8016MRG Top Dead Center Tool, Universal for Top Dead Center Whistle, with 14mm & 18mm Spark Plug Ports, for Distributor Timing & Valve Adjustment

Step 1: Remove spark plug from the cylinder you're working on. Step 2: Hand-thread the whistle into the spark plug hole. Step 3: Rotate crankshaft in normal direction. Step 4: Listen, whistle starts during compression stroke. Step 5: Stop rotating when whistle stops, you've found TDC.

• 【Replaces Part Number】8016MRG, 33650 top dead center tool. Check the part number to confirm the compatibility before purchase.
• 【Dual Specification Compatibility】8016MRG top dead center tool is made of premium materials, features a dual-size threaded fitting that easily installs into both 14mm and 18mm spark plug holes, compatible with most gasoline engines. Not for use on diesel engines.
• 【Precise Positioning】Tool whistles as the piston approaches Top Dead Center (TDC) on the compression stroke and stops whistling when the piston reaches TDC. This makes it easy to pinpoint TDC for ignition timing, valve adjustments, and cylinder diagnostics.
• 【Widely Used】The 8016MRG top dead center tool perfect for distributor installation, individual cylinder valve setting, timing belt or chain inspection, and cylinder leak down testing, essential for mechanics and DIYers alike.
• 【Easy Installation】No tools required, just hand-thread the top dead center whistle into the spark plug port and you're ready to go.