Learning chapter

Two-Stroke Construction

10 lessons

Inside the big two-stroke: engine structure, crankshaft types, main/guide/thrust bearings, chain drive and charge-air coolers — with inspection and failure points.

This chapter collects 10 illustrated lessons on Two-Stroke Construction as part of Marine Propulsion & Diesel Engines, ordered as they are best studied. It opens with Two-Stroke Structure — Frame, Tie Rods, Liner, Piston & Crosshead, Marine Crankshafts — Builds, Bedplate, Chocks & Alignment, Engine Bearings — Renewal, Crosshead to Thrust Block, Camshaft Chain Drive, Hydraulic Tensioners & Timing Synchronisation, Crosshead Assembly, Guide Clearances & Piston Rod Stuffing Box, Cylinder Liner Wear, Calibration & Cold Corrosion and 4 more. Each lesson is written for MEO oral and written preparation: definitions first, then how the system behaves, then the checks and figures used in practice.

Explore the lessons

01 Two-Stroke Structure — Frame, Tie Rods, Liner, Piston & CrossheadLearn two-stroke structure: tie-rod tensioning and breakage, bedplate to cylinder block, cover mountings, liner scavenge ports, concave piston cooling, crosshead side-thrust.5 sections 02 Marine Crankshafts — Builds, Bedplate, Chocks & AlignmentLearn crankshaft construction, fabricated bedplate girders, holding-down bolt tension with wedge test, epoxy resin chocking procedure, witness marks and misalignment causes.5 sections 03 Engine Bearings — Renewal, Crosshead to Thrust BlockLearn engine bearings: 22-step main-bearing renewal with depth gauge and hydraulic jacks, hydrodynamic lubrication, crosshead oil timing, thin-shell mains, thrust pads.6 sections 04 Camshaft Chain Drive, Hydraulic Tensioners & Timing SynchronisationMaster marine camshaft chain drives: roller chain wear, 10-20 pitch elongation limits, hydraulic tightener ratchet mechanics, and camshaft re-timing at sea.6 sections 05 Crosshead Assembly, Guide Clearances & Piston Rod Stuffing BoxMaster marine crosshead assemblies: oscillating pin lubrication, guide shoe clearances, stuffing box tri-zone sealing rings, and running-in protocols.7 sections 06 Cylinder Liner Wear, Calibration & Cold CorrosionMaster marine cylinder liners: bore cooling, cold corrosion acid chemistry, cloverleaf wear, micrometer calibration, wear limits, and wave-cut refurbishment.5 sections 07 Piston Crowns, Piston Rings & Thermal MechanicsMaster marine diesel pistons: Cr-Mo crown metallurgy, cocktail shaker cooling, CPR rings, butt clearances, groove wear, and ring sticking prevention.5 sections 08 Exhaust Valve Actuation, Air Spring Mechanics & Spindle MetallurgyComplete guide to two-stroke exhaust valves: hydraulic pushrods, pneumatic air spring mechanics, Nimonic 80A metallurgy, hot corrosion, differential seat angles, and overhaul.7 sections 09 Engine Bedplate Foundation, Holding Down Bolts & Epoxy ChockingMaster marine diesel bedplates: bearing saddle cracking, long holding down bolts, hydraulic tensioning, Chockfast Orange resin chocking, and side/end chocks.6 sections 10 Crankshaft Alignment, Web Deflections & Bearing ClearancesMaster marine crankshaft alignment: dial indicator web deflections, calculation formulas, deflection curve interpretation, bridge gauge clearances, and tri-metal bearings.8 sections