Installation of TDC is needed when replacing the timing belt and for other repair work on the engine
On K7J, K7M and K4M engines, the cylinders are counted from the flywheel.
Setting the top dead center (TDC) of the first cylinder of the K7J and K7M engines
When setting the marks, it must be borne in mind that the camshaft makes one revolution in four engine strokes, and the crankshaft makes two revolutions.
Therefore, when aligning the marks on the crankshaft pulley and the hole on the cylinder block, both the first cylinder and the fourth can be located at TDC.
It is necessary to set the TDC according to the mark on the camshaft pulley (when installed according to the marks on the crankshaft pulley, the piston of either the 1st or 4th cylinder may be in this position).
After that, be sure to make sure that the marks on the crankshaft toothed pulley match (with the accessory drive pulley removed).
If the marks on the crankshaft pulley do not match, then the valve timing is broken (the piston of the 1st cylinder is not set at TDC). In this case, it is necessary to remove the camshaft drive belt and turn the crankshaft until the marks are aligned.
The crankshaft is turned to check the coincidence of the marks for the bolt attaching the accessory drive pulley to it, removing the upper part of the engine's right mudguard to access it.
In addition, you can do this in the following ways (especially when adjusting the clearances in the valve drive, when control by marks on the crankshaft toothed pulley is not needed):
- turn on any gear (preferably IV) and slowly drive the car until the marks are aligned;
- take out one front wheel, engage any gear and then turn the suspended wheel until the marks are aligned.
The mark on the camshaft pulley must match the mark on the cylinder head cover, which is shaped like the Dachia logo.
And on the timing belt there is also a mark with paint, which must also match the marks.
The mark on the crankshaft toothed pulley must be aligned with the mark on the cylinder block.
This mark can only be seen after removing the accessory drive pulley.
To install TDC, remove the right front wheel.
We remove the upper part of the engine mudguard (see the article - How to remove the protection and mudguards of the Renault Sandero engine)
We remove the accessory drive belt (see the article - Checking and replacing the accessory drive belt Renault Sandero)
Remove the right suspension support of the power unit
We unscrew the five bolts securing the upper timing belt cover
Remove the cover
We turn the crankshaft clockwise by the bolt of the auxiliary unit drive pulley until the marks on the camshaft pulley and the cylinder head cover are aligned
Then we loosen the tightening and finally unscrew the pulley bolt
Remove the pulley
Unscrew the three bolts securing the lower timing belt cover
Remove the cover
It is not necessary to remove the bottom cover when checking the valve timing.
You only need to remove it if you need to replace the belt or rearrange it.
We check the coincidence of the marks on the camshaft pulley and on the cylinder head cover
Installing TDC on a K4M engine
To complete the work, you will need tools: socket head 13, 15, 18, wrench 13, screwdrivers, Torx E14 wrench;
- clamp for installing TDC;
- camshaft lock.
If these clamps are not available, you can make them from sketches:
Removing the right front wheel
Remove the upper part of the right engine mudguard (see the article - How to remove the protection and mudguards of the Renault Sandero engine)
We remove the accessory drive belt (article - Checking and replacing the accessory drive belt Renault Sandero)
We remove the right support of the suspension of the power unit
With a 13 head, unscrew three bolts and two nuts securing the upper timing drive cover
Remove the top cover of the timing mechanism
We rotate the crankshaft clockwise by the bolt of the accessory drive pulley
We set marks on the camshaft pulleys with the Renault logo so that they do not slightly reach the top point
Using the Torx E14 wrench, unscrew the hole plug for installing the TDC position lock (Figure 9, shown on the removed engine)
The plug is located to the left of the flywheel in the cylinder block at the level of the 1st cylinder
Screw the TDC position lock into the hole
We turn the crankshaft all the way
Unfasten the rubber clamp for the air intake
Disconnect the air intake from the air filter housing
Take off the sleeve
We pierce the camshaft plugs with a flat screwdriver
We press out the camshaft plugs
With the correct installation of the piston of the 1st cylinder in the TDC position of the compression stroke, the grooves at the ends of the camshafts should occupy a horizontal position and be displaced downward relative to the camshaft axis.
We fix the camshafts in this position with a camshaft lock.