The CAT 3064 engine has powered thousands of Caterpillar excavators across job sites worldwide since the mid-1990s. This guide is for owners, operators, and mechanics of Caterpillar 311 and 312 series excavators, as well as anyone considering a rebuild or maintenance of the CAT 3064 engine.
- The Caterpillar 3064 is a compact, durable 4-cylinder diesel engine.
- It uses a direct fuel injection system.
- The CAT 3064 engine is commonly used in compact and mid-sized Caterpillar construction machinery.
If you own or maintain a Cat 311 or 312 series machine, there's a good chance this is the engine under your hood. In this guide, you'll find the specs you need, the machines it fits, and what's involved when it's time for a rebuild. Read on for everything you need to know about keeping your 3064 running strong.
Key Takeaways
- The CAT 3064 is a compact, durable 4-cylinder diesel engine with a displacement of approximately 3.9 to 4.25 liters, used mainly in Cat 311 and 312 series excavators and similar compact to mid-sized equipment.
- In its turbocharged 3064T form, the engine delivers between 72 and 95 horsepower (roughly 67 kW) at about 1,950 rpm, with peak torque of approximately 274 lb-ft - built for low-end torque and reliability, not high RPM.
- Fab Heavy Parts provides aftermarket rebuild kits, long blocks, and key components for the 3064 engine and 3064T variants, helping customers extend the life of proven machines.
- Knowing your engine serial number (such as a 6LK prefix) is required for matching the right parts to your specific 3064 engine configuration.
- You'll learn basic specs, common machine fits, maintenance and rebuild options, plus how to choose the right parts and source them with confidence.
Overview of the CAT 3064 Engine
The Caterpillar 3064 is a mid-size, 4-cylinder diesel engine that saw wide use in hydraulic excavators throughout the 1990s and early 2000s. You'll find it in machines like the Cat 311, 311B, 311C, 312, 312B, and 312C. It was manufactured during a time when Caterpillar prioritized mechanical simplicity and job-site toughness over electronics and emissions hardware.
Most 3064 engines used in excavation equipment are turbocharged, carrying the 3064T label. Turbocharging helps maintain power under load - exactly what you need when you're digging, loading, or moving earth hour after hour. The Cat 3064 engine is commonly used in compact and mid-sized Caterpillar construction machinery where a high power-to-weight ratio matters.
The Cat 3064 engine is associated with the Mitsubishi S4K-T engine family, since Caterpillar and Mitsubishi shared design lineage and sometimes manufacturing during this era. Despite that partnership, parts, manuals, and overhaul support are fully available through Caterpillar dealers and quality aftermarket suppliers. The engine is noted for its exceptional durability and longevity, and it features simplified maintenance compared to modern electronically controlled engines. That's a major reason so many of these machines are still running - and still worth rebuilding.
At Fab Heavy Parts, the focus is on reliable aftermarket parts for the 3064 engine, helping owners get more life out of equipment that's already proven itself on the job.
CAT 3064 Engine Specifications & Applications
Understanding the specs of your caterpillar engine matters more than you might think. Accurate information on displacement, power, and bore size helps with troubleshooting, ordering the right parts, and comparing the 3064 to other engines in the Cat lineup.
Core Specifications
Here are the key numbers for the CAT 3064 and 3064T:
- Engine type: 4-stroke, inline 4-cylinder diesel engine
- Displacement: Approximately 3.9 to 4.25 liters (around 259 cubic inches)
- Bore: 102 mm (4.016 inches)
- Stroke: 130 mm (5.118 inches)
- Induction: Turbocharged on 3064T variants; naturally aspirated on some base 3064 models
- Power output: The CAT 3064 engine delivers between 72 and 95 horsepower (about 67 kW at the common 90 HP rating), depending on application and configuration
- Peak torque: Approximately 274 lb-ft, designed for strong low-end pulling power rather than high RPM
- Rated speed: Full load at approximately 1,950 rpm
- Fuel system: Direct fuel injection using a mechanical injection pump - no complex electronics, no sensors to troubleshoot
- Cooling: Liquid-cooled with a heavy-duty cooling system, sized for long hours in hot job-site conditions (coolant capacity around 17.5 liters on equipped machines)
The 3064T's performance profile is built around torque. It won't spin fast, but it will dig, swing, and track with consistent power delivery all shift long.
Common Machine Applications
The 3064 engine was sold in a range of Caterpillar excavators and some industrial equipment:
- Caterpillar 311 Hydraulic Excavator - including the 311B and 311C variants
- Caterpillar 312, 312B, and 312C Hydraulic Excavators - the 312C with 6LK serial prefix uses the 3064T rated at 90 HP
- Caterpillar 313C and 314C LCR - certain markets and configurations
- Industrial and OEM applications - including generator sets and off-road power units where compact, reliable power is needed
Common applications include various Cat excavator models like the Cat 311B and 312C, but the list goes beyond excavators into industrial engines where the 3064T's footprint and reliability make it a practical choice.
Why the Serial Number Matters
Every 3064 engine carries a serial number stamped on a metal data plate, usually found on the side of the block or near the fuel injection pump. The prefix - for example, "6LK" on many 3064T excavator engines - tells you the exact variant and build configuration. You should always check and document this information before ordering any parts, because small differences in bore size, bearing spec, or gasket design can vary across the production run.
The bottom line: the 3064 engine is a proven caterpillar workhorse. When matched with quality components, it's still very much worth rebuilding.
Rebuild Kits, Parts & Support for the CAT 3064
Why Rebuild Instead of Replace?
