Engine rebuild- freeze plug question

[fjleiter]

Installed all the freeze plugs in my new block, oil galley plugs were tapped for threaded plugs. Anyone know how far the plugs should be "screwed" in? Do I crank them down tight or leave them sticking out some? I know the typical cup plugs are fairly shallow, the threaded plugs are like 1/4" longer and I don't want to crank them down and have them blocking a passage or something.

 

[1-ton]

I usually torque them in until they are about 1/16 of an inch from flush with the block. You can go flush with the block if they are still not quite tight enough at 1/16" from flush.

When I am building an engine, I run a pipe thread tap throught the oil gallery plugs, and then wire brush them to make sure the oil gallery plug threads are clean. Then I use a non-silicone sealent on the plug threads, and screw them in until the previously mentioned tightness.

 

[4X4HIGH]

The threaded holes are NPT (national pipe thread). This means they are tapered threads and the plugs need to be installed until they are tight. Make sure you use some kind of sealant such as teflon sealer.