Replacing the Valve Stem Oil Seals

GENERAL INFORMATION

Excessive oil consumption may be caused by worn valve stem oil seals. The valve stem oil seals can be removed without removing the cylinder head, but a special tool is required. If the special tool is not available, the cylinder head must be removed.

Removal

PROCEDURE

1. Remove the cylinder head.

2. Remove the valves.

3. Remove the valve stem oil seals. Pliers are required for removal. For engines with bucket tappets, workshops use special tools. Old seals usually sit very tightly, so a slide hammer should be used for removal whenever possible.

Caution: Do not use a screwdriver for removal, as this may damage the seal seating surface. Installation

PROCEDURE

1. Before installing the valves, inspect the valve guides and, if necessary, resurface or lap the valve seats.

2. Lightly lubricate the new valve stem seals (3) and install them onto the valve guides (4).

3. Install the seal with the correct installer (1) until it stops against the valve spring retainer (2). Dimension 5 must be: 15.2 mm.

Warning If the special installer is not available, install the seal using a hammer and a suitable tube. The tube must have the same diameter as the seal and must not have sharp edges.

4. Install the valve springs with the upper and lower spring seats and compress them. The narrow end of the spring must face the cylinder head.

5. Install the valve collets, then release the valve spring compressor.

6. Replace all valve stem seals in the same way.

7. Install the valves.

8. Install the cylinder head.