I have an T IV engine that has sat in my garage fully assembled for seven years. I would like to know if I should replace all galley plugs prior to installing and using it. The cautious part of me says yes, the other part says I shouldn't have to. What do you guys say?

I remember reading, sometime in the recent past, an article on the changing composition of new lubricating oils and the older 911/914 oil cooled engines requiring certain percentages of zinc and phosphate additives that are no longer part of the mix.
I remember the article listing oils that contain at least 12%. Does anyone remember in what publication that article appeared?

Unless you're taking the engine apart, leave the gallery plugs in. You can epoxy over them, which can help keep them in. Clean the area thoroughly first, though.

Oils:
http://www.lnengineering.com/oil.html

--DD

Think about this for a second.
IF you drill and tap for "screw in" galley plugs.

What happens to the aluminum shrapnel you create during this drilling and tapping process?

At best. Even of you use a bunch of grease to trap MOST of the shrapnel.And then attempt to get the grease removed with carb cleaner. Which is being sprayed INTO the galleys. Not out of them from the inside.
You will still have a bit that gets into the oil galleys. Then the bearings. Then the oil cooler. Then the oil filter.

IMakes ya wonder if the aluminum in the block is softer than the crank and rod bearings.. I think not.

Me thinks that may not be the best route to go at this juncture. Especially on a new engine.

Conversely. if you take the entire engine apart and start with a bare block....

That would be my first choice.

As an alternative. Pull the sheet metal so you can access the plugs by the oil cooler.
Then simply get a punch or chisel and dimple the aluminum around the plugs.
At least if a plug starts to let go. it won't fall out and take your engiine with it. (Hopefully.

In this process. You must make sure NOT to touch the plugs with the punch / chisel. As this may well dislodge it and make it leak or flip a little sideways. (Thats bad)

Or you can simply install new plugs with gaskacinch and then dimple the case if you choose.

The above is just my opinion.
NOTE: I DON'T trust the factory oil galley plugs. Period. The block and the plugs have been heat soaked a bunch of times.
The elasticity and the STICTION (for sake of a better word) of the metals will be suspect at this point.

Now.. is there any way I can confuse this thread a bit more?

Cheers and great luck on your endeavor.

Clayton