Granatan TDC Whistle Tool — Top Dead Center Compression Indicator 27" Hose, Dual-Threaded 14/18mm

Granatan Top Dead Center Whistle Tool 8016MRG is a hand-installable TDC compression indicator that uses a whistle sound to identify the piston’s compression stroke so you can set timing and perform valve or distributor work without removing the head.

This compact, workshop-ready top dead center tool pairs a flexible 27" rubber hose with a metal dual-threaded fitting to fit common spark plug ports. Designed for gasoline engines, the whistle eliminates the need to peer into a cylinder by audibly signaling peak compression. It’s lightweight, durable, and built to hold up to routine garage or roadside servicing—ideal for mechanics and DIYers needing a fast, reliable way to locate TDC during timing, valve adjustment, or leak-down procedures.

How does the Granatan whistle tell me when the piston is at top dead center?

The whistle converts compression pulses into a clear audible tone when the piston reaches the compression stroke near top dead center. As you crank the engine, air forced through the hose produces a whistle that peaks at the moment of highest compression, giving an unmistakable cue without visual inspection.

• Audible peak indicates compression stroke and approximate TDC.
• 27" flexible hose lets you stand clear of moving parts while listening.
• Simple hand-threaded installation into spark plug holes makes use quick.

Will this fit my engine and how do I install it?

The dual-threaded metal fitting is made to engage both 14 mm and 18 mm spark plug ports, covering a wide range of cars, trucks, motorcycles and small gasoline engines. Installation is tool-free: thread the fitting into the spark plug hole by hand, route the hose to a safe listening position, and crank the engine slowly until the whistle peaks.

• Dual-threaded metal fitting fits 14 mm and 18 mm spark plug threads.
• Not compatible with diesel engines—designed for gasoline spark-ignited engines only.
• Hand-tighten for a gas-tight seal; no adapters required in most applications.

What maintenance and workshop tasks does this tool support?

Use the Granatan TDC whistle during distributor alignment, ignition timing, valve lash adjustments, timing belt or chain checks, and preliminary cylinder leak-down diagnostics. The audible indication reduces the need to remove the spark plug or visually inspect the piston position, speeding routine procedures.

• Distributor installation and static timing setup.
• Valve clearance checks and setting at TDC on the compression stroke.
• Timing belt or chain verification and basic leak-down assistance.

How durable and safe is the 8016MRG for shop use?

The tool combines a metal fitting with a resilient 27" rubber hose to resist bending, oil exposure, and normal workshop wear. Its flexible hose reduces strain on the fitting and allows comfortable positioning in tight engine bays, while hand installation keeps you away from hot or moving components.

• Metal dual-threaded fitting for repeated use and reliable sealing.
• Long, flexible rubber hose for positioning and operator safety.
• Compact design stores easily in a tool roll or toolbox.

Who is this for: The Granatan Top Dead Center Whistle Tool 8016MRG is aimed at home mechanics, professional technicians, and motorcyclists who work on gasoline engines and want a quick, audible method to find compression stroke TDC. It’s especially helpful when you need a fast setup for distributor timing, valve adjustments, or pre-leak-down checks, and for anyone who prefers hand-installable, low-cost diagnostic aids that don’t require special tools.