Sabroe SMC 104 106 108 112 116 Oil Pump Assembly

Sabroe SMC Compressor Oil Pump Assembly (SMC 104 / 106 / 108 / 112 / 116)

Engineered specifically for heavy-duty industrial refrigeration and marine provisions/cargo systems, the positive-displacement gear oil pump assembly for Sabroe SMC reciprocating compressors ensures consistent hydrodynamic lubrication across all journal bearings, wrist pins, and dynamic mechanical shaft seals.

Operating under harsh maritime duty cycles and continuous shore-based industrial loads, this pump assembly directly integrates into the compressor end-cover housing. It is mechanically driven via an Oldham-style slot/tang drive off the compressor crankshaft. The pump maintains regulated differential oil pressure critical for both internal hydrodynamic bearing films and the hydraulic actuation of the compressor’s internal cylinder unloading mechanisms (Mk 1 through Mk 5 series).

Model Details

• Manufacturer: Sabroe (Johnson Controls Industrial Refrigeration)
• Pump Series: Internal Gear Oil Pump / End Cover Lubrication Pump
• OEM MPN (Assembly Kits):
  • Clockwise (CW) Rotation: 3184-354 / 3184.354
  • Counter-Clockwise (CCW) Rotation: 3184-353 / 3184.353
  • Pump Housing Sub-Assembly: 3184-350 / 3184.350
  • Regulating Valve Internal Kit: 3184-351 / 3184.351
  • Legacy Drive / Pump Coupling Kit: 3184-333 / 3184.333
• Interchangeable / Superseded Part Numbers:
  • Sabroe Pos. 4 / Pos. 5 lube group 0661-680-EN series
  • Ralco: SKT70353 (CCW), SKT70354 (CW)
  • Johnson Controls / York OEM: 534B0354H01, 534B0353H01

Features

1. Bi-Rotational Design Capability: Available with factory-configured reversing valve internal port plates or dedicated directional gear alignments (CW/CCW) to prevent loss of lubrication during reverse-rotation phases.
2. Integrated Hydraulic Actuation Support: Delivers steady oil feed directly into the hydraulic unloader galleries, enabling positive cylinder loading and unloading steps on 4, 6, 8, 12, and 16-cylinder blocks.
3. Precision Helical/Spur Gear Mesh: Machined to tight radial and axial running tolerances to maximize volumetric efficiency even at high operating temperatures and during diluted-refrigerant cold starts.
4. Direct Crankshaft Coupling: Driven directly via positive tang/slot mechanical interface, eliminating internal drive-belt stretch or slippage.
5. Built-in Pressure Relief & Differential Bypass: Direct porting to internal differential regulation valves safeguarding against hydrostatic overpressure during low-temperature oil startups.

Technical Specifications

Frequently Asked Questions

How do I know if my Sabroe SMC compressor oil pump is failing?

Early indicators include unstable oil pressure gauge fluctuations, delayed hydraulic unloader response (compressor failing to step load/unload), differential oil pressure dropping below 1.5 bar over crankcase pressure, and metal flakes caught in the suction filter screen.

What is the correct oil pressure for Sabroe SMC 104, 106, 108, 112, and 116 compressors?

The standard operating oil pressure should be maintained between 2.0 and 4.0 bar above the suction (crankcase) pressure. An internal differential pressure switch (UniSAB or analog differential pressure control) is typically set to trip if the net differential drops below 1.2–1.5 bar for longer than 30–60 seconds.

Are the oil pumps interchangeable between Sabroe SMC Mk 2, Mk 3, Mk 4, and Mk 5?

Most Mk 3, Mk 4, and Mk 5 SMC 100 series compressors share common pump housing footprints, but check the rotation direction (CW vs. CCW) and whether your end cover incorporates internal or external bypass routing. Always match the OEM assembly part number (3184-353 or 3184-354) before mounting.

Can I run the Sabroe SMC oil pump with ammonia (R717) and synthetic POE oils?

Yes. The pump body and gear train are fabricated from cast iron and hardened carbon steel, making them completely compatible with anhydrous ammonia (R717), fluorinated HFC/HFO refrigerants, and all major mineral, alkylbenzene, and synthetic polyolester lubricants.