5-101.bk Page 25 Friday, March 17, 2006 11:05 AM
200 BENCH PROCEDURES [213 NB] Inlet and Exhaust Valve Removal
VALVE STEM SEALS
Refer to Figure 5-25.
A new valve stem seal was introduced into E7 engine production on 11/1/96, beginning with engine serial number 6S2657. The older valve stem seal has a single sealing lip, while the newstyle seal incorporates a second lip that significantly reduces crankcase blowby. This new seal can easily be identified by the steel retainer band around the top of the seal lip.
1. Attach valve spring keeper remover J 29294-B to cylinder head. 2. Rest tool compression forks (4) on top of upper washer (3) and center forks above valve. 3. Depress tool handle until valve spring is compressed. Remove valve spring washer keys (2) using a magnet (1).
Valve spring keeper remover J 29294-B must be repositioned for each series of valves (two inlet and two exhaust, per cylinder). Drilled and tapped holes are provided for each cylinder.
Refer to Figure 5-26.
To improve seal-to-guide retention, a change was made to the valve guides. The new-style guides have three sharp ridges machined into the upper outside diameter surface (refer to Figure 5-26). The new valve guides were phased into production during the first quarter of 1997.
1 4
3
2
200286a
Figure 5-25 — Valve Spring Keeper Removal 1. Magnet 2. Valve spring washer keys
3. Upper washer 4. Tool compression forks (J 29294-B)
Page 5-25