Most 3064 engines get rebuilt rather than scrapped, and the math makes sense. A full overhaul costs a fraction of a new machine, and it lets you keep using equipment that's already paid for. The Cat 3064 is used in various excavator models that still hold strong resale value, especially in markets where older, mechanically simple machines are preferred.
What's Inside a 3064 Engine Rebuild Kit?
Caterpillar 3064 engine rebuild kits contain four pistons and rings - one set per cylinder - along with a full complement of wear components. Engine overhaul kits for Caterpillar 3064 include multiple components designed to restore the engine to service-ready condition. Here's what a typical kit covers:
- Pistons and piston ring sets - 4 pistons and 4 ring sets, sized to match the 3064's 102 mm bore (std sizing, with oversize options available)
- Piston pins and retainers - 4 complete sets, designed to match OEM clearances for proper fit and minimal play
- Cylinder liners or repair sleeves - 4 semi-finished sleeves that may require honing after installation to restore worn cylinder bores
- Main bearing set and connecting rod bearing set - a complete set covered in the kit at standard sizes, with oversize bearings available for engines with worn crankshaft journals
- Thrust washer set - controls crankshaft end play, a critical detail for engine longevity
- Complete gasket sets - head gasket, rocker cover gaskets, oil pan gaskets, and seals for a full overhaul
Overhaul kits may include repair sleeves and gaskets as standard contents. The overhaul kit also includes a main bearing set and rod bearing set to address bottom-end wear.
In-Frame vs. Out-of-Frame Kits
Not every rebuild requires pulling the engine entirely. Here's the difference:
- In-frame kits are used when the engine stays in the machine frame. This approach works when bore wear is moderate and the bottom end is still in good shape. It's less labor, less downtime, and lower cost.
- Out-of-frame or full overhaul kits are required when the engine needs to come out for block machining, crankshaft regrinding, and a complete inspection. This is the route for high-hour engines showing serious wear or low compression across cylinders.
Long Blocks and Drop-In Replacements
Fab Heavy Parts can also supply 3064 engine long blocks and rebuilt 3064T industrial engines. These are suited for machines like the Cat 311B, 311C, 312B, and 312C where a drop-in replacement saves time on the rebuild process.
How Fab Heavy Parts Supports Customers
Getting the right parts for your exact engine doesn't have to be complicated. Here's how Fab Heavy Parts helps:
- Serial number matching - Help identifying your exact 3064 engine variant using your serial number and arrangement number, so nothing ships that doesn't fit
- Kit selection guidance - Advice on choosing between in-frame vs. out-of-frame kits based on your machine hours, oil consumption trends, and compression test results
- Shipping and availability - Access to both new surplus and remanufactured Caterpillar 3064T engines where available, with shipping across the United States and to international locations
Customers can review available inventory and request a quote directly through the website or by phone.
Best Practices for a Successful 3064 Rebuild
Dropping in new pistons and rings isn't enough on its own. To get the most from your rebuild:
- Inspect the crankshaft journals and camshaft lobes. Don't just accept that the bottom end is fine - measure it.
- Replace wear items while the engine is already apart. Oil pump, water pump, hoses, belts, thermostat, and injectors should all be evaluated and replaced if needed. This is not the time to skip preventive work.
- Clean and pressure-test the cooling system. A fresh engine overheating on its first day back in service is a costly mistake. The CAT 3064 is liquid-cooled to maintain optimal operating temperatures, but the cooling system has to actually work.
- Source quality parts from a reputable supplier. Aftermarket kits vary widely in material quality and machining tolerances. Choose a source you trust.
FAQ
Q1: How do I find the serial number on my CAT 3064 engine?
A1: The serial number is usually found on a metal data plate on the side of the engine block or near the fuel injection pump. It might also be in your machine’s service records or original documents. Be sure to note the full serial number, including the prefix (like 6LK), before ordering parts. This ensures you get the correct components. If the plate is damaged or hard to read, a dealer or mechanic can help locate it using other markings on the engine.
Q2: What are common signs that my 3064 engine needs an overhaul?
A2: Watch for these key symptoms:
- Difficulty starting, especially when hot
- Blue or white smoke from the exhaust, indicating oil burning
- Increasing oil use between services
- Low compression in multiple cylinders
- Loss of power or trouble maintaining RPM under load
- Metal debris found in the oil filter
If you notice two or more of these signs, scheduling a full or in-frame rebuild is usually more cost-effective than repeated repairs that won't fix the root wear.
Q3: Can I upgrade from a 3064 to a different Caterpillar engine model?
A3: Custom repowers are possible, but most Cat 311 and 312 excavators are built for the 3064 and 3064T engine size, mounts, and power. Switching to a different engine usually requires costly fabrication, wiring, and hydraulic changes. For most owners, rebuilding or replacing with another 3064 or 3064T long block is simpler and keeps original performance. Contact Fab Heavy Parts to discuss your machine before deciding.
Q4: How long does a properly rebuilt CAT 3064 engine last?
A4: With quality parts, clean fluids, and regular maintenance, a rebuilt 3064 engine can run several thousand hours before major work is needed. Actual lifespan depends on conditions like dust, heat, load, and cooling system care. Following Caterpillar's maintenance schedule for oil, filters, and fuel system helps maximize engine life after a rebuild.
FAB Heavy Parts: Your Trusted Engine Parts Supplier
Welcome to Fab Heavy Parts' online catalog, your trusted source for quality auto parts and tools. Explore our extensive selection of Replacement Parts for CAT 3064 Engine and more. Avoid delays by securing the parts you need from a reliable supplier who keeps inventory moving. Our expert team is here to provide personalized support, ensuring you get the right parts. Reach out today to stay ahead and keep your operations seamless!