KANGDA 2Q58 / BH2Q85R8 – Direct-Fit Injection Pump For SD2105T Shantuo Power Units

When a Shandong Tractor SD2105T loses its lugging power or starts smoking under load, the culprit often traces back to fuel delivery irregularities. The KANGDA 2Q58 (order code BH2Q85R8) steps in as a dimensionally identical replacement for the factory-original pump, restoring the 26.46 kW output at 2400 rpm that these two-cylinder workhorses demand. This is not a universal retrofit-it is a bore-matched, stroke-calibrated unit built specifically for the TS354-series agricultural tractors, enabling repair shops to skip machining or shim-stacking guesswork.

Every BH2Q85R8 unit leaves the bench with plunger stroke and delivery valve opening pressure preset to SD2105T workshop manual values. The pump body carries the original 12C000-1111100 footprint, ensuring the mounting flange aligns without spacer adjustments. Critical parameters include a cam lift of 7.5 mm, injection order of 1-2, and a static timing mark at 20° before top dead centre. Unlike electronically trimmed common rail injectors, this mechanical jerk pump relies on precise plunger barrel fitment-clearance below 0.005 mm is non-negotiable for cold start performance. Shops ordering this SKU receive a unit already flow-tested at 300 bar nozzle opening pressure, with governor cut-off verified at 2640 rpm to prevent overspeed conditions during PTO operation.

The SD2105T engine powers not only Shantuo's TS354 row-crop tractors but also stationary gensets and irrigation pumps in off-grid farms. For workshop owners serving mixed agricultural fleets, the BH2Q85R8 offers interchangeability with earlier 2Q80 and 2Q82 variants-a single stock number covers multiple chassis years. Field data shows these engines operate at 85% load factor during ploughing seasons, making fuel injection timing drift a common failure mode. The KANGDA pump addresses this with hardened camshaft journals and a governor spring calibrated to maintain ±5 rpm stability from idle to rated speed, reducing operator complaints about RPM surging when engaging hydraulics.

Mounting this pump demands clean hands and a torque wrench-no press-fit tools required. Align the drive gear index mark with the pump flange dot before sliding the unit onto the mounting studs. A common oversight: failing to bleed the low-pressure supply line before cranking, which aerates the high-pressure circuit and mimics injector failure. After hand-tightening the three flange nuts to 25 Nm, rotate the crankshaft two full turns and re-check the timing mark-the BH2Q85R8's keyway slot allows micro-adjustment within ±2°. For fleets running biodiesel blends up to B20, we recommend replacing the delivery valve springs every 2000 hours; the KANGDA unit ships with chrome-silicon springs rated for aggressive fuel chemistries.

When a SD2105T returns with uneven firing, isolate the pump before pulling injectors. Connect a pressure transducer to the fuel inlet-if pressure drops below 1.5 bar during cranking, suspect the vane-type supply pump inside the governor housing. For intermittent stall, measure the governor weight travel: worn pivot pins cause erratic fuel rack movement, a fault fixed only by replacing the entire governor assembly, not just the spring. The BH2Q85R8's cast-iron housing also includes a manual bleeding screw on the filter head, enabling quick air purging without diagnostic software-a feature that independent repairers value over electronically managed common rail counterparts.

Q1: Does the BH2Q85R8 come with a new delivery valve holder, or must we reuse the old one?
A: The KANGDA 2Q58 ships as a complete pump assembly including delivery valve holders, plunger barrel, and governor spring, but excludes high-pressure fuel lines and injector nozzles-reuse existing lines after inspecting flare seats.

Q2: Can we exchange a worn 2Q80 pump core for this BH2Q85R8 under a reman programme?
A: Yes, core returns are accepted provided the housing is crack-free and the drive shaft splines show less than 30% wear; the plunger and barrel are discarded regardless of condition.

Q3: What is the expected shelf life for this pump if kept as emergency backup stock?
A: Store in a sealed plastic bag with desiccant; the internal springs and plunger surface remain serviceable for up to 36 months without corrosion, provided ambient humidity stays below 60%.

Q4: How do we verify the pump's calibration matches our specific TS354 tractor without a test bench?
A: Install a temporary fuel flow metre on the return line-at 2400 rpm no-load, flow should not exceed 40 ml/min; above that indicates internal bypass, not calibration error.

Q5: Is this pump compatible with the SD2105T's original 8.5:1 compression ratio after a cylinder head resurface?
A: Yes, the BH2Q85R8's injection advance is mechanical and unaffected by head skimming-only the static timing setting needs rechecking if the camshaft gear was disturbed.