Product Overview

The 2873K632 is a heavy-duty starter motor delivering 12V output at 3.2KW with a 10-tooth drive gear, engineered for CATERPILLAR (C4.4), PERKINS (1106C, 1106D), TEREX and CLARK equipment powered by the 1106 engine family. This unit, cross-numbered as 2873K532 and 3586847, matches the original starting-system specification for the Caterpillar/Perkins engine platform.

Fitted with reduction-gear drive design, this brand-new engine starter is stocked in-house with a 1-year warranty and 10-day dispatch lead-time. The factory-correct 3.2KW rating ensures reliable cold and hot cranking of the Cat C4.4 and Perkins 1106 diesel engines.

Key physical specs: net weight 8.2 kg, overall dimensions 340 x 200 x 155 mm, supplied inside neutral kraft inner carton. Gross weight is not stated on the product page.

The Caterpillar and Perkins 1106 Engine Platform and 12V Starting System

Caterpillar C4.4 and Perkins 1106C/1106D engines run standard 12V starting systems with factory-spec starter motors, also used in TEREX and CLARK equipment. The starter motor numbering spans the Perkins OE numbers (2873K632, 2873K532, 2873K621, 2873K631), the Caterpillar numbers (3586847, 11131780, 91-19-2512), the Lester numbers and multiple aftermarket series, all referring to the same starting-system family.

It is critical to verify the drive-gear tooth count on your old starter: this unit uses a 10-tooth drive gear. Starters with a different tooth count or mounting pattern are not interchangeable with this unit. A starter with the wrong tooth count will not engage properly with the flywheel ring gear.

The 12V 3.2KW rating matches the original starting-system specification. Confirm the mounting flange pattern, terminal positions and bolt spacing against your original starter before ordering. The starter mounting interfaces and control wire interfaces of 1106C/1106D/C4.4 engines from different brands may vary; never mix starters across different brands. Always cross-check the OE numbers stamped on your old unit, including the 2873K632 family, before placing an order.

Technical Specifications

Compatibility and Cross Reference

This starter motor fits CATERPILLAR (C4.4), PERKINS (1106C, 1106D), TEREX and CLARK equipment powered by the 1106 engine family. Do not rely solely on the brand name for fitment validation; always compare the original part number, mounting holes, gear teeth and connector configuration before ordering.

Multiple Caterpillar, Perkins, Lester and aftermarket OE numbers appear across production batches and regional market specifications for this same starter motor family. If your original unit bears one of the listed cross-reference numbers, 2873K632 serves as a direct drop-in replacement.

What to Look for in a Replacement

Follow these five verification steps before placing your order to avoid wrong-part returns:

• 1. Check the voltage and power label on your old starter: confirm it is rated for 12V 3.2KW. Other ratings are not interchangeable.

• 2. Count the drive-gear teeth: this unit uses 10T (10-tooth). Starters with a different tooth count, including 8T or 9T units, are incompatible.

• 3. Confirm the platform is a Cat C4.4 or Perkins 1106C/1106D engine family used in Caterpillar, Perkins, Terex or Clark equipment. Other engines may use different starter assemblies.

• 4. Compare the mounting holes, flange pattern and connector configuration with your original starter, and match OE numbers including the 2873K632 family.

• 5. Weight cross-check: genuine matching unit weighs approximately 8.2 kg net; significant weight difference indicates wrong assembly.

Application Scenarios

• Construction machinery repair shops servicing Caterpillar, Perkins, Terex and Clark equipment with 1106 engine family.

• Industrial equipment maintenance teams maintaining Cat C4.4 and Perkins 1106 generator sets and material-handling machinery.

• Auto parts exporters and distributors stocking heavy-duty starting-system components for the Cat/Perkins engine market.

• Used heavy equipment traders refurbishing pre-owned Caterpillar, Perkins, Terex and Clark machinery for global secondary markets.

• Cost-conscious buyers looking for a reliable new starter motor at a competitive price.

FAQ

Q: Which engines does this starter fit?
A: It fits CATERPILLAR (C4.4), PERKINS (1106C, 1106D), TEREX and CLARK equipment powered by the 1106 engine family. Confirm your engine model and OE number before ordering.

Q: My old starter shows OE number 2873K532 or 3586847, will 2873K632 work?
A: Yes. These numbers belong to the same starter motor family for the Cat/Perkins platform, differing only by production revision and market specification. It serves as a direct replacement.

