Is your head stuck on your block and can’t get it to come off?
This article will give you some ideas on how to “unstick” it. There are reasons for it to stick to the block and sometimes not always a easy solution to removing the cylinder head. There are no places to lift from, and do not use METAL objects to lift the head from below. You will damage the block, mating surface or mar the head so bad it might need to be milled or welded and then milled.
The most obvious thing that would hold the two parts together (block and cylinder head) is the head gasket. We put it together to hold so it doesn’t leak gases or fluids. There are head gaskets and there are head gaskets. This meaning that some hold better than others. Victor is the choice of mine as they have been around forever it seems like and if the head is done like my previous article on head gaskets suggests, they won’t leak. The tool to use is the Alfa tool for breaking the seal. It mounts in the spark plug hole with the adaptor, then a plate goes on top of the adaptor that has 4 indentations for the studs. A large washer is put on next and a 19mm nut. You tighten the nut, while it is pulling up on the head via the adaptor that is in the spark plug hole. It will break the seal and raise the head about an inch. You do this on spark plug hole #1 and on #4. Now the head should be loose and lift right off. Theoretically…
Ok, I installed the tool but the head won’t move. What is next? You sure you removed all the bolts and nuts that hold the head on? Oh…Wait! There are two (2) bolts that mount “under the block” that screw into the bottom of the cylinder head. There is one that is easily seen on the exhaust side which most people get. But just above the distributor on the “other side” is a shorter bolt. Both are grade 8.8 and different lengths. You cannot put the longer bolt in to the distributor side hole, as it will lock the tensioner so it won’t move. Now you can’t tighten the chain!
Let me interject this here as I just thought of it…get yourself one of those magnetic trays that holds nuts and bolts. It mounts anywhere there is a magnetic surface, and you can just toss your nuts and bolts into to the tray. They stick and are easy to retrieve.
Now…you have all the nuts off the cylinder head, exhaust is loose, the carb support or injection pipes and retainer bracket is loose, the two bolts I just mentioned are out, chain is dropped down into the galley with safety wire attached for retrieval, hoses are loose or removed. Now you should be ready to remove the head. Install the Alfa Tool and break the head free from the block. Oh…it only moved a fraction of an inch. Now what?
After verifying you have removed all that can hold the head you are now in a place you really don’t want to be if the head only moves a fraction of an inch or so. For the sake of conversation, what if the head is loose and you can lift it but it jams half way up? Most likely you haven’t lifted “straight up” and have the head jammed. If you stand back you will see one end is higher than the other. So you push on it and it won’t move. You better have a good copper mallet, and a 2×4 block of wood about 12 inches long. You put the block of wood on the top of the cylinder head that is higher, and give it a good rap with the mallet. The head should drop back to the block. Now lift it correctly and it will come off. Have some one standing next to the fender with a thick cover on it, so it won’t drip oil, antifreeze or gasoline on the paint. Have the head sitting on the studs and hand the head to your support person to stand on end on a rag to catch the residual oil that will run out.
Ok, that all sounds great, but if we consider the other scenario, we are dealing with a “horse of a different color.” We have the worst situation imaginable. The studs are corroded so bad with either rust from using plain water for coolant, or gunk that the spare clearance around the stud and cylinder head is now virtually gone. There is only a few thousandths of an inch or less than a millimeter or two between the stud and the cylinderhead. The material on the stud is the worst, as it won’t let go of the cylinder head.
This is going to take a few days and it can’t be rushed. I have had several heads that I have had stick on me and nothing is easy as it would seem. Get a couple of cans of carburetor cleaner with the plastic tube inserted into the atomizer. You are going to spray liberally around the studs the contents of one of the cans. This will let the carburetor cleaner soak down in to the holes and soften the gunk. If Bars Stop Leak was used at some point, this could be the culprit. If it is rusty corrosion, you might want to consider removing the liners to look at their sealing surface for pits (Yeah, I know…you don’t want to do a tear down). An old Fram ad said, “You can pay me now or you can pay me later. ” Trust me, if it is that corroded the liners are going to leak.
So you go out the next day and try lifting the head. If you are the lucky one (Allison Krauss song) you can get some movement in the head up and down on the studs. Apply some PBlaster Penetrate down the stud holes to make it more slick on the studs so you can lift the head off. You might have to move it up and down an inch at a time until you can work it free and off.
Oh…that didn’t work either. Ok, more carb cleaner and PBlaster down the stud holes. Don’t worry it won’t harm anything as it will just dribble down into the water jacket and it won’t etch the aluminum. You might try some Kano Kroil if you can find it or order it. The other option is to get some transmission fluid and acetone mixed 50-50. This is THE BEST pentrating fluid. Read my article on “The Best Pentrating Oil.” Inject that down the stud holes and let it sit for 24 hours. You might apply some more after a few hours to make sure it is getting down in and around the studs.
The part that I hate is next as it is pure “grunt work” getting the cylinder head off. You DON”T want to use anything that will mar the surface of the cylinder block or head to pry it loose. Use the Alfa tool for breaking the head loose and add the acorn nuts just enough to be on the threads. This will add extra height to pull the cylinder head up more. Insert any thing wood to hold that head up. Preferably two pieces across the #4 and #1 cylinder. Now apply more liquid to the holes. You are now in a different spot so more fluid is required. Now you will need another piece of wood to put against the cylinder head to lever it up. If you have the studs free to move, the head should go up and down. Keep pulling on the head and pushing with wood to lift it at the same time. This might be a two man job. If you can put a 2×4 on the liner vertically on its side you are almost off the studs. Just keep working it up and down and it will eventually come loose. The last inch is the hardest as the threads on the studs are now loaded up trash from the cylinder head and will want to grab the head. “Patience will win out here” if you are in the proper mindset. You might have to stand over the engine and lift the head up and down until you can get it off. Leaning over the fender is the hardest thing on your back. Like I said it is “grunt” work as you will grunt getting it off.
Now that you finally got the head loose and off the engine, peel off the gasket. Some of it will be left behind, but not much. Use some carburetor cleaner or acetone to soften the gasket enough to remove it. Read my article on “Don’t blow a head gasket” about how to clean up the surfaces and how to insure you get a good seal.
You could send the head out for a check to see if it is straight and needs a clean up mill. If not, clean it perfectly smooth and reinstall.
As to the studs, lets get serious here for a moment. You realize what just happened to your back and mind set getting that cylinder head off the block? It all went down hill. Someone didn’t take care of the engine like they should have and you had to pay the price. Get some 400 wet/dry sand paper and sand those studs clean of any and all rust or gunk. Usually I put pipe cleaners in the oil passages and rags in the chain galley. I take my drill and a wire wheel to the studs to get a majority of the trash off of them. You might find they are pitted which is typical. You might want to remove the side drain for the water galley and check the bottom of the liner area to see how corroded it is. Then run a thread chaser die (12×1.5 mm) over the studs threads, and a corresponding tap down the threads on the acorn nuts that go on the studs to clean everything like new again. You will be surprised how binding the dirty threads are. Next you want to get a wire brush to go down the stud holes in the cylinder head to make them like new again. You can tell they are good by shining a light down from the top or bottom to check for cleanliness. It should be shiny in the holes.
Read the articles on installing a head gasket and o rings I wrote to get those tips to insure you get a good seal.
Thank you for reading this far down.
I sincerely hopes this works for you. If you have any comments or suggestions that work for you or I missed. Drop me a line at 65veloce at gmail. com I will consider your thoughts and add them to the article for an updated version. I don’t claim to know everything as there are many solutions to problems and I might have only seen one. Have any suggestions for articles? Drop me a note and I will see what I can write up.