Have you tried dropping it back down and lifting it back up a few times? One would think you could rub off the deposits inside the stud holes.
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Youâre right I noticed that and have been trying to fix it.
I have not tried that yet but it appears that it has gotten stuck how it is because I have released all tension from the tool and the head doesnt want to come back down. iâll try and âgentlyâ hammer it down with a plastic mallet.
You might need to use a BFH and a block of wood.
Yup, I have been trying to get it to move either up or down. I can get it to âwiggleâ on the studs but no up or down movement. I guess I need a metal hammer and some wood. What places are the safest to hit hard?
Canât really advise on that as I havenât worked on a V12 but at a guess along the cam cover seating area would be the area I would aim at.
The cam cover doesnât sit on the head. It sits on the tappet block, and the tappet block sits on the head.
My reason to state that I havenât worked on a V12, so use the block on the tappet block seat of the head.
Ok, big progress! My father and I managed to get the head off without damaging it. We shaved down the end of the bolts so they would go into the holes (some were just a little bit off) and the front outside corner was stuck as could be so we made some aluminum wedges and slowly drew the head up. took a couple of hours but it came off in one piece! It also looks like the bores are in good shape, I quickly cleaned some carbon buildup on one and there is no lip at the top indicating wear, and you can even faintly see the cross-hatching all the way down the bore. I am still going to check all the bores for roundness with my Mitutoyo Dial bore gauge that I snagged off eBay for a good price a while ago though!
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Ok, I have had great success in taking the rest of the engine apart, I was able to get the other head off by just using the head puller I made and managed to not damage any of the studs and they all appear to be in reusable shape. I had a couple questions though, I might be getting this confused with XK but am I able to reuse the Conrod studs and nuts? and can I reuse the main cap studs and nuts? Also I have heard that you should clean out the crankshaft counter weights or some sludge trap, is there a guide to this? or am I just imagining things? even though the engine had perfect oil pressure (70psi cranking) I have inspected the main bearings and conrod bearings, and they have seen better days. I still need to inspect all of them but It seems that the crank is in good shape an I will be able to reuse it as is I just need to replace the bearings as they were getting close to causing damage. Iâll post more pictures when I can, too lazy to right now 
If you are not going to live at high RPMs, reusing con rod bolts/nuts is fine, and using the main bolts again are fine.
If the 12 has plugs in the crank, itâs wise to remove them and clean out any sludge.
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By âlivingâ I assume you are referring to track use right? If thatâs the case then yea I wonât be seeing a track with this engine any time soon and If I did I would probably want more power so I would have to tear it down anyway. But in the event I want to replace them anyways does ARP make any kits or anything for the V12? or should I just try to get ahold of OEM stuff?
Itâs a good idea to replace the Conrod bolts and there is a couple of mods that take just time you can do while itâs apart.
A simple stress relief on the main bearing caps and removing the weight on the Conradâs.
Both mods are on this forum
Robert Vautin
Prestige & Performance Cars
Factory bolts are more than adequate: not sure if ARPâs bolts for the 12 have the same issue as they do on the 6. (Or even if the same bolt)
In any case, using ARPs for the street is a solution looking for a problem. I have no problem with ARP, but for a streeter, itâs expensive overkill.
Thatâs what I figured, I like to follow the logic of KISS as much as possible. I have even seen people reuse torque to yield bolts before on other engines ans then proceed to beat the piss out of it pouring 20lbs of boost with no iâll effect⌠aka the LS engine family.
Alright small update, I have managed to put a âloveâ mark into one of the heads right on the combustion chamber sealing ring. I measured it with a dial gauge very roughly and it appears to be a little less than 0.003 deep at the deepest part and closer to 0.002 at the deepest on the combustion chamber sealing surface. I was/am planning on leaving it and just use some copper head gasket spray, I figure itâs small enough that the head gasket should compensate for it. But i figured I would post here to see what you guys think?
Edit: the picture makes it look deeper than it is, I can only barely catch my finger nail on it in the sealing surface.
There is a high temp mastic for wood burning stoves and fireplaces, resists to something like 1200 C°.
When it dries it becomes hard and you can sand it flat.
As it will be completely covered by the head gasket I think it it will stay in place.
I have tried it to glue a couple of fire bricks inside the chamber of our stove and many years later itâs still intact.
Good to know iâll check it out! thank you!
After some research I have decided to try some JB Weld Extreme Heat. It is rated for 2000F and can be sanded or machined. I am confident that this in combination with the copper head gasket spray will be sufficient in sealing this damage. I plan to run this engine on an engine stand first before putting it in the car so if problems do arise it should be fairly easy to take the heads off and get them resurfaced if needed but I highly doubt it will be an issue especially for a road going engine.
Good luck: tried that onceâŚcar was back in the shop within a week.
My suggestion? Do it right and have it surfaced.
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