If you google "jaguar v12 head puller" and choose images there seems to be a number of static shots of the two plate design in use. For what it's worth l can't see what the two plate would do that the single can't. It still attaches to the head in the same manner and pushes against the head studs in the same way.

 

Hi - this is Neville.

I found some text from an old post but the images are missing. I will post them as soon as I find them.

In the meantime, here is the text ...

Here are some pictures showing how a home-made device can be used to easily separate V12 heads from the block.

Having studied Kirby Palm's excellent technical summary of the V12 (downloadable for FREE from http://www.jag-lovers.org/xj-s/book/XJS_help.pdf), and having listened to some tales of woe from others who have struggled vainly to separate the heads from the block, I decided it would be well-worthwhile making up a device to simplify head removal - particularly as I have at least two engines to rebuild. Also, when I went to collect this engine, I was shown a block where one head had been completely removed and the second was stuck fast - even though there was 3 inches of fresh air between the head and the block. The owner had tried over many months to separate the second head (without the benefit of "The Beast" but all attempts had failed. He was even considering having a hollow reamer made that he could slip around each stud - but I suspect this is "clutching at straws". Perhaps, if I am feeling generous, I may pay him a visit with "The Beast" in tow.

I have probably spent more time making up such a device than actually working on the engine, I feel it was time well-spent! I have christened the head-removal device "The Beast" because of its size and weight

I must add here that I have become an avid reader of the V12 forum on the "Jag-Lovers" website. Over the last few weeks I have learnt much about the V12 from its contributors - many of whom are very experienced in Jaguars in general and the V12 in particular. I unhesitatingly recommend you subscribe to this forum if you are contemplating a V12 rebuild - the members there are invariably helpful and willing to pass on the benefit of their experience. You can visit Jag Lovers by clicking HERE.

The engine

The "flat-head" V12 in the photos had been stored in various garages/lock-ups for the past 20 years or so. I was told it was removed from a XJ12 saloon. Because of its history, I was anticipating difficulty in persuading the heads to leave the block .... The first thing to greet me when I came to remove the head nuts was just how many there are! Having been used to the relative simplicity of the XK 6-cylinder iron block, it seems I will have to develop the patience that is needed for "12 of everything" .. or should that read "24++ of everything"? Of course, it is important to remember to remove ALL the nuts holding the head down - including the ones attaching the head to the top of the timing-case. "The Beast" is more than capable of pulling a stud out of an alloy head if a nut is left attached.

Incidentally, I discovered that there is no need to make up a special tool to hold the camshaft sprockets in place during head removal if you happen to have a couple of suitable external circlips. I found that by placing circlips into the grooves already machined into the end of the sprocket spindles, the spindles can simply be dropped over their respective retainers. There is also no need to slacken the chain using special tools if you simply fasten one of the sprockets to its holder so it remains out of the way while the head is removed.

"The Beast"

"The Beast" is fabricated from two sturdy 3/4" steel plates. The top plate fits over a series of threaded bars that are welded into the bottom plate.

Step One - attach lower plate.

Place the lower plate on the head so that the camshaft locating studs protrude through it. It can then be fastened down using the original nuts and washers. Please bear in mind that this is an alloy head and do not over-tighten these nuts!
As can be seen in the next photo, the studs at the front of the engine are in different places left to right. The plate covers all the camshaft studs on the left-hand head, but misses the front pair on the right-hand head. If I was to make another bottom-plate, I would add extra length and holes to accommodate this left-to-right difference..

Step Two - add steel rods

Drop the rods (I used stainless) through the bottom plate so that each rests on a cylinder head stud. The diameter of the rods is slightly smaller than the cylinder head studs and they are chamfered to facilitate them following the studs through the head.

Step Three - place upper plate

Place the upper plate over the threaded bars and, using the small socket-head screws, level it making sure all the stainless rods are in contact at both ends.

Step Four - fasten upper plate

Check the plates are parallel to each other and fasten using long nuts/washers on the threaded bars.

