Intake/Exhaust manifold

[JohnnyP]

So I'm new to this world of restoration.. This is my first car.. I'm in the process of removing the intake manifold on my '76 280z and I'm a little stuck. I've removed the intake manifold bolts holding it to the head, I don't know where to go from here. I have removed everything that looks like it would be in the way but the thing won't budge..

I guess my question is how do I pull the intake manifold?

My Haynes manual is in the mail.. Any and all help would be greatly appreciated.

[280~Master]

Johnny there are a few bolts and nuts that sit out of site. if you look in my gallery there is a picture of a head with the nut and bolt markings on it.

My Gallery

[JohnnyO]

I have a 240Z so it may be different but I removed all bolts from intake and exhaust. After that I took a block of 2x4 and put it against the exhaust manifold and gave it a good shot with a 3 pound sledge. It was just enough to loosen the gasket enough to "peel" it off the rest of the way.

Hope that helps.

John

[Zs-ondabrain]

The bolts on top are not the only ones. There are nuts all across the bottom of the intake that are "Shared" nuts. They hold the bottm of the intake and the top of the exhaust. You need to loosen all of them before the weight of the intake will pull the intake away from the head. DON'T USE A HAMMER!!!

In the picture below (not a great one for the discussion) you'll see three top bolts, 3 middle nuts on studs and 3 bottom nuts on studs. The middle ones are the "Shared" nuts that need to be loosend, all the way across.

Dave

[JohnnyP]

In order to reach those middle nuts do I have to remove the heat shield underneath the intake? And where are those bolts at? I have felt around underneath and have located a few but may have missed - or not be knowledgable - to the others

Thanks for the the help this far, everyone has been a great help!

-Johnny

[Zs-ondabrain]

Some are in blind spots, you just have to feel around.You need to reach under the exhaust manifold to get to them. The heat sheild is typically mounted to the intake.

I can pesonally do it with my eyes closed but like I said, you gotta just feel around. Hell, just loosen every nut you find under there. Just remember to tighten then all back up when you're done. haha.

Dave

[Zs-ondabrain]

Use this picture (taken from the gallery) to familiarize yourself with the bolt patterns and locations. Thanks Dkd021, great picture.

Edited October 6, 2009 by Zs-ondabrain

[JohnnyP]

So I've managed to locate all the hidden bolts and nuts but when I try and fit a socket to them it slips. So I downsize to the next lowest socket and it just slips everytime, until I get to too small of a socket and it doesn't fit. My question is what's wrong here and what's the best way to loosen this nuts? Should I be concerned?

Thanks again everyone, your help has been greatly appreciated!

-Johnny

[tomb]

You must use metric sockets. 10, 12, 14 are the most common.

[JohnnyP]

So I have two bolts remaining under the intake and I have them fit to a 12mm socket. I was having trouble gripping them with the socket so i managed to get a hold on them with a wrench (same size). But whenever I think I'm getting a good hold on the nut, I realize that the wrench is just turning around the nut.. Is it possible that those two nuts are rounded off and unable to be gripped? I threw some heat at them, tried some liquid wrench as well.. Any suggestions?

Everyone has been a lot of help, those pictures helped immensely! Thanks everyone.

-Johnny

[beandip]

Sounds like the nuts are rounded as you said. Liquid wrench is a poor substitute for Kroil or PB Blaster.

Do you have a Drummel or have access to one? You may find that you will have to split the nuts . Before you do this though, look into your socket and count if it is a 12 or 6 point socket. If it is a 12, this may be part of your problem if the nut is rounded off some. A 6 point will capture the flats on the nut better and is less likely to slip.

Gary

d

[JohnnyP]

I'm using a 6 point socket. I did try a 12 point at one time but that wasn't catching at all. The 6 point catches, and when i turn it its pretty tough, could it just be so tight that instead of loosening the nut, the socket (or wrench) just slips?

I do not have a drummel but might be able to get my hands on one.

Thanks again

-Johnny