2. Piston installation (to her) TDC position is an important honor of many service procedures, such as adjusting valve clearances, removing camshafts and pulleys / timing belt, as well as removing the distributor.
3. Before beginning this procedure, place the transmission in neutral, apply the parking brake or chock the rear wheels. Also shut off the fuel system by relieving fuel pressure (see chapter 4).
4. To bring any piston to the TDC position, rotate the crankshaft using one of the methods described below. When looking at the front of the engine, the normal direction of rotation of the crankshaft is clockwise.
- A) The preferred method is to turn the crankshaft using a socket and ratchet on the bolt on the front end of the crankshaft.
- b) You can also use the remote start switch to save some time. Follow the instructions that come with it. As soon as the piston approaches the TDC position. use the socket head and ratchet as described in the previous paragraph.
- V) If you have an assistant who can pulse the ignition switch to the start position, you can bring the piston to close to TDC without the remote start switch. Make sure your assistant is out of the vehicle with no access to the ignition switch, and use a socket and ratchet to complete the procedure as described in paragraph above (A).
5. Remove the spark plug and install a compression tester in spark plug hole No. 1. It must be a device with a threaded connector and a hose length of at least 15 cm (fig 3.5).
Pic. 3.5. To help locate the TDC, you can insert a compression tester into the #1 spark plug hole
Warning. On a V6 engine, you can check the compression on cylinder #1 without removing the upper intake manifold and throttle body from the engine. If all ignition coils and the fuel pump are disabled, the spark plugs can be left in the cylinder heads (except spark plug for cylinder no. 7).
6. Rotate the crankshaft using one of the methods described above while observing the pressure on the compression gauge. The moment at which the pressure gauge begins to show pressure indicates that the No. 1 cylinder has begun its compression stroke. Continue turning the crankshaft and align the mark on the crankshaft pulley with the mark «ABOUT» on the timing plate (pic. 3.6). If you miss the mark, release the pressure and turn the crankshaft two more turns.
Pic. 3.6. Screw the crankshaft until the mark on the pulley aligns with the mark «0» on the timing plate
7. After piston No. 1 is moved to the TDC position on the compression stroke, the TDC position for the remaining cylinders can be determined by turning the crankshaft 120° (⅓ turnover) at a time and following the order of the cylinders (talk to Specifications).