pins are missing.
2. Remove the bolt and backplate assembly (WP 0041 00). Inspect internal rails (2) for burrs.
Inspect feeder link guide (3) for galling or burrs.
Check for cracks on weld seams. Inspect all surfaces for rust.
Rails or feeder link guide are burred (galled). Weld seams are cracked. Rust is present.
3. Inspect receiver interior and right-hand inner rail for cracks and rust.
Cracks are visible. Rust is present.
1 L K 0 7 2
1 2
3
0039 00-8
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) - Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
13 Bolt and
Backplate Assembly
1. Verify the assembly is clean, lubricated, and has no rust.
Rust is present.
2. With the bolt and backplate assembly removed from the receiver (WP 0041 00), the firing pin should retract.
Firing pin does not retract.
ammunition which has been cycled through the weapon.
Conduct the dummy round test:
1. Manually push a dummy round down the bolt.
Verify the pawl snaps behind the rim of the case prior to compression of the bolt fingers.
Bolt pawl does not snap back to retain the dummy round.
NOTE NOTE NOTE NOTE
Where erosion (chipped) is severe enough to interfere with the function of the round being fed into the bolt fingers, replace the bolt.
2. Push the dummy round out of the bolt fingers.
Verify the round passes easily out of the bolt fingers. If still binding, disassemble, inspect, and replace damaged parts.
(Army: Evacuate to Direct Support Maintenance).
Dummy round binds when manually pushed through the bolt fingers.
TM 9-1010-230-23&P 0039 00
0039 00-9
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
14 Vertical
Cam Assembly
1. Remove the vertical cam assembly and the primary drive lever (WP 0041 00).
Vertical cam is bent.
2. Inspect the chromed surface (1) for burrs, pits, nicks, scratches, and aluminum buildup.
Remove any aluminum deposits (buildup), surface imperfection, or dullness using 600-grit silicone carbide abrasive paper, abrasive cloth or wood block. Remove any sharp edges with a stone.
There is aluminum buildup on the chromed surface. Rust on chromed surface.
21 1 L K 0 7 3
3. If pits are found, measure the distance of the pit from the edge, using a dial caliper. If pits are farther than .030 from the edge, replace the vertical cam assembly. (Army: Evacuate to Direct Support
Maintenance.)
Pits are visible within .030 from edge on chromed surface.
4. Verify free movement of the
drive lever lock (2). Drive lever pin is loose or missing. Lever binds.
0039 00-10
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) - Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
15 Weekly Primary
Drive Lever Inspect for burrs around the pivot post (1) and all surfaces.
Remove burrs with a stone.
Lever is burred. Pivot post is worn or burred.
1 L K 0 1 9
1. Inspect the function and general condition of the following (MK 19 Mod 3 only):
Handle locks Slides
Arm mechanism Lock plungers (tips)
Parts are missing, broken, bent, or show signs of wear.
2. Check grooved rails (1) for burrs. Remove burrs with a stone.
Rails are bent or burred.
TM 9-1010-230-23&P 0039 00
0039 00-11
PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) - Continued
Table 1. Preventive Maintenance Checks And Services For The MK 19 Mod 3 Machine Gun – Continued
ITEM
PROCEDURE EQUIPMENT NOT
READY/AVAILABLE IF:
3. Apply light coat of lubri-cant under each handle lock (2) and between each charger housing and receiver.
Whenever a new receiver sear is installed, also install a new bolt sear. Adjust the gun's timing.
(Army: Evacuate to Direct Support Maintenance.)
1. Inspect receiver sear (1) for wear. Replace if worn, observing NOTE, above.
Receiver sear shoulder is worn.