Ariel Heavy Duty Balanced Opposed Compressor JGM/2

Warning: Refer to the correct valve assembly drawing and parts list and Hoerbiger's literature in the Ariel Parts Book before servicing any valve.

Valves have different springing for different pressure levels. The cylinder cover sheet in the Parts Book lists the valve originally supplied with each cylinder.

If different operating pressures are encountered, then different springs may be required.

Suction valve selected based on operating suction pressure?

Discharge valve selected based on operating discharge pressure?

Enter the operating speed (RPM)

Enter the suction temperature of the gas

Contact Ariel in Mount Vernon, for assistance in valve selection.

Remove the cap screws from the drive chain eccentric adjustment cap and rotate cap to loosen the chain

Remove all piping (tubing) from the pump

Remove fasteners from pump mounting adaptor

Measure the distance from the sprocket drive face to the pump mounting adaptor face

Remove the sprocket set screw from the oil pump

Pull the sprocket from the pump shaft

Remove the No. 204 Woodruff key

Caution: Ensure cylinders are completely vented before starting.

Crosshead guide side covers removed

Cylinder head (or VVCP) removed

Crankshaft positioned to near its inner dead center position

Crosshead-balance nut set screws backed off

Crosshead-balance nut turned off the piston rod

Piston and rod assembly removed

Crankshaft positioned to near its outer dead center position

CAUTION!: BE SURE THAT ALL PRESSURE IS RELIEVED FROM THE COMPRESSOR CYLINDERS PRIOR TO REMOVING PACKING.

Packing diaphragm and oil wiper packing removed

All tubing connections from the top of the packing flange and the primary vent tube from the bottom of the flange disconnected

Twelve point cap screws that hold the pressure packing flange to the cylinder removed

At this point do not remove the small nuts from the studs. These studs hold the entire packing case together so it can be removed as an assembly.

Pressure packing removed into the crosshead guide

Remove the top cover from the crankcase (connecting rod and chain access covers on the JGI) and the side covers from the crosshead guides.

Remove the piston and piston rod as described in “Piston and Rod” on page 5-27.

Move the throw to near the outer dead center position.

Remove the crosshead as described in “Crosshead - Removal” on page 5-11, while supporting the connection rod so that it does not drop.

Turn the crankshaft until the throw is near to its highest point position. Completely loosen the connecting-rod-cap bolting and remove the top two capscrews.

Separate the rod cap from the rod. Use the bottom two rodcap capscrews as a handles to pull on the bottom of the rod cap while tapping the top face of the rod cap with a semi-soft faced hammer. Do not pull or strike the rod cap too hard; it may break the rod cap dowels. Work the rod cap away from rod as evenly as possible. Separating the two parts unevenly may break the rod cap dowels or cause them to bind in the rod dowel holes. See Figure above.

Remove the rod cap and its bearing half shell.

The bearing shell may fall out when separating the connecting rod and cap from the crankshaft pin. If bearing shells do not come loose, rotate/slide them out of the connecting rod and/or cap.

Turn the crankshaft throw to near the inner dead center position and remove the rod through the crosshead guide opening (or connecting rod access hole on the JGI).