The valve stem seals can be replaced without removing the cylinder head from the engine.
You will need: all the tools needed to remove the cylinder head cover (see «Replacing the cylinder head cover gasket»), as well as the key «at 12», tweezers (or magnetized screwdriver) for extracting crackers from the plates of valve springs...
...a tool for compressing valve springs.
...tick...
...or an inertial oil seal remover. The puller shown has a mandrel on the other end for pressing on the caps. In the absence of such a puller, you will need pliers to remove the caps and a mandrel of a suitable diameter to press them onto the valve guides.
1. Disconnect the wire from the terminal «minus» battery.
2. Remove all spark plugs (see «Replacement and maintenance of spark plugs»).
3. Remove the cylinder head cover (see «Replacing the cylinder head cover gasket»).
4. Set the piston of the 1st cylinder to the TDC position of the compression stroke (see «Setting the piston of the first cylinder to the TDC position of the compression stroke»).
Note. With this position of the crankshaft, the pistons of the 1st and 4th cylinders are at TDC. This makes it possible «dry out» valves of these cylinders without the risk of dropping them into the cylinder.
Note. To set the piston of the 1st cylinder to the TDC position of the compression stroke, the removal of the upper cover of the timing belt is required (to access the timing marks on the camshaft pulley and on the block head), which entails labor-intensive preliminary operations to remove the right suspension support of the power unit. With an accuracy sufficient to set the pistons of the 1st and 4th cylinders to the TDC position when replacing the valve stem seals, the camshaft can be set to the desired position, controlling it visually. When turning the crankshaft, the camshaft must be installed so that the heels of the rocker arms of the drive of both valves of the 1st or 4th cylinder rest on the back of the camshaft cams, and the rocker arms can be moved «rocking» within the gap.
5. Evenly loosening the tightening of the five bolts securing the axis of the rocker arms of the valve drive...
6.... remove the bolts from the holes of the block head and axle...
Note. Please note that the bolts have different head shapes. Install the bolts when reassembling in their original places.
7.... and remove the axle assembly with rocker arms.
Note. If you do not intend to replace the rocker arms, their axle and camshaft, do not remove the rocker arms from the axle in order to install them in their original places during assembly.
8. Install the tool for compressing the valve springs by screwing into one of the holes in the head of the block the bolt securing the axis of the rocker arms and hooking the tool on this bolt.
9. Compress the valve spring with a tool and remove two crackers from the spring plate using tweezers or a magnetized screwdriver. Then remove the fixture.
10. Remove the spring plate...
11.... and valve spring.
Note. The valve spring support washer can not be removed, as it does not interfere with the replacement of the valve stem seal.
12. Press the valve stem seal off the valve guide. To do this, install the collet of the inertial oil seal remover on the cap and sharply hit the collet bushing with the striker. Then just as sharply hit the handle of the device with the striker, thereby compressing the cap from the sleeve.
13. In the absence of an inertial cap remover, remove the cap with a special tong-type remover or pliers, applying force straight up and without turning the cap so as not to damage the valve guide.
Attention! Do not remove the cap by prying it on both sides with screwdrivers. The guide sleeve, on which the cap is put on, is made of cermet, and its edge easily breaks off.
14. Before installing new valve stem seals, we recommend that you remove the springs from them, otherwise the caps can be damaged when they pass through the grooves for crackers on the valves. If the set of new caps includes a plastic mounting sleeve, the springs can not be removed. In this case, put the sleeve on the valve stem.
15. Lubricate the inner surface of the valve stem seal with engine oil and slide the cap along the valve stem to the guide sleeve.
16. Install the mandrel for pressing the cap. With light blows of the striker on the mandrel, press the cap in until it stops. In the absence of a special device, you can choose a cylindrical mandrel of a suitable diameter and press the cap through it with light hammer blows on the mandrel.
Note. As a mandrel, you can use a long head from the tool kit. Choose a head with 12 facets and a chamfer inside the hole so that the contact of the head with the cap is in a solid circle.
17. Remove the guide sleeve from the valve stem or put a spring on the cap if it was removed.
18. Install the spring and valve disc in the reverse order of removal. Install the crackers with the tool so that they fit into the grooves of the valve stem. After installing the crackers, hit the end of the valve with a hammer through the metal rod so that the crackers sit in place.
Warning! If the crackers installed with a warp remain unfixed, when starting the engine «cracked» the valve will fall into the cylinder, resulting in a serious engine failure.
19. Similarly replace valve stem seals of the second valve of the 1st cylinder and two valves of the 4th cylinder.
20. Turn the crankshaft half a turn so that the pistons of the 2nd and 3rd cylinders are at TDC, and replace the valve stem seals of the remaining valves.
21. After installing the axis of the rocker arms of the valves assembly with the rocker arms on the engine, check and, if necessary, adjust the clearances in the valve drive (see «Valve clearance adjustment»).
Note. Bolts of fastening of an axis of yokes tighten evenly the moment of 23 Nm (2.3 kgf·m).
22. Install all removed parts in the reverse order of removal.