KANGDA 2QT36 BH2QT90R9 – Precision Fuel Pump For YC2115 Diesel Engines

The KANGDA 2QT36 fuel injection pump, identified by order number BH2QT90R9, is a dedicated high-pressure diesel injection pump engineered for the YC2115 engine platform. Operating at a rated speed of 2400 RPM and supporting a power output of 37.1 kW, this pump is specifically calibrated for agricultural and industrial applications where the Yuchai YC2115 is the prime mover. As a critical component in the diesel fuel system, it ensures precise fuel delivery, atomization, and combustion efficiency, directly impacting the engine's reliability and thermal efficiency for end-users ranging from tractor operators to stationary power plant technicians.

This injection pump is exclusively matched to the YUCHAI YC2115 engine, a prevalent power source in the Southeast Asian and South American agricultural markets. It is a direct replacement for OEM components found in Dongfeng tractors, Foton harvesters, and generator sets utilizing this specific Yuchai block. Unlike universal aftermarket pumps, the 2QT36 BH2QT90R9 retains the exact governor spring tension and static timing marks required for the YC2115 2400 RPM governor cut-off point. This ensures that the fuel delivery curve aligns with the engine 37.1 kW rated load, preventing the common issues of under-fueling (loss of PTO power) or over-fueling (excessive black smoke and EGT spikes). For workshops handling mixed fleets, verify the engine serial number prefix to confirm fitment, as the YC2115 has a distinct camshaft lobe profile compared to the YC2118.

When installing the KANGDA 2QT36 unit, the most critical step is the alignment of the drive gear timing marks before engaging the starter. The YC2115 relies on a gear train-driven pump; failing to record the injection timing prior to disassembly results in incorrect advance and a no-run condition. We recommend using a dial gauge on the pump plunger to find the precise spill port closing point relative to the engine TDC mark on the flywheel. Furthermore, do not reuse high-pressure pipes that have been previously tightened; the ferrule deformation is single-use only. Re-bending or reusing these pipes leads to micro-cracks and leakage under the high-pressure pulses generated at 2400 RPM, compromising the fuel atomization quality. Replace all sealing washers and the overflow valve during the pump swap to maintain the correct gallery pressure and avoid vapor lock.

Given the tight tolerances of the BH2QT90R9 plunger and barrel, fuel contamination is the primary accelerator of wear in agricultural environments. The ultra-low sulfur diesel commonly available in export markets lacks the lubricity that older pumps relied on; therefore, using a fuel additive with lubricity enhancers is highly recommended for the YC2115. The most destructive factor is water ingress; even a small amount of water causes microscopic pitting on the plunger surface, leading to internal leakage and a drop in rail pressure. Workshops must ensure the primary fuel filter and water separator are serviced more frequently than the engine oil schedule when this pump is in heavy tillage use. If the pump exhibits signs of bearing flaking or internal wear, the entire fuel system including the injectors and return lines must be flushed to remove metal chips that would destroy the new pump.

Q1: Is the KANGDA BH2QT90R9 a direct bolt-on replacement for the YC2115, or does it require timing recalibration?
A: It is a direct physical fit; however, static timing recalibration is mandatory. While the keyway aligns, variations in engine wear necessitate a dial gauge check to set the fuel delivery advance precisely at the factory spec for the 2400 RPM power rating.

Q2: How does this 2QT36 pump differ from the BH4QT90R9 model?
A: The primary difference is the cylinder count. The BH4Q is a 4-cylinder pump suited for larger engines, whereas the BH2QT90R9 is specifically for the 2-cylinder YC2115 architecture, governing only two plunger assemblies.

Q3: Does this pump include the automatic advance mechanism, and is it serviceable?
A: Yes, it incorporates a mechanical centrifugal advance. This unit can be serviced with a calibration bench; however, for a workshop without a test stand, we recommend replacing it as a complete assembly to maintain the correct advance curve.

Q4: What are the immediate symptoms of a failing 2QT36 pump on the YC2115?
A: Look for hard starting, a drop in maximum power below the 37.1 kW threshold, unstable idle speed, and an increase in diesel knock. A return flow test showing excessive fuel bleed-off is a positive indicator of plunger wear.

Q5: Can I use a generic repair kit to rebuild this KANGDA pump?
A: We strongly recommend using only KANGDA-sourced kits. Generic kits often have incorrect plunger lead angles and spring rates, which fail to deliver the specific fuel volume needed for the YC2115 combustion chamber design, leading to poor performance and warranty voidance.