Boost Doc Crankshaft & Flywheel Lock Tool for 10mm / 12mm Bolts BDCLTV2

Hold the crankshaft in place without fighting the engine every time you need to remove a stubborn crank pulley, harmonic balancer, flywheel or clutch. This lock tool from Boost Doc bolts to the engine and engages the flywheel, giving you a solid way to stop the crankshaft from turning while you loosen or tighten the hardware.

It works with many Nissan, Toyota, Subaru, Mitsubishi, BMW, Ford and Fiat engines that use a compatible 10mm or 12mm mounting point. This is especially useful during engine builds, timing service, clutch changes and flywheel installation when the engine may already be out of the car.

Fitment Information

• Fits many engines with an accessible flywheel ring gear and compatible 10mm or 12mm threaded mounting point
• Nissan RB engines, including popular RB20DET, RB25 RB25DET, RB25DET NEO, RB26  RB26DETT and RB30 applications
• Nissan CA engines, including popular CA18DET applications
• Nissan KA engines, including popular KA24E and KA24DE applications
• Nissan VG engines, including popular VG30DE and VG30DETT applications
• Toyota JZ engines, including popular 1JZ-GE, 1JZ-GTE, 2JZ-GE and 2JZ-GTE applications
• Mitsubishi 6G72 engines, including popular 3000GT and Dodge Stealth applications
• Subaru EJ-series engines, including popular EJ20, EJ22 and EJ25 applications such as the EJ205, EJ207, EJ255 and EJ257
• BMW inline-six engines, including popular M50, M52, M54, S50, S52, S54, N54 and N55 applications
• Boost Doc also lists compatibility with select Ford and Fiat engines

Fitment Notes

• The engines above are popular examples of applications to check. Boost Doc does not provide a complete engine-code fitment list, so compatibility must be confirmed from the flywheel ring gear, mounting point and available clearance.
• This is a multi-application engine service tool, not a vehicle-specific tool.
• Compatibility depends on the flywheel ring gear, available mounting point and clearance around the bellhousing or engine block.
• Access to the flywheel or flexplate ring gear is required.
• Confirm whether your application uses a compatible 10mm or 12mm mounting point before ordering.
• Engines with an aftermarket transmission, adapter plate, bellhousing or flywheel should be checked carefully because the mounting position may differ from the original setup.
• The tool must engage the ring gear securely without damaging the teeth or contacting surrounding components.

Common Uses

• Removing or installing a crankshaft pulley bolt
• Removing or installing a harmonic balancer
• Removing or installing a flywheel
• Removing or installing a clutch assembly
• Holding the crankshaft during engine assembly
• Holding the crankshaft during timing-system service

Specs & Features

• Locks against the flywheel ring gear to stop crankshaft rotation
• Fits compatible 10mm and 12mm mounting-bolt applications
• Allows one person to loosen or tighten crankshaft and flywheel hardware
• Useful with the engine installed or mounted on a compatible engine stand
• Compact design is easy to keep with other engine-building tools
• Part Number: BDCLTV2

What's Included

• Boost Doc flywheel lock tool
• 10mm mounting bolt
• Bolt sleeve

How It Works

The tool bolts to a compatible mounting point near the flywheel and rests against the ring-gear teeth. Once it is correctly positioned, the flywheel cannot rotate, which keeps the crankshaft from turning while you work on the crank pulley, harmonic balancer, clutch or flywheel.

Using the Tool

• Confirm that the mounting location uses a compatible 10mm or 12mm bolt.
• Position the tool so it fully engages the flywheel ring gear.
• Make sure the tool is sitting flat and cannot slip when torque is applied.
• Thread the mounting bolt in by hand to avoid damaging the engine threads.
• Tighten the mounting bolt enough to hold the tool securely.
• Apply torque gradually while watching the tool and ring gear for movement.
• Remove the lock tool before attempting to rotate or start the engine.

Pairs Well With

• ACT Clutch Kit for Nissan Skyline R32 / R33 RB20DET or RB25DET – Hold the RB flywheel in place while removing the old clutch and torquing the replacement clutch and flywheel hardware.
• ACT Streetlite Flywheel for Toyota Supra A80 – Use the lock tool to keep the 2JZ crankshaft from rotating during flywheel removal and installation.
• ARK Chromoly Flywheel for Nissan 240SX S13 / S14 – Makes a good addition to a KA clutch job where the flywheel and crankshaft need to be held securely during installation.

About Boost Doc

Boost Doc is an Australian company that makes practical tools and engine parts with a strong focus on Nissan RB builds. Its lineup includes engine-stand adapters, lifting hardware, crankshaft tools and other parts designed to make engine assembly and maintenance easier.