Head Bolt Removal 85 XJ6
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#3
Thanks
Doug,
Thanks for the reply. I will look for one tomorrow. I am using the penetraing oil hoping it will help. Looks like most that have tried this usually break them. If so I guess I will be doing some drilling. ha.
Love this site and working on my car. Can't wait to finish the work.
Thanks for the reply. I will look for one tomorrow. I am using the penetraing oil hoping it will help. Looks like most that have tried this usually break them. If so I guess I will be doing some drilling. ha.
Love this site and working on my car. Can't wait to finish the work.
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#6
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Look how the head fits on the block: it is wider the the top of the block and the overhanging edge/ledge is perfect for pushing upward with a bottle jack. The bottom of the jack is placed at various casting abutments on the sides of the block near the bottom....where ever and however you can manage. I can't remember each exact spot but you'll see 'em.
It usually takes a day or two of pushing with the jack in various locations on both sides. Apply pressure, walk away. A few hours later apply some more. Etc etc. Eventually the head will break free by 1/8" or so. Then just keep going from side-to-side to lift it up evenly.
Or remove the studs and you'll have it off in minutes. But....a stud broken off deep inside the block (they go all the way down) will really ruin your day.
I've done it both ways depending on the circumstances at hand.
Oh....remove the intake manifold with the head still on the block. A bottle jack is useful for that task as well. Just don't break the casting ! Apply pressure at the beefy parts of the manifold.
Cheers
DD
It usually takes a day or two of pushing with the jack in various locations on both sides. Apply pressure, walk away. A few hours later apply some more. Etc etc. Eventually the head will break free by 1/8" or so. Then just keep going from side-to-side to lift it up evenly.
Or remove the studs and you'll have it off in minutes. But....a stud broken off deep inside the block (they go all the way down) will really ruin your day.
I've done it both ways depending on the circumstances at hand.
Oh....remove the intake manifold with the head still on the block. A bottle jack is useful for that task as well. Just don't break the casting ! Apply pressure at the beefy parts of the manifold.
Cheers
DD
#7
Having taken of the head off an XJ6 three times, my advice is to remove the head and leave the head studs in place for now; they are about 12" long and pass right through the water jacket in the block, and get very corroded, so much so, in fact, that attempts to remove them can result in the stud snapping towards the bottom making replacement a real pain, and can be almost impossible. I have not had any problems removing an XK head apart from its weight, so you probably need a friend or two, plus some means of hauling it up gradually off the studs.
Once the head is off, you should remove the core plugs next to the bottom of each stud and inspect for corrosion. Those studs that are so corroded they look about to snap off should be carefully extracted using the stud extraction wrench whilst looking to see if the stud is coming out using the core plug hole to see. Don't rely on the stud apparently rotating at its top end, it could be about to shear off at the bottom. I am not sure if all 14 studs are long, the two at the rear of the block may be short, I can't remember from my own rebuild it was too long ago. Before removing and replacing studs flush out the block coolant jacket so no crud can enter the tapped holes for the studs
Do not ignore corroded head studs, they must be replaced to maintain the integrity of the engine. Of course if previous owners have always maintained the antifreeze correctly, the corrosion should be less, but there is usually always some.
Once the head is off, you should remove the core plugs next to the bottom of each stud and inspect for corrosion. Those studs that are so corroded they look about to snap off should be carefully extracted using the stud extraction wrench whilst looking to see if the stud is coming out using the core plug hole to see. Don't rely on the stud apparently rotating at its top end, it could be about to shear off at the bottom. I am not sure if all 14 studs are long, the two at the rear of the block may be short, I can't remember from my own rebuild it was too long ago. Before removing and replacing studs flush out the block coolant jacket so no crud can enter the tapped holes for the studs
Do not ignore corroded head studs, they must be replaced to maintain the integrity of the engine. Of course if previous owners have always maintained the antifreeze correctly, the corrosion should be less, but there is usually always some.
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#8
Thanks gentleman. I used the bottle jack for the intake removal. Worked like a charm. Popped right off. The jacks are under the head now. Just giving it time. Slowing moving the locations and making sure the jack is under pressure. Been at it all day. No movement of the head yet. Got the stud remover but thought I would wait to use it until I lift the head off.
Question: Would applying heat from a tourch help speed up the process? Or to risky?
Thanks,
Question: Would applying heat from a tourch help speed up the process? Or to risky?
