Question on head oil galley

[Sangerboy]

Are the threaded plugs on the end of the heads closing an oil galley? I just reinstalled a 7.3 that I rebuilt in my daughters '93 F350. It is an NA motor but had an ATS turbo system with intercooler installed when we bought it. I am sorting out minor issues one by one but the first time I brought it up to temperature I noticed an oil drip from the bottom back of the driver's side head. Heads were rebuilt by a reputable shop. If those threaded plugs cap an oil galley that is where I am going to look first and am most suspicious of. Of course it is on that spot that is so close to the firewall I cannot get a good look at it. Thanks for any help you can give. Greg

 

[FrozenMerc]

Pull one of the plugs that are at the front of the cylinder heads and see what runs out. The heads are ambidextrous, so in theory the galley is the same on the front of the opposite side head.

 

[IDIBRONCO]

From my small experience, they usually seem to act like they've been welded in. I haven't tried to remove very many, maybe 2 or 3? Those wouldn't act like they wanted to budge though.
I also tend to doubt that they are oil gallies. There's no oil pressure in the heads. The oil comes up through the push rods and then drain back out by running into drain holes in the heads. My first guess would be that they were casting holes to help gasses escape during the process. They could then be drilled, tapped, and plugged. 7.3 PSDs, on the other hand, do have pressurized oil inside the heads. I know that they have plugs that can leak fuel, but I don't remember if they have plugs that can leak oil.

 

[ROCK HARVEY]

At least one of them is a blind hole, because the heads are the same for both left and right and the driver’s side head has a ground wire that’s bolted to the head using one of those holes.