Genuine Mazda 1.8L / 2.0L Inlet Valve • LF01-12-111

Genuine Mazda LF01-12-111 1.8L / 2.0L Inlet Valve

Replacement Genuine Mazda inlet valve for Mazda MX-5 Mk3, Mk3.5 and Mk3.75 / NC models fitted with 1.8L L8-DE or 2.0L LF-VE petrol engines from 2005 to 2015 listed in the compatibility table.

The inlet valve—also known as an intake valve—is installed within the cylinder head and controls the flow of the incoming air-and-fuel charge from the inlet port into the combustion chamber. It is operated by the inlet camshaft and associated valvetrain components.

During the intake stroke, the valve opens to allow the cylinder to fill. It then closes against the machined valve seat during compression and combustion. Accurate valve-stem dimensions, head profile and sealing-face geometry are essential for maintaining compression, airflow and correct valvetrain operation.

This listing supplies one Genuine Mazda inlet valve. Both the 1.8L L8-DE and 2.0L LF-VE engines use eight inlet valves, so eight are required when replacing the complete inlet-valve set. The inlet and exhaust valves are different components and must not be interchanged.

Replacement may be required where the original valve is bent, burned, cracked, pitted, excessively worn or no longer seals correctly against the valve seat. Possible symptoms include low compression, misfiring, poor idle quality, reduced engine power, increased emissions or leakage identified during cylinder-head testing.

• Part type: Inlet valve / intake valve
• Primary use: Controls the intake charge entering the combustion chamber
• Location: Cylinder head / inlet side of the valvetrain
• Vehicle application: Mazda MX-5 Mk3, Mk3.5 and Mk3.75 / NC
• Engine applications: 1.8L L8-DE and 2.0L LF-VE petrol engines
• Quantity per cylinder: Two inlet valves
• Quantity per engine: Eight inlet valves
• Quantity supplied: One inlet valve
• Brand: Genuine Mazda
• Part No.: LF01-12-111
• Also referenced as: LF0112111
• Important note: Inlet and exhaust valves are separate components and are not interchangeable

Fitment advice: Confirm whether the vehicle is fitted with the original Mazda 1.8L L8-DE or 2.0L LF-VE engine and compare the original valve with the replacement before assembly. Cylinder heads previously rebuilt with non-standard valves, guides, seats or upgraded valvetrain components should be measured carefully before parts are installed.

Other items to consider: When changing this part, you may also want to consider purchasing valve stem oil seals, valve guides, valve springs, upper spring retainers, valve collets, exhaust valves, valve-clearance adjustment buckets, a cam-cover gasket, cylinder-head gasket, head bolts and timing-chain components.

Useful tools / consumables: Valve spring compressor, valve-guide measuring equipment, micrometer, dial gauge, valve-seat testing equipment, valve-lapping tools where appropriate, clean engine assembly lubricant, calibrated torque wrench and Mazda-compatible camshaft and timing tools.

Difficulty guide: DIY Difficulty: Advanced / Engine Reconditioning. Replacement requires cylinder-head and valvetrain dismantling. Valve-guide clearance, valve-seat contact, installed height and sealing must be measured and corrected as necessary before the engine is reassembled.

Why Genuine Mazda? Genuine Mazda inlet valves are manufactured to the intended stem diameter, overall length, valve-head profile, seat angle and material specification. Using the correct OE valve helps retain reliable sealing, correct valvetrain geometry and compatibility with the original Mazda valve guide, seat, spring and retaining components.

What’s in the box: One Genuine Mazda inlet valve, part number LF01-12-111. The valve stem oil seal, spring, upper retainer, collets and other cylinder-head components are not included.

Installation notes: Inspect and measure the valve guide, valve seat and adjoining valvetrain components before installation. Confirm the valve seating pattern and valve-to-guide clearance, and carry out any required cylinder-head machining using suitable specialist equipment. Lubricate the valve stem during assembly, install a new valve stem oil seal and follow the applicable Mazda workshop procedure for valve-clearance checks, camshaft timing and cylinder-head assembly.