Thanks,
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#11
I hope I don't sound patronising, but I assume you have also undone the four nuts on the short 5/16" studs on the underside of the head which secure it at the front by the cam chain box. They poke downwards through an extension of the block casting and are only there to seal the head gasket joint by the cam chain box so oil doesn't leak out.
If you have and the head is not moving, it sounds like the head has corroded where the studs pass through it, and has "welded" stud and head together. A bit of penetrating oil might not come amiss, faiing that, it used to be possible to buy headstud easers which were thin wall tubes with a sawtooth end that could be inserted and the turned to free off the studs. The head does not normally stick to the gasket at all, at least not in my experience. This of course assumes that some Charlie All thumbs has not glued it down using gasket goo.
If you have and the head is not moving, it sounds like the head has corroded where the studs pass through it, and has "welded" stud and head together. A bit of penetrating oil might not come amiss, faiing that, it used to be possible to buy headstud easers which were thin wall tubes with a sawtooth end that could be inserted and the turned to free off the studs. The head does not normally stick to the gasket at all, at least not in my experience. This of course assumes that some Charlie All thumbs has not glued it down using gasket goo.
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Sawtooth tubes? Fascinating. Wish I had know about them in the past. Sounds like a perfect solution. Who sells them? Do you have a pic?
Good point about the nuts at the front of the head. I meant to mention that but forgotted :-)
Hopefully the cylinder head will never have to come off again in this or any other owner's lifetime. However, anticipating the future, I turn a wet stud head into a dry stud head by sealing off the studs at the top of the block. Having the studs swimming in coolant (and eventually caked with corrosion) serves no purpose that I can think of.
Cheers
DD
Good point about the nuts at the front of the head. I meant to mention that but forgotted :-)
Hopefully the cylinder head will never have to come off again in this or any other owner's lifetime. However, anticipating the future, I turn a wet stud head into a dry stud head by sealing off the studs at the top of the block. Having the studs swimming in coolant (and eventually caked with corrosion) serves no purpose that I can think of.
Cheers
DD
#14
I had a tool made up from an old stud and a tap to clear out the tapped holes for the studs at the bottom of the water jacket. On my replacement block I took all core plugs out including the small ones and thoroughly flushed out the jacket, plus using a bit of wire to move the crud. It gets really bad at the back of the block farthest from the water pump.
Other thing to check is the timing chain cover where there is a passage through to the block from the water pump passage. Corrosion of the aluminium can be such as to get very close to coolant leaking into the camchain chest. If you have to fit another one, you have to bolt it up to the block then lightly skim both to eliminate any step on the deck between block and cam chest cover.
Other thing to check is the timing chain cover where there is a passage through to the block from the water pump passage. Corrosion of the aluminium can be such as to get very close to coolant leaking into the camchain chest. If you have to fit another one, you have to bolt it up to the block then lightly skim both to eliminate any step on the deck between block and cam chest cover.
#15
Yes, I removed the underbolts at the front. So I am clear on all the bolts and nuts being removed. We had the left overs from a hurricane hit Austin for the last coulple of days so haven't been able to work on the car. I did check the jacks this morning and it is lifting. Yeah. Yes, I am using a penitrating oil on the bolts and cracks. I am sure the previous owner did not do even the simple maintenance to this car. Ought to be flogged. No excuse. I am very nervous about extracting the headbolts once the head is off. But I am sure the bolts are a mess. I will check the plug holes to view the shaft of the bolt but thinking if it will suffice for this head job I will just leave it alone and let someone else do it next time. I am thinking if they snap and I am into drilling and extracting from a long distance....not going to be easy.
So the sawtooth hollow drill....should I consider using before extracting the bolts? Where do you purchase? Are they plenty long enough to get through the block?
Thanks again for all of your advise. Great forum.
So the sawtooth hollow drill....should I consider using before extracting the bolts? Where do you purchase? Are they plenty long enough to get through the block?
Thanks again for all of your advise. Great forum.
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#20
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I am very nervous about extracting the headbolts once the head is off. But I am sure the bolts are a mess. I will check the plug holes to view the shaft of the bolt but thinking if it will suffice for this head job I will just leave it alone and let someone else do it next time. I am thinking if they snap and I am into drilling and extracting from a long distance....not going to be easy.
So the sawtooth hollow drill....should I consider using before extracting the bolts?.
So the sawtooth hollow drill....should I consider using before extracting the bolts?.
Once the head is off there's no need to extract the studs unless you're sure there's something wrong with them (like they've corroded down to a mere wisp if their former selves) or you're itching for a problem :-)
Cheers
DD