Center Exhaust Manifold stud on a 6 bolt

I don't want to go into why there is an M12x1.75 bolt going through this hole, but I want to know if the bolt needs to be flush with the head on the inside of the valve cover or protruding into it is fine.

As a reminder, this is the center stud hole on a 6 bolt where the oil drains from. The bolt is now protruding into the valve cover and is almost bottomed out.

I have much to learn when it comes to cylinder heads and engines, but figure that this bolt has nothing to do at all with the combustion chamber or flow etc.

I don't want to lose power or hurt anything. The bolt is secure, and has a lock washer on it. I am not too worried about it backing out. I am just wondering if I am hurting anything by it sticking out in there.

Thanks

 

[rdomeck]

Picture. This sounds a little confusing to me......

 

Camera sucks, so that's why I didn't take a pic. I'll try later. Just picture this. Instead of there being an M8 stud in the center hole of the 9 exhaust stud holes on a 6 bolt, there is a bolt. If you were to pull the valve cover, the bolt would be protruding past the threads into the head and into the valve cover.

 

[iceman69510]

If you are referring to the center bottom stud, it normally goes through to the oil return passage. That is why you need to seal it, When you say "12 mm", do you mean the head size, or the actual bolt thread size?

Don't picture how this gets anywhere close to the valve cover.

 

I mean the thread size is 12mm and the pitch is 1.75. The head size is 19mm. I know that this is VERY large, but I did what I had to do.

I know that the bolt goes to the oil passage, and I sealed it with "the right stuff". If you lift the valve cover you can look down and see the threads is what I meant.

I am wondering if it is ok to see the threads (about an inch of the threads) or if that is a big no no for some reason e.g. hurting flow, drainage, or something that I hadn't thought of.

Thanks

 

[ghostinthevr4]

If you sealed it with right stuff you'll be good. It obviously is going to block the flow of the return of the oil just a lil bit. I really don't think you have anything to worry about. The oil flows back at all four corners of the head if I remember correctly, and theres another drain opposite of the one your talking about.

Run it.

 

[mitsuturbo]

I wholeheartedly second what he said ^

 

Quoting ghostinthevr4:
If you sealed it with right stuff you'll be good. It obviously is going to block the flow of the return of the oil just a lil bit. I really don't think you have anything to worry about. The oil flows back at all four corners of the head if I remember correctly, and theres another drain opposite of the one your talking about.

Run it.



So the stock stud doesn't protrude? If it doesn't, I might as well back the bolt out cut it then retap it if that is the case.

Please let me know and thanks for your help.

 

[rdomeck]

I would have to look at the spare head I have, but the stock stud may not protrude. If it doesn't you may have a chunk of aluminum riding around in your head or oil pan......Something to look for!

 

There is no stud in there...I was able to get the stud out.

Got some pics but they are too large to post here.

Thanks for your help.

 

[ghostinthevr4]

Heres a picture hopefully you can zoom in and get a gander of how it should look like with the regular M8 X 1.25 stud in place. I dont know how you got a M12 X 1.75 in there but I gues anything is possible. The oil is still gonna get back to the pan even if your stud is bottomed out.

Run it.

 

Thanks very much for the pic. Yeah the M12 stud was a tight fit but it worked lol.

 

[ghostinthevr4]

No problem, have fun with her.