F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
4 L
UBRICATION
PAGE 4-54
to leak oil. In this case, replace the balance valve internal assembly with a plug assembly,
Ariel Part Number A-10330. DO NOT RUN UNIT WITH LEAKY BALANCE VALVES. A valve
seal repair kit, Ariel Part Number A-8005-K, is also available.
Maintain the system by recording the pressures and cycle times of the lubrication system at
least once a day. Readjust valves as required to keep pump systems pressure balanced for
best results.
Frame Lubricating System - Description
The frame lubricating system supplies oil to the internal frame running gear. The cylinders are
supplied with lubrication by the force feed system (see “Force Feed Lubrication System - De-
scription” on page 4-31). The oil level regulator outside of the crankcase, or separate oil sump
in the case of a dry sump crankcase, maintains the proper oil level in the sump.
Frame lubrication is drawn from the sump through the suction strainer into the oil pump that
is mounted on the crankcase auxiliary end cover. The pump's discharge is piped to an oil
cooler mounted on the compressor skid and is temperature controlled with a thermostatic
control valve. Oil returns from the cooler to the oil filter mounted on the auxiliary end of the
crankcase. Pressure gauges are provided on the filter inlet and outlet. Normal pressure drop
through a clean filter is 2 to 6 PSID (0.15 to 0.4 bar
d
), at normal operating temperature.
From the filter, oil travels through a pressure regulator to an oil gallery cast in the crankcase
and running the length of the crankcase.
Drilled holes from the gallery through the bearing saddles deliver oil to the crankshaft bear-
ings.
Passages drilled diagonally through the crankshaft from the crank journals to the crank pins
deliver oil to the connecting rod bearings.
Holes drilled through the length of the connecting rods deliver oil to the connecting rod bush-
ing.
Oil travels from the bushing through holes drilled in the middle of the crosshead pin to the
hollow crosshead pins, and from there to the crosshead bushings.
Drilled passages from the oil gallery deliver oil at full system pressure through external tubing
to lubricate the top and bottom of each crosshead. Run-off from the shoes, crosshead, and
connecting rod bushings collects in the crosshead guide and drains back to the crankcase.
Lube Oil Strainer, Filter & Filter Installation Instructions
Lube Oil Strainer
The strainer is located on the auxiliary end of the crankcase below the oil level. It is provided
to protect the oil pump from debris that might cause damage. The strainer basket should be
taken out and washed in an appropriate solvent whenever the lubricating oil is changed. For
dry sump frames the lube oil strainer is shipped loose (not installed) from the Ariel factory.
