0445120237 Bosch Common Rail Injector 5263310 for Cummins QSL9, Case IH & New Holland

Genuine new Bosch 0445120237 common rail fuel injector (OE Cummins 5263310, Case 84347519) for Cummins QSL9 and ISL9 / L9 8.9L engines, Case IH Magnum and New Holland T8000 and TG tractors, and Kenworth and Peterbilt trucks running the PX-9 engine. Supplied brand new in the original sealed Bosch box, made in Brazil, and covered by a 1-year manufacturer global warranty.

This CRIN1-14/16 injector is electromagnetically actuated: a solenoid opens the control valve, and the injector meters diesel into the combustion chamber at rail pressure, with the timing and quantity the engine control unit commands. A matched set of correctly flowing injectors is what restores clean starting, a stable idle, full power under load and normal fuel consumption on a high-hour 8.9L engine.

Also known internationally as: Common Rail Injector (EN), Common-Rail-Injektor / Einspritzduse (DE), Injecteur Common Rail (FR), Iniettore Common Rail (IT), Inyector Common Rail (ES), Injector Common Rail (RO) - Bosch 0445120237 for Cummins QSL9, Case IH and New Holland.

Key features

Product details

OEM cross-reference numbers for Bosch 0445120237

Compare your original part number before ordering. Vehicle or machine model alone is not enough for compatibility confirmation.

The Bosch Exchange numbers and the OE codes marked "Bosch Exchange" identify the remanufactured version of this injector. They are listed so you can cross-identify the part you removed; the injector sold on this page is a genuine new Bosch unit.

Vehicle and machine compatibility

Compatibility must always be verified by the original Bosch part number, the OE number, the engine serial number or the number marked on the injector you removed. Model alone is not sufficient.

Engine and truck applications

Case IH and New Holland tractor applications

Technical information

Related diesel fuel system components

These components sit in the same fuel circuit as this injector and are commonly replaced or inspected with it. Manufacturers used different variants depending on engine build, model, power rating, emissions stage and production date, so another code may be the correct one for your engine. Identification is by the number on the part you removed, not by the machine model.

Shipping and warranty

Frequently asked questions

How do I know the Bosch 0445120237 fits my tractor or truck? Read the number marked on the injector you removed, or the OE number in your parts documentation, and compare it with the cross-reference table above. On Case IH and New Holland machines the usual OE number is 84347519; on Cummins-powered trucks and buses it is 5263310. Where a part number cannot be read, the engine serial number is the next reliable identifier. The machine model on its own is not enough, because the same tractor model was built with more than one injector variant.

What condition is this injector supplied in? It is a genuine new Bosch injector, delivered in the original sealed Bosch box, made in Brazil, with a 1-year manufacturer global warranty. Each unit is supplied with its injector body O-ring and a nozzle sealing washer.

Is Cummins 5263310 the same injector? Yes. Cummins 5263310, together with Cummins 4934411 and 4944476, are the OE references for this Bosch 0445120237. Cummins 5263310RX is the remanufactured version of the same number.

My machine is listed with Bosch 0445120097 or 0445120144. Can I use this injector? Yes. Bosch 0445120237 is the current number that replaces the earlier Bosch numbers 0445120097 and 0445120144, so an engine originally built with one of those codes is served by this injector.

What are 0986435555 and 0986435726? Those are the Bosch Exchange (remanufactured) references for this injector. They are listed so you can identify a remanufactured unit you removed from the engine. The injector on this page is a genuine new Bosch part.

Does this injector have to be coded to the ECU after fitting? No. This injector has no individual injector accuracy code, so there is no calibration code to write to the engine control unit after installation. The engine still has to be bled and the fuel system purged of air in line with the manufacturer's procedure.

Should I replace all six injectors at the same time? Replacing the complete set is what we recommend. All six injectors have run the same hours and are worn to a similar degree, so fitting one new injector next to five worn ones leaves the cylinders working unevenly, and the new injector then runs under a different load than the rest and wears faster. That is why a partial replacement often ends in a second repair. Have the full set tested first, then replace what the test shows.

What is the difference between the QSL9, ISL9, L9 and PX-9 engine names? They are Cummins naming variants of the same 8.9L six-cylinder family: QSL9 for off-highway and industrial units, ISL9 and L9 for on-highway trucks and buses, and PX-9 for the Paccar-badged version fitted to Kenworth and Peterbilt. Identification still has to be made by injector or OE number, because not every build of this family uses the same injector.

What comes in the box? One Bosch 0445120237 injector in the original Bosch packaging, one injector body O-ring and one nozzle sealing washer. High-pressure lines, connector tubes and hold-down clamps are not included.

Do you ship worldwide? Yes, we ship worldwide.

Common symptoms of a failing common rail injector on an 8.9L engine

A worn or leaking 0445120237 injector typically shows up as extended cranking or a hard start on a cold engine, a rough or hunting idle, a cylinder-specific misfire, loss of power under load with the tractor or truck pulling badly, black or white smoke, a higher than normal fuel consumption, and a noticeably rattling engine on one bank. Excessive internal leak-off also drags rail pressure down, which sets low-rail-pressure diagnostic trouble codes even though the pump is healthy. A professional fuel-system test must be carried out before replacing any parts, including a leak-off (return flow) test on each injector and a rail-pressure test, to confirm the injector is the actual cause of the fault.

Installation and system check

The fuel supply system is checked for contamination before any injector is fitted, whatever caused the original fault. Start at the fuel filter and its housing, because that is where debris and sticky deposits show first.

Affected components are cleaned or replaced: the tank, the supply and return lines, the filter housing and filters, the rail and the high-pressure pump. High-pressure lines and injector connector tubes are replaced, not cleaned, because their bores cannot be reliably decontaminated. The system is then flushed, fitted with new filters and bled in line with the manufacturer's procedure.

The cause on these engines is almost always poor or contaminated diesel: badly stored fuel, tanks that are not cleaned periodically, or contaminated containers used for refuelling. On agricultural machines with farm-yard bulk tanks and long standing periods, water and sludge in the tank are the normal starting point of an injector failure.

When fitting, use the new nozzle sealing washer and the new body O-ring supplied with the injector, clean the injector bore in the cylinder head, and tighten the hold-down clamp and the high-pressure line to the manufacturer's torque figures. An injector fitted into a system that has not been decontaminated fails again within a short service period, and that failure is not covered by the warranty.

Before the new injector is fitted, the fuel supply system must be checked for contamination. Rust, water, sludge or varnish-like deposits, metallic debris or any other contaminant left in the tank, supply and return lines, filter housing or rail will damage the new injector within a short service period, and that damage is not covered by the warranty. Inspect and decontaminate the system, renew the filters and confirm that the fuel is clean before installation.