Q: Can I fit this starter onto other engine brands?
A: No. The starter mounting interfaces and control wire interfaces of 1106C/1106D/C4.4 engines from different brands may vary. Confirm your engine model before ordering.

Q: What is the correct operation after installation?
A: The engine should crank briskly and consistently on cold and hot starts. If the starter spins but the engine does not crank, check the drive-gear engagement and ring gear condition.

Q: What is the correct meshing clearance for the drive gear?
A: The standard meshing clearance between the drive gear and the flywheel ring gear is 0.2-0.5mm (refer to the engine OEM manual for specific values). Adjust by changing the mounting gasket thickness if required.

Q: What is your warranty and lead-time?
A: Goods are in stock with a 10-day dispatch lead-time. A 1-year warranty applies from installation date; warranty excludes damage caused by mis-installation, incorrect wiring, water ingress, short circuit or physical damage.

In Practice

For technicians working on Cat C4.4 and Perkins 1106C/1106D engines: Disconnect the negative battery cable first to prevent short circuits during installation, and ensure the engine is in a cold state (at least 1 hour after shutdown) to avoid high-temperature scalds. If the starter installation position is confined, set up a stable maintenance platform and wear anti-slip gloves.

Clean the starter mounting flange surface on the engine flywheel housing to remove oil stains, rust and residual sealant, and clean the starter flange contact surface to ensure a tight fit without gaps. Apply a small amount of anti-seize compound (e.g., copper grease) to the threads of the mounting bolts to prevent rust and seizure during future disassembly; do not apply excessive amounts to avoid oil infiltration into the starter interior.

Align the drive gear end of the starter with the guide hole on the flywheel housing, slowly push it into the installation position, and ensure the correct meshing position between the drive gear and the flywheel ring gear. Insert 2-3 mounting bolts and hand-tighten them to a preliminary fixed state. Check the meshing clearance between the drive gear and the flywheel ring gear: the standard clearance is 0.2-0.5mm (refer to the engine OEM manual for specific values). If the clearance is not up to standard, correct it by adjusting the thickness of the starter mounting gasket (thicker gaskets increase clearance, thinner gaskets reduce clearance); use only OEM-spec gaskets, do not substitute with homemade metal sheets.

After the clearance is adjusted, use a torque wrench to tighten the mounting bolts in a criss-cross symmetrical sequence to the OEM-recommended torque value of 35-45 N.m (refer to the 1106C/1106D/C4.4 engine manual for exact values); do not directly tighten with an air impact wrench. Connect the starter main power terminal: fasten the positive battery cable connector to the thick terminal post, add a flat washer and a spring washer, and tighten the nut to 15-20 N.m. Connect the control circuit: link the thin terminal post of the solenoid switch to the control wire of the starter relay, ensuring the connection is firm; the polarity of the control circuit varies between different brand vehicles, verify the polarity with a multimeter before installation, and never reverse the control wire connection. Reconnect the negative battery cable and ensure it is securely fastened.

Carry out a no-load test first: turn the ignition switch to the start position, observe whether the starter runs smoothly without abnormal noise or jamming, check that the drive gear extends and retracts normally, and limit each no-load test to no more than 2 seconds. Then perform a loaded test: start the engine and confirm smooth startup; the single startup duration shall not exceed 5 seconds, and the interval between two consecutive startups shall be no less than 30 seconds. If the engine fails to start after three consecutive attempts, stop the test immediately and inspect the meshing clearance, circuit connections or engine faults; do not attempt forced startup. A regular inspection cycle of approximately 500 hours is recommended for heavy-duty operation.

References

Parameters, engine applications and installation specifications are compiled based on the CATERPILLAR C4.4 Engine Disassembly and Assembly Manual (UENR4516-11), PERKINS 1106D Engine Service Manual (SEBU8119-02), PERKINS 1106C/1106D Engine Disassembly and Assembly Manual (Starter Installation Torque Specifications), CATERPILLAR C4.4 Industrial Engine Installation Guide, TEREX Heavy-Duty Equipment Maintenance Manual, CLARK Forklift Engine Component Installation Specification, and the industry standard for automotive electrical system installation (ISO 16000-12:2017), verified against actual machine installation tests and after-sales maintenance experience.

About the Author