What goes in the threaded hole in back of block.
- Thread starter TheUser
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Mike86Stang
Advanced Member
Should be a oil galley plug in it if I'm thinking of the same on you are.... if nothing was in it you'd be loosing oil as fast a you could dump it
cardudeusa
Founding Member
There are three plugs at the back of mine one goes to the brake booster the other two were hooked up to vac lines. Just today I took mine out. I hear you can thread spark plugs in the holes 5/8 I think or buy real plugs to fill the holes. One had a little brass rod type thing inside the other one was a little different and was green on part of it. Someone must have removed that on your car and not plugged the hole.......if I am talking about the same things.
cardudeusa
Founding Member
85GT: There's no way we're thinking of the same thing...this is not even close to 5/8. There's only two holes that I see..one is the big one (prob. penny-sized) that is probably only as deep as a nickle or something, you can see the bottom of it and it goes on the inside of the lower intake...then there's the "hole" that's threaded...this is prob. as big as a pencil or something...maybe a picture is necessary. I wasn't losing oil "really fast," but I believe oil was coming out of it. I'll see if I can get a picture in a minute
cardudeusa
Founding Member
Picture would be great. Where is this hole located? Inside or outside of the where the rear intake seal goes? Is it on the back of the block or on back the head? Does it face towards the firewall, or does it face the hood (when closed)? Need more info.
cardudeusa
Founding Member
HUMMMM... I don't remember if mine was plugged or not. I just had the heads off a week ago and can't even remember. I don't see why there would be oil back there, its past the lower intake seal. If you pull the dizzy and prime the oil pump that would tell you where the oil is coming from. You would need a drill and the correct tool to prime the pump.
the weird thing is that i think it only comes out when I go WOT. I'm not sure, but I dried it off behind there and started the car the other day and watched it and it only started coming out when I revved it high. I guess priming the pump might be an option. I'm believe that is where the oil is coming from, so now I need to fix it. I don't want to just put a bolt in it if there's supposed to be something there... 
65ShelbyClone
Founding Member
You know whats wierd? I just looked at some old pictures of my current engine before I put it together and the new block doesnt even have that hole... I have an old late '70s bare block sitting out in the yard I'll check for you tomorrow.
if i had to guess, i would say the oil is comming from your lower intake. or posibly your valve covers. check your lower intake real good back there with a trouble light, mine did the same thing i blew that gasket right out of there at wide open throttle.
Should I plug that hole or is it cool? Lower intake off now - hopefully go back today if weather permits. I haven't decided if i'm gonna use the cork or just a nice bead of silicon - I got the Ultra Copper kind that's good to 700* and supposed to be all around better, so it better not leak this time!
I didn't think to look on my stock 90 LX 5.0 until today...it has the same hole and it's not plugged either. Smog does not go into that hole, at least not on my stock, never been tampered with, 90. I was gonna put a bolt in it, but it appears to be a metric M12 1.75 size, the auto parts stores don't have one and I don't feel like searching. 
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