[size=14px]Oil Pump Drive Seal Fix[/size]
by: Shaun Ewing
You Will Need:
O-Ring, GM Part Number: 10477565
Carb Cleaner (for cleaning the throttle body)
Various sockets and extensions
Completely remove the airbox by unbolting it and removing the intake hose, intake temperature sensor (on the airbox) and PCV tube. This will help give you more room to work.
Disconnect the vacuum lines that are on top of the throttle body (these are all grouped together. Now, remove the two coolant lines running into the TB (These are a major pain in the ass to get off. I ended up cutting mine, and bypassing the TB alltogether). Remove the connections for the Idle Air Control (IAC) and Throttle Position Sensor (TPS). Now, you have two choices. You can leave the throttle cables attached, and try to move the TB out of the way, or you can disconnect those cables and remove the TB completely. I took mine out all the way because it made it easier to clean.
Release fuel system pressure by using this valve. Unscrew the protective cover, and using a rag to catch the fuel, press it down until there is no more pressure left in the system. Be careful, the fuel in this line is under a moderately high pressure, and can come up and spray into your eye. Not fun. Disconnect the two fuel lines that are connected to the fuel rail. Move these out of the way.
Remove the bolt from the C-clamp holding the drive assembly down. Remove the C-clamp. To remove the oil pump drive assembly, you have two options. You can use a sharp chisel and wiggle it under the lip (what I did) or try your luck at using pliers. Whatever you find easier. Remove the old O-ring. (It will be old and brittle and will probably fall into pieces)
Coat the O-ring in motor oil and slide it on into the drive shaft. It fits directly into the grove that the old one came out of. The new GM o-ring is made of silicone and will stretch without breaking (but put it on FROM THE BOTTOM, not the top, It doesn't stretch that much)
Push the oil pump drive assembly back into the hole. It probably won't go all the way in on the first try. Try and try again. Pick it up and rotate it until it goes down far enough to replace the c-clamp (It won't go down ALL the way because of the new o-ring. The c-clamp pushes it the rest of the way down) Reattach the fuel line. Replace the TB and all associated cables, vacuum lines, and wiring. Reattach the airbox and all hoses.
Enjoy your new non-leaking W!