We remove the camshafts when repairing the cylinder head, when it is necessary to remove the camshafts
We replace the camshafts if there is increased wear of the journals and camshaft cams during engine operation
We prepare the car for the task and disconnect the negative battery terminal
Remove the cylinder head cover, as indicated in the article "How to replace the Mazda 6 cover and cylinder head gasket"
Remove the gears of the camshafts by tying a chain to them and securing them together with it over the edge of the timing cover
Before removing the bearing caps of the camshafts of the 2.0 and 2.5 liter engine, it is also necessary to remove the phase control solenoid valve by disconnecting the wire block and unscrewing the bolt securing the intake camshaft bearing cap
We unscrew the bolts securing the camshaft bearing caps, and remove the bearing caps
Camshaft bearing caps are numbered
You need to write down their location, depersonalization is prohibited
Lid marks are on the outside of the lids
Remove the camshafts
Inspecting the camshafts
The surfaces of the bearing journals and cams must be undamaged and well polished
If traces of seizing, overheating, deep risks or wear in the form of a cut are found on the working surfaces of the cams, we replace the shafts
In workshops equipped with special tools and fixtures, the radial runout of the camshaft journals can be checked.
If the runout is greater than 0.02 mm or the journals are misaligned, replace the shaft as it cannot be straightened.
Lubricate the camshaft beds with clean engine oil and place the camshafts in them in such a position that neither of the cams rests with the highest part of its toe on the valve lifter shim.
Install the camshaft bearing caps.
Clean the grooves of the cover and the mating surface of the head of the block from the remnants of the old gasket.
We tighten the bolts of the camshaft bearing caps in the order shown in the photo in three stages:
- - evenly tighten the bolts half a turn each until the bearing caps come into contact with the surfaces of the cylinder head;
- - tighten with a torque of 7 Nm (0.7 kgf m);
- - tighten by 45º.
Install the rest of the removed parts in the reverse order of removal.
