FIGURE 4-27. Valve Seat Insert Bore Measurement.

Custom Search

FIGURE 4-25. Valve Seat Insert Removal.

TM-55-1905-223-24-1 Main Propulsion Engine for Landing Craft Utility (LCU) NSN 1905-01-154-1191 Manual

FIGURE 4-28. Air Deflector Replacement.

TM 55-1905-223-24-1

(5)

Measure the inside diameter and the depth of the insert bore (FIG. 4-27).

Verify bore meets

following specifications.

Diameter (6)

Depth (7) and (8)

Intake bore:

3.377 to 2.378 inch

0.512 to 0.517 inch

(60.38 to 60.40 mm)

(13.00 to 13.13 mm)

2.377 to 2.378 inch

0.492 to 0.497 inch

(60.38 to 60.40 mm)

(12.50 to 12.62 mm)

NOTE

Oversize valve seat inserts are available in the following sizes.

Outside Diameter

Depth (Thickness)

0.010 inch (0.25 mm)

Standard

0.020 inch (0.51 mm)

0.005 inch (0.13 mm)

0.030 inch (0.76 mm)

0.010 inch (0.25 mm)

0.040 inch (1.02 mm)

0.015 inch (0.38 mm)

FIGURE 4-27. Valve Seat Insert Bore Measurement.

(6) If inside diameter is not within specification, machine the valve seat insert bore for an oversize seat.

A press fit within 0.0025 to 0.0045 inch (0.064 to 0.114 mm) between the valve seat insert and the

bore must be maintained.

(7) Install air flow deflectors in intake ports. Ensure tang on the deflector is in alignment with the hole on

the notch in the head FIG. 4-28.

(8) Identify the correct valve seat insert (FIG. 4-29).

NOTE

Install insert with 30 degree angle pictured as shown.

4-25