A caveat to what Doug has said is that the main stud corrosion will occur where the studs sit in the coolant jacket, not where they sit in the head, and this is below the block deck, so not immediately visible once you have the head off, so I would reiterate the need to at least inspect them via the core plug holes. My 1980 studs had corrosion, but were not so far gone as to prevent me removing them using a heavy duty stud extractor. You just have to assess them and make a judgement.

 

Hi Doug,
I am trying to be patient with the process. I am a little worried I might punch the jack head through the Aluminium Cast. This is my third day with pressure on the head with little or no movement. I worry that someone use a gasket cement on this head. I get the yeps pressing on the jacks thinking I am going to crack the head. Then we both know the next step in that process.
Thanks,
Oh, what about the tube sawtooth drills to cut the treads. Do you have a suggestion as to where to get these?

 

Fraser,
Thanks for the advice. I am thinking that is what I will be doing as soon as I make some progress on getting this head to move.

 

This is really directed to Doug and Fraser, but should not the cam and chains have been removed before jacking? See photo 1 earlier in thread.

As you will gather I have not pulled one of these to bits before.

 

Hi Richard,
I have disconnected the camshaft sprocket and chain from the cams. I was hoping to just leave the cams in place and take it to the shop for the valve job. I would rather they take it down to not get the valves mixed up. That I understand the cam shaft is simply bolted to the head. No connection to the block.
Please someone correct me if I am wrong.

 

Ok to leave the cams in the head. Oh.....Do NOT set the head down flat. You'll bend the valves...which just *barely* extend beyond the bottom of the head.

Cheers
DD

 

Thanks for clearing that up Ken. You had me worried when I saw the timing chain.

 

In view of the ease with which I managed to remove my 4.2 head all those years ago, (about 20 !!) I wondered what could be stopping it lifting. Hell, guys, this job should be easy, it is not a V12 !!!

Clearly time moves on, and when I took mine off the car it was about 10 years old, whereas they are all a lot older now and corrosion enforces its vice-like grip, (or so it seems with thirdfloor's engine). Most of the long studs are a fairly loose fit in the head passages, only the stud that has the dowel fitting will be tight as it is meant to be. Identify this stud and try to remove it, it should be short not long, then you can wallop the head a bit from the side to see if it will release.

Also assume you are going to replace all the head studs and remove those that will come out and leave the rest; forget trying not to damage the threads !!

Other thing to mention is that having undone the bolts clamping the cam chains to the cans, the cam chain should be relaxed on its tensioner, the sprockets then should be pulled off the cams and loosely mounted on the alloy extensions designed to hold them so there is no connection at all between cam sprockets and cams.

Sorry to say these things, but I am clutching at straws here to explain what might be stopping the head removal.

Other thing to try is rebolt on the exhaust and inlet manifolds and try a sideways approach to lift, first one side then the other, rather than fore and aft. There is more leverage there. First off a couple of hammer handles in inlet and exhaust ports and a couple of your friends to alternate the effort side to side.

Believe me, you have my sympathy. I feel for you !!

 

I've heard from guys who attached an engine hoist to the cylinder head and lifted the front of the car clear off the ground and still the head remained in place for 2-3 days....with daylight showing under the front tires... before giving up its grip on the studs.

They all come off eventually, though :-)

Cheers
DD

 

Thanks guys for the advise. I am trying to be patient in the process and not break to many things. My biggest fear is that I am going to crack the head with all the pressure from the jacks.
I will try some of the things you have all mentioned over the weekend. Maybe it is just one bad bolt holding things up. If I start breaking head bolts not looking forward to drilling and tapping a foot away from the hole.
I think it is good and stuck at this point.

 

It might be worth slowly heating it all up with a couple of blowlamps, but only to around 100c, not any hotter, plus penetrating oil down the studs. I agree abut the jacks; better to use hoist technique. As Doug says, it worked for him !! Identify the dowel stud and get it out if you can; it stops any head-block movement, as it is meant to do, but doesn't help with removal.

 

Ok, so here is the latest update. I think I am going to pull the entire engine. Take it to the machine shop. They can heat the engine in a vat to loosen the head. At the same time have them replace the head bolts. If they snap them off they can drill and replace while it is in the shop. Think I am going to be paying $700 to $900 per thier quote. Not bad.
They will do the replaining of the head and the valve job. put the new head gasket in place and toruqe the head nut back down.
Don't seem like I have any other choices due to the corrosion issues.