cylinder head removal

[bobc]

Hey guys, could use some help.

About a year ago an exhaust manifold stud broke right at the cylinder head. Now it's started to leak, so I attempted to fix it today. I've tried to drill out the stud, but I'm not getting anywhere, so I guess I need to take the cylinder head off and take it to a maching shop. It's only been 35 years since I did this, so I'm a bit rusty.

I bought the chain retainer from Motorsports today, but can't remember which side to put it on. Last time I made my own out of wood!

Do I need to take the rocker arms out first? Instructions say to take the oil gallery off too. Why? Can the cam stay in as well?

Again, it's been awhile so I appreciate the help. Couldn't find a step by step in the archives, and I'd like to get it off tomorrow, so I can take it to the machine shop on Monday.

Thanks.

Bob

[tibZ]

You might want to give the drill another chance first. If both manifolds are off,take a file and smooth out the top of the broken stud so you have a flat surface to start with. Then center punch the center of the stud with a punch. Then drill into the stud with a 5/32 drill.Take your time and let the drill do the work, don't force it or you could break the drill in the stud. Buy or borrow a set of "easy-outs" and use one that goes 1/2 way to 3/4 into the hole. Tap it with a ball peen hammer to seat it. Put a wrench on it and turn counterclockwise.

If you do pull the head you don't need to remove any of the components, but it will be heavy, make sure you set it at top dead center first.

[bobc]

Thanks, but I've given up on getting the stud out. That's why I'm thinking machine shop. I've already broken an "easy out" in it and that's one reason I can't seem to get a drill bit to catch to make a new hole to try again. What a PITA!

Anyone have any advice on taking the head off? It would be appreciated. Way to long to remember how I did it the first time!

Bob

[blue 72]

I recently had my front cover off (let the chain slip without the tool in place) and took a picture or two.

This shows the tool in between the chain, but not pushed down all the way to the lower chain sprocket yet. You want to make sure it is pushed down all the way, or else the tensioner is still likely to come out (like you can see in the photo).

When I had everything reassembled and timed correctly I shoved MSA's little tool all the way down in the middle, between the chains. This kept enough tension on the chain and separated them enough that the tensioner couldn't slip out of its holder again. I made sure to leave it in place until the cam sprocket was bolted on and tightened down this time.

[d240zx2]

BobC, if you have an arc welder available, you can get that broken stud out pretty pronto without damaging the head.

Get some small diameter high-tensile strength electrodes (110,000+ psi tensile), 1/16" diameter. Set your machine to run on the cold side, 35 - 40 amps. Place a steel washer over the broken bolt and begin "dabbing" at the broken bolt with the electrode. Don't worry about chipping the slag. Keep "dabbing" until you've got a bit of a build-up. Let everything cool for a minute or two, then get a nut and weld that to the build-up you've created. Allow to cool until you don't smell burning flesh when you touch it. Take a wrench and back it right out. If done properly, it shouldn't take you more than about 10 minutes. I speak from experience on a Chevy 454 and my own L24. It works.

Good luck.

Frank

[bobc]

Frank,

Wish I had that skill. Unfortunately, welding isn't in my skill set (yet!). I've got the head off, but I think I sort of screwed that up a bit! See my new post.

Bob