Easy lifehacks

# How to tell TDC on compression vs exhaust stroke?

## How to tell TDC on compression vs exhaust stroke?

If spark on #1 happens when cams display compression stroke, good. If cams display exhaust stroke, remove cams, rotate crank 360 degrees 9. reassemble, remember this lesson for the next one. In case anyone comes across this later. I did the method above and it sparked at both compression and exhaust strokes.

When to set engine to top dead center ( TDC )?

Procedure NOTE When setting the engine to TDC on the compression stroke for cylinder #1, you must realize that the crankshaft rotates twice for every single rotation of the camshaft. So, if you simply set the crankshaft to TDC without looking at the position of the camshaft, you may actually be at TDC on the exhaust stroke for cylinder #1.

What causes the engine to go to TDC?

As the engine is rotated, the piston will force the dowel upward. When the end of the dowel is at its highest point, the engine is at TDC for the #1 cylinder.

### Where does the crankshaft go when setting to TDC?

So, if you simply set the crankshaft to TDC without looking at the position of the camshaft, you may actually be at TDC on the exhaust stroke for cylinder #1.

When to set the engine to TDC on the exhaust stroke?

NOTE When setting the engine to TDC on the compression stroke for cylinder #1, you must realize that the crankshaft rotates twice for every single rotation of the camshaft. So, if you simply set the crankshaft to TDC without looking at the position of the camshaft, you may actually be at TDC on the exhaust stroke for cylinder #1.

Procedure NOTE When setting the engine to TDC on the compression stroke for cylinder #1, you must realize that the crankshaft rotates twice for every single rotation of the camshaft. So, if you simply set the crankshaft to TDC without looking at the position of the camshaft, you may actually be at TDC on the exhaust stroke for cylinder #1.

When to use TDC between compression and power strokes?

During approach to (TDC) between compression and power strokes when both valves are closed; there will be pressure that will push your thumb off of the hose to allow air to escape. When air stops blowing out it is fairly near (TDC) on the compression stroke. Move on to STEP FOUR. Use a vacuum/pressure gauge. Hook up the gauge to your hose.

So, if you simply set the crankshaft to TDC without looking at the position of the camshaft, you may actually be at TDC on the exhaust stroke for cylinder #1.

Ruth Doyle