Valve stem seals replacement

1978 BUICK REGAL
100,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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Hi, I believe the valve stem seals are shot on my 305 due to the fact that on startup and idle it blows light amounts of smoke out the tailpipe and after being driven or revved the smoke goes away for a little bit. I've never done anything on any heads before beside valve cover gaskets, is this a simple task I know there's the rocket arm, push rod, and the spring which in the center has that clip but on how to properly remove all this and reinstall it is alien to me. So pretty much what I'm asking for is a detailed process of the task and if it's something I can do myself. Also if there's any small upgrades I can do while I have these pieces off a list would be great.

Thank you to all who read and to any responses.
Apr 5, 2020 at 3:38 AM
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ASEMASTER6371
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Good morning,

The originals may be the o-ring style but the replacements should be the umbrella style. That is one that wraps around the valve guide so very little oil goes down the stem.

Also, when you have it apart, see if the valve moves side to side. If it does, the guide itself is worn and needs to be replaced.

https://www.youtube.com/watch?v=wz9ghrow9ps

https://www.youtube.com/watch?v=OsGqmOQus6Y

Roy

Apr 5, 2020 at 5:03 AM
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Thank you.

I've also noticed that some of the oil drain passages in the head are clogged and not all of the oil drains back down to the bottom, can this also cause my smoke? I've heard using engine flush stuff can clean these out can that fix it?
Apr 5, 2020 at 5:48 PM
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ASEMASTER6371
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Yes, that could cause it and is common.

Scrape out all the sludge on the head and clean out the holes.

Then, you need to have the oil system pressure flushed. This is not adding a flushing agent to the oil, it is a machine where you drain the oil, put an adapter on where the oil filter mounts and one in where the drain plug goes.. then this machine forces fluid through all the oil passages and cleans all the dirt and debris from the engine back into the machine by recovering it from the hose on the oil drain plug. It cleans the heads, valley and oil pan of all dirt and debris.

Roy
Apr 5, 2020 at 5:52 PM