Align the piston number 1 (in firing order) at its bottom most position.
Top dead center on an engine is defined as when the piston is farthest from the crankshaft. Bottom dead center is when the piston is closest to the crankshaft on the engine.
The top dead center is when the piston has reached its peak and can go no farther up, it has reached its summit. The bottom dead center is when the piston is at its lowest point.
Bottom dead centre. BDC
The distance from Top Dead Center to Bottom Dead Center of piston movement.
Measure the distance a piston travels from bottom dead center to top dead center.
The distance from Top Dead Center to Bottom Dead Center of piston movement.
TDC means top dead center BDC means bottom dead center
Bottom dead center. It is when the piston is at the very bottom of it's travel.
BDC means Bottom Dead Center
A Stroke of a crankshaft is determined by the "Distance" between the "center-point (CP) of Crankshaft(CRKST) to the center-point(CP) of Rod Journal(RJ)" where the big end of the Connecting Rod(CR) goes. the small end of the CR attaches to the Piston(PN) via a wrist pin. If that "Distance" is 2 inches(2.00) <a half-stroke> multiply by 2 = 4inches or a 4.00 Stroke, and this amount of full stroke usually gives good truck torque at low to mid RPM. Now when the PN is both at Top Dead Center(TDC) or Bottom Dead Center(BDC), the The Bore of a cylinder where the piston rides up & down(stroke) is measured by diameter, say 3-1/2(3.5) inches divided by 2 = 1-3/4(1.75) inches, is the center of your Bore and that lines up directly with the center-point of your CRKST, or a Center-line crankshaft.
The stroke of an engine is the distance the piston travels within the cylinder from bottom dead centre to top dead centre. This is governed by the throw of the crankshaft.
If the crankshaft sensor is dead the engine will not start