F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
5 - M
AINTENANCE
PAGE 5-22
NOTE: DO MIX BEARING SHELL PART NUMBERS ON AN INDIVIDUAL MAIN OR
CONNECTING ROD. BOTH HALF SHELLS MUST HAVE THE SAME PART
NUMBER.
8.
Oil crankshaft bearing surfaces with new clean lubricating oil, same type as is
used in the frame, before installing the main bearing cap.
9.
Replace thrust plates on bearing cap #1, if crankshaft thrust clearance is not
within tolerance.
10. Install the bearing cap, containing a new half bearing shell. Be sure the dowels
in the bearing caps are aligned with the holes in the crankcase base. A set
screw on top of each dowel prevents it from backing out. Install the cap screws
and tighten them in an alternating (criss-cross) pattern to the torque value given
in Table 1-12 on page 1-16.
11.
Repeat one throw at a time for each bearing until all main bearings are replaced.
12. Check crankshaft journal bearing jack (at each bearing) and crankshaft thrust
clearances to values in Table 1-3 on page 1-10. See "Main Bearings - Checking
Clearances" on Page 5-14. Record readings on a copy of form on Page 5-48.
13. If readings are not within tolerance after installing new bearings, contact your
packager or Ariel before proceeding.
14. Account for all tools, measuring and lifting equipment, supplies, replaced parts,
etc. to be sure they have all been removed from inside the crankcase and then
re-install the gaskets and top cover. Before installing a gasket, apply an anti-
seize lubricant to both sides or to the metal seating surfaces. This will help to
hold the gasket in place during assembly and aid in easy of removal. Tighten
cover bolts hand wrench tight.
15. Replace coupling spacer to packager’s recommendations or remove lockout.
16. After replacing bearings, thoroughly pre-lube compressor to be sure that bear-
ings are lubricated and to help remove foreign materials from the lube system.
17. When starting the compressor after the first 10 minutes of run time, after one
hour, and after four hours, shutdown compressor and remove the frame top
cover. Check the bearing cap temperatures using a temperature probe (hand
held thermocouple probe or infrared thermometer), record on a copy of form on
Page 5-48.
DO NOT PLACE ANY PART OF YOUR BODY INSIDE THE
CRANKCASE WITHOUT OBSERVING THE “CAUTION” ON PAGE 5-2.
Com-
plete remaining information on the “Bearing Log / Conditions After Replacing
Bearings” form and fax copy to Ariel Technical Services. Keep a copy with the
compressor records.
Crankshaft - Installation
1.
Put new bearing shells in place on the saddles in the frame and in the bearing
caps to "Main Bearings - Removal and Installation w/Crankshaft Removed" on
Page 5-20. Move the connecting rods to their full outer position. Oil crankshaft
bearing surfaces with new clean lubricating oil, same type as is used in the
frame, before installing. While the crankshaft is being lowered very slowly into
the crankcase (if suspended by a crane with a nylon sling, use second throw
crank pin), maneuver the drive end into the crankcase to clear the seal housing
opening. Use clean gloves as during removal. Lower crankshaft into place so
that both drive end and auxiliary end journals touch the bearing saddles at the
