JETStream 3000 series, Operation Manual, Page: 70 / 84

Operation Manual
62
Crosshead Inspection
1. Use a micrometer to measure the outer di-
ameter of the crosshead in three places and
record the measurements.
2. Add the three measurements and divide by 3
to get the average diameter.
3. Use an inside micrometer to measure the
crosshead bore in the power frame in three
places and record the measurements.
4. Add the three measurements and divide by 3
to get the average diameter.
5. Subtract the diameter of the crosshead from
the inside diameter of the crosshead bore. If
the remainder is greater than 0.012 in. (0.31
mm), the crosshead must be replaced.
Note:
New part clearances are as follows:
• Series 3000: 0.004 in. (0.1 mm) - 0.007
in.(0.2 mm)
• Series 3600/4200: 0.006 in. (0.15 mm) -
0.009 in. (0.23 mm)
6. Repeat for the remaining assemblies.
Assembly
1. Clean all surfaces of the crossheads, pins,
and connecting rods using brake cleaner.
2. Inspect all surfaces of the crossheads, pins,
and connecting rods for any signs of damage.
Replace any suspect or damaged parts.
3. Inspect the long bore oil passage through the
length of the connecting rod. Use a wire or a
long handle brush to clear passage if necessary.
4. Insert the connecting rod into the bottom of the
crosshead and line up the bores.
5. Lubricate the pin (Figure 123) with clean oil
and insert the pin into the hole in the side of
the crosshead.
6. Align the hole in the connecting rod with the
pin as it is slipped in.
7. Thread the first set screw into the crosshead
hole until it touches the pin, then back off a
1/4 turn. Slide the pin into position and tighten
the set screw ensuring the screw is engaged
in the counterbore of the pin. Tighten the set
screw to 30 ft lb (41 N·m).
8. Apply Loctite Red-271
©
onto the threads of the
second backup set screw.
9. Install the second set screw on top of the first set
screw. Tighten to 36 ft lb (49 N·m) (Figure 124).
10. The crosshead is now ready for installation in
the pump.
Figure 123: Pin Placement.
Figure 124: Second Set Screw Installation.
Pin
Crosshead