Kawasaki 70Z-II, 70Z-III & 70Z-IV Cylinder Head Reman - Workhorse (5.9L 12V)

Part Number / SKU: CEP59KA12VWHR

Keep your heavy equipment operational under the most demanding workloads. The Workhorse tier cylinder head for the Kawasaki 70Z-II, 70Z-III, and 70Z-IV wheel loader is specifically engineered for sustained heavy-duty industrial work, continuous duty cycles, and extreme thermal loads. Assembled using a renewed, pressure-tested OEM core combined with brand-new, high-quality internal components, this cylinder head integrates premium durability upgrades to handle elevated cylinder pressures and eliminate common field failures.

Upgrades Over the Daily Driver: Precision O-Rings

Severe industrial operation causes rapid thermal expansion, which is the leading cause of head gasket failure in heavy equipment. The Workhorse model solves this by features precision-cut O-rings machined directly into the deck surface. This mechanical modification locks the head gasket securely in place, dramatically improving sealing under high cylinder pressures and severe operating temperatures to ensure zero combustion leaks.

Premium Component Breakdown

• Remanufactured Casting: Built from a high-quality OEM core casting that has passed rigorous magnetic testing and is machined to like-new specifications.

• New Wear Components: Equipped with all-new, high-quality valve seats, valve seals, and valve guides.

Key Features and Heavy-Duty Fixes

This head features critical performance and structural upgrades, backed by an intense inspection protocol to guarantee every industrial specification is met.

• 40 PSI Pressure Testing: After machining, every cylinder head is pressure-tested at 40 PSI to confirm zero leaks and ensure casting integrity.

• Blow-Proof Plugs: Threaded, blow-proof plugs are installed in the top of the head for increased security and leak prevention, replacing factory pressed-in plugs that fail under thermal stress.

• Final Quality Control: The head undergoes an extensive final cleaning and strict quality control inspection. A detailed sign-off sheet is generated, measuring and recording critical specifications using a profilometer, including:

  • Valve Recessions

  • Stem Heights

  • Installed Spring Heights

  • Spring Pressures

  • Keeper and Lock Positions

  • Roughness Average (RA) Finish

Precision Machining Process

Aero Engines Inc has incorporated critical modifications to address common factory vulnerabilities of the 5.9L industrial cylinder heads, drastically improving field reliability:

• Optimal Sealing Surface: The deck is resurfaced to meet or exceed OEM specifications for Roughness Average (Ra), maximizing the sealing surface performance for the head gasket.

• Valve Train Geometry Alteration: The head is custom blueprinted to alter valve height and valve recession, achieving maximum reliability under continuous loads.

• Lifter Longevity Fix: Valve stem heights are precisely altered to optimize valvetrain geometry and remove excessive preload. This crucial modification decreases wear and significantly extends the life of the lifters and camshaft.

• Optimized Flow and Sealing: Valve seats are cut with a precise three-angle profile to optimize efficiency and ensure an airtight seal.

• Valve Prep: Valves are reground and margins are meticulously inspected to guarantee proper sealing against the new seats.

• All-New Wear Components: New valve stem seals, valve seats, valve guides, and injector cups are installed across the board.

Meticulous Cleaning and Prep Process

Our commitment to quality begins before machining, with an intensive cleaning and stress-relieving process to ensure a flawless starting point:

• Magnetic Particle Inspection (MPI): Each core is subjected to MPI testing to thoroughly check for any cracks or subsurface imperfections.

• Thermal Stress Relieving: The head undergoes a stress-relieving process in a specialized furnace to eliminate residual industrial oils and grease by turning them into ash.

• Material Relaxation: The head is shot-blasted to remove rust and scaling. This crucial step relaxes the cast iron material before precision machining begins.

• Thread Prep: All broken bolts and studs are professionally removed to ensure threads are clean, chased, and ready for a seamless installation.