



The QSB5.9 Cummins platform is the high-performance heart of the Kawasaki 70ZV. Utilizing a 24-valve cylinder head and advanced electronic controls, this engine is designed to provide the rapid throttle response and heavy-lifting power required for high-cycle wheel loader applications. Our remanufactured long block is engineered to exceed OEM standards, ensuring your machine stays out of the shop and on the job site.
Vibration Mitigation: A fully balanced rotating assembly ensures your loader operates with maximum smoothness. By eliminating internal harmonics, we protect your hydraulic pump drives, transmission, and operator comfort from the parasitic vibrations that lead to premature wear.
At Choate Engineering Performance, we remanufacture the QSB5.9 to surpass original factory specifications. Our process utilizes rigorous CNC blueprinting to ensure the extreme reliability required for heavy-duty earthmoving.
Each of our engine blocks are CNC blueprint machined using state-of-the-art CNC machines. This process ensures perfect dimensions, precise tolerances, and optimal alignment. This starts with decking the surface of the block to achieve the necessary flatness and smoothness (Ra 30 or better) required for flawless sealing with MLS head gaskets. The cylinders are then diamond honed to an extremely tight tolerance to match the piston diameter (within the nearest 0.0001 inch). Following honing, the main bearing bores are line honed to establish a true, straight centerline for the crankshaft. Finally, the cylinder bores are bored to a true 90 degree angle from the crankshaft centerline.
Our cylinder heads are fully machined and enhanced in-house to improve airflow and reliability. Each head is first magnafluxed and pressure tested to ensure they are free of any cracks or leaks. The surface is then precision decked to an extremely smooth finish, guaranteeing the necessary flatness for a perfect seal with MLS head gaskets. Internally, the valve seats are machined to optimize airflow and prevent common failures, and the entire valve train geometry is blueprinted to specific tolerances to reduce lifter preload and prolong component life.
The balancing of the rotational assembly is crucial for eliminating vibration and maximizing engine longevity. This precision work involves checking and correcting the balance of the crankshaft, connecting rods, and pistons. The crankshaft is thoroughly checked for run-out and inspected for fatigue before being polished and ground to strict concentricity tolerances (0.0005 or less) to ensure the new bearings receive the best possible surface. Rods are inspected and conditioned, and all bearing clearances checked to ensure proper fitment with the new bearings. Each of the pistons, rings, and pin retainers are meticulously weight matched (to a tolerance of 2 grams or less) prior to crank balancing. Then the entire assembly is dynamically balanced on specialized equipment. This ensures that the engine runs smoothly, minimizing stress on the bearings, and extends the overall life of the components.
In the dirt and gravel business, downtime is the enemy. At Choate, we stand behind the precision engineering of our QSB5.9 Long Block Engines with a comprehensive 2-Year / 2,000-Hour Warranty.
We understand that the Kawasaki 70ZV is expected to perform in harsh, dusty, and high-heat environments. Our warranty is designed to give fleet managers and owner-operators total peace of mind, ensuring that your remanufactured engine is protected against defects in materials and workmanship for the long haul.
FREIGHT / SHIPPING CHARGES

CHOATE ENGINEERING PERFORMANCE SHALL NOT BE RESPONSIBLE, NOR SHALL IT PAY ANY FREIGHT/SHIPPING CHARGES.
ADDITIONAL INFORMATION

As consideration for the above warranties, the buyer agrees they will take no action, statement, characterization, or implication regarding Choate Engineering Performance that may in any manner be interpreted as disparaging to Choate Engineering Performance or the reputation of Choate Engineering Performance. Any violation of this is a material breach, entitling Choate Engineering Performance to void any warranty.
