Small Holes in Ports: KZ440B

So, I finished cleaning the head and replacing valve guide seals on my 440. I noticed that there is a very small hole visible in all four ports. They are too deep and too small to show up in a photo, so I'm sorry but I don't have one. The holes feed into the tapped and threaded holes for the cam cover bolts and apparently were created during manufacturing.

Does anyone know what those are? Do they pose any kind of vacuum leak issue? Since the FSM calls for thread locking compound on the cam cover bolts, will that effectively seal the holes off or do I need to consider some other kind of sealing compound?

Sounds to me like you're talking about oil holes for the cam journals There might be two holes in the exhaust ports between the guide and the long side of the bowls. Those would be for air added to the exhaust.

I can't think of any holes in the intake ports themselves.

Are these them?
Exhaust is a 400 crossover(ie Smiley face)
Intake is the rocker box bolt on a 440,I have another 440 head without the hole.
No other holes besides valve guides to be found.

Nebr_Rex wrote: Are these them?
Exhaust is a 400 crossover(ie Smiley face)
Intake is the rocker box bolt on a 440,I have another 440 head without the hole.
No other holes besides valve guides to be found.

I can't really tell from these pictures. The holes are really tiny and appear to have been made when tapping the head for rocker box bolts. It looks as if when drilling those holes they just went through far enough to create the pin holes in the ports. It may be just sloppy workmanship, I suppose, or it could have had something to do with judging the depth of the bolt holes.

Had a "proper" mechanic tell me that they posed a potential vacuum leak problem and that I should use some kind of sealant when reinstalling the rocker box bolts. The FSM calls for thread locking compound on those bolts (and doesn't call for anything else), so my guess is that this will solve the issue, if there even is an issue. The fact that you have found such holes on your 440 tells me that it is likely no big deal.

Thanks.