Changes

NG 900/9-3 Valve Cover Gasket

589 bytes added, 01:19, 16 November 2009
====Ignition Module (IDM or DIC)====
The plastic cover over the intake manifold and the Ignition Module have to be removed first. The ignition module (IDM, a.k.a. the DIC) is held in place by T30 screws and an electrical connector.
[[file:900_9-3_VC_1.jpg|thumbnail|none|Fig. 1 - Ignition Module (IDM or DIC)]]
====Other Components====
* PCV pipe screw, T-30 torx
* Oil filler tube bracket, 10-mm hex bolts
[[file:900_9-3_VC_3.jpg|thumbnail|none|Fig. 2 - Other Components]]
===Removal===
====Valve Cover Bolts====
The valve cover is attached by 16 T-40 torx bolts. Eleven bolts on the outside of the valve cover, and five on the inside. The bolts are fairly tight, and have to be removed using a small ratchet with a short extension and a T-40 bit holder. Clearance for the bit holder is tight near the PCV pipe and the oil filler tube.
[[file:900_9-3_VC_4.jpg|thumbnail|none|Fig. 3 - Valve Cover]]
====Valve Cover====
The old gasket usually sticks to both the valve cover and the head. It may take a tap with a rubber mallet to break the seal, and some careful prying with a screwdriver before the valve cover comes loose, and can be lifted off. The top of the engine, timing chain, timing gears etc. can now be inspected.
[[file:900_9-3_VC_5.jpg|thumbnail|none|Fig. 4 - Valves]]
===Assembly===
====Gasket Replacement====
The valve cover groove should be cleaned and dried before inserting a new gasket. It can be coated with a few dabs of tacky grease or gasket sealer/dressing to help hold the gasket in place when the cover is turned over for assembly. The surface at the head where the valve cover will be seated should also be clean and dry before reassembly.
[[file:900_9-3_VC_6.jpg|thumbnail|none|Fig. 6 - Valve Cover Gaskets]]
====Gasket Sealer====
Sometimes a new gasket is not engough to stop the leaks. In that case, small amounts of silicone gasket sealer may have to be used in areas where the cover leaks, like the half-moon seals which close off openings in the block. Otherwise some tacky grease or gasket dressing is sufficient.
[[file:900_9-3_VC_7.jpg|thumbnail|none|Fig. 7 - "Half-moon" seals to be filled with Gasket Sealer]]
====Valve Cover Plug====
If the plug was also leaking, it can be replaced or sealed with Permatex sealer, as shown on the left. For more details on the plug:
[[file:900_9-3_VC_9.jpg|thumbnail|none|Fig. 8 - Valve Cover Plug]]
[[900/9-3 Valve Cover Plug Repair|Valve Cover Plug Repair]]
====Valve Cover====
The valve cover is turned over carefully with the gasket in place and replaced on the engine. Use two bolts to locate the cover in the correct position. Next check the position of the half-moon seals. Finally, tighten valve cover bolts to about 11 lb-ft, in the sequence shown at left.
[[file:900_9-3_VC_8.jpg|thumbnail|none|Fig. 9 - Valve Cover Bolt Tightening Sequence]]
====Remaining Parts====