The piston of the 1st cylinder is set to the TDC (top dead center) position of the compression stroke so that when carrying out work related to the removal of the camshaft drive belt, the valve timing is not disturbed.

If the valve timing is disturbed, the engine will not work normally.

Set the TDC of the compression stroke according to the marks on the camshaft pulleys (when setting according to the marks on the flywheel or crankshaft pulley, the piston of either the 1st or 4th cylinder can be in this position).

After that, be sure to check that the marks on the flywheel or on the crankshaft pulley (if the generator drive pulley is removed) match.

If at the same time the mark on the flywheel or the crankshaft pulley does not match, then the installation of the gas distribution phases is violated (the piston of the 1st cylinder is not set to TDC).

In this case, it is necessary to remove the camshaft drive belt and rotate the crankshaft until the marks are aligned.

Required tools: 17" box wrench, 5" hex wrench, Phillips screwdriver.

Since it is inconvenient to turn the crankshaft by the pulley bolt, you can do it in the following ways:

  • 1) turn on any gear (preferably 4th) and slowly drive the car until the marks on the camshaft pulleys match the mark on the rear cover of the camshaft drive belt;
  • 2) engage any gear and hang one of the front wheels.

Then turn the suspended wheel until the mark on the camshaft pulley matches the mark on the rear cover of the camshaft drive belt.

How to set the TDC of a VAZ-21126 engine

On the engine mod. 21126 Marks are made on the camshaft pulleys (protrusions A) and the rear cover of the camshaft drive belt (slots B).

How to set the TDC of a VAZ-21126 engine

In addition, marks are applied to the flywheel (risk) and the scale of the clutch housing rear shield (triangular notch). For clarity, the gearbox has been removed.

How to set the TDC of a VAZ-21126 engine

In addition, all engines have marks on the crankshaft sprocket (dot) and the oil pump cover (triangular cutout).

These marks are only visible when the alternator drive pulley is removed.

How to set the TDC of a VAZ-21126 engine

Disconnect the wire from the negative terminal of battery2.

Using a Phillips screwdriver, remove one screw securing the right mudguard to the fender liner

How to set the TDC of a VAZ-21126 engine

Remove the two screws securing it to the body

How to set the TDC of a VAZ-21126 engine

Remove the mudguard

How to set the TDC of a VAZ-21126 engine

Open the hood and use a 5mm hex wrench to remove the five bolts on the top cover of the timing belt.

How to set the TDC of a VAZ-21126 engine

Remove the lid.

How to set the TDC of a VAZ-21126 engine

Using a 17 spanner, turn the crankshaft by the bolt securing the alternator drive pulley to it until the marks on the camshaft pulleys and the rear cover match.

How to set the TDC of a VAZ-21126 engine

Remove the plug from the hole in the clutch housing and check the alignment of the marks on the flywheel.

After carrying out work related to the installation of the TDC, you need to assemble all the parts in the reverse order