Step Five - remove the head.

Remove the head by tightening each double-nut the same number of turns, in rotation around the upper plate. The whole operation took under an hour for each head and required very little effort - in fact, it was quite therapeutic and satisfying to see the head gradually slide up past the studs. The hardest part (once the head was lifted almost clear of the studs) was lifting the head complete with "The Beast" off the engine.

 

Good to hear from you, Neville.

How's your glorious quad-cam? I still remember the day you started it up at the London Classic Car Show, much to the annoyance of many of the organisers! Wonderful!

Paul

 

Neville,
Thank you. That was exactly what I needed. I am having fits with the single-plate tool and am perhaps hanging too much hope on yours but hope springs eternal none-the-less. I am working on an '89 XJ-S. The A-Bank head needs to come off. So far the single plate managed to strip the nuts off four cam studs. The head has moved but not evenly. The rear comes up rather easily but I cannot get the front to raise at the same rate. I keep hoping I missed a fastener but cannot see one (yes, I got the three nuts from in front of the cam sprocket housing).

My machinist hasn't got to work on my two-plate yet But hopefully soon. Thank you again.

 

I don't wish to send negative vibes your way but....if stripping cam stud nuts is the problem how is Neville's going to give a different outcome. The attachment to head seems identical.
Have you been able to lift it at all at the tight end. If so sliding a decent flat bar through between head studs and bolting it to matching bar across puller may relieve some of the tension on cam studs.
I have one head on the go at the moment using this method (10×50 flat bar) but it is still putting up a good fight. Snapped 4 cam studs getting it up far enough to slide through.

 

Your point is well taken. Having never used Neville's tool it is hard to form an opinion but it appears to me the double-plate would have (note past tense) allowed me to notice the uneven pull sooner...maybe not. Perhaps there is a design that would incorporate the intake studs and/or the 5 studs up by the timing chain which would spread the stress out. If you use a stud puller to take out the studs and tread a long 100-110mm, 8 X 1.25, you eliminate the possibility of the cam stud nuts stripping but the bolts can still break...ask how I know

With the benefit of hindsight, I regret not doing some of the prep-work that was recommended by another contributor. By that I mean I ignored advice to put a sacrificial nut on each stud and using an air-chisel, rattle each until there is side-to-side movement and penetrating oil flowing through. Having now done several, I can see the difference those that are loosened up by the vibration and those that are not. I am down to four stubborn remaining studs that have yet to submit.

 

Since I had the head "tilted", I decided to bolt it all back down to level by tightening the rear half head nuts. That turned out to be almost as hard as getting them off and lifted in the first place. I also went back with an air hammer and tried vibrating all the studs which will not allow penetrate to flow down the stud. It is a large powerful hammer but didn't seem to have any effect. Then I removed all the nuts and lifted from the front only with a chain and engine hoist. So far, no movement at all on the front end.

I am wondering if anyone has ever tried a stud remover to try and twist them out of the block. Seems like if a stud turned at all, that would allow it to slide through the head. Or what other "drastic " measures I might take if it just isn't coming loose. Open to ideas here Thanks.

 

I have, long ago cut the offending head stud with hacksaw blade, removed the head then driven out remains from head from below. A nut was then welded to remaining stud in block and removed. That all depends on identifying the problem stud/s and being able lift head sufficient to access and cut stud and then stud unscrewing cleanly from block.

 

hi there,
I am new here on the forum and i really need a head puller and i decided to make one myself. I have acces to a milling machine but i am in search of drawings of the head puller.
I clicked on the link but i couldn't find the drawing there. If you are willing to send me the drawing i would highly aprecciate it.

 

I can't seem to PM you Mark. May be a new member limitation. I could email it but again the initial contact to exchange address may be a problem until your time is up.

 

Rough drawing of head puller. This is for captive nut laminate plate design so if tapping directly the hole sizes need to be suitably modified.
Edit. Not sure what happened to pic started off clear enough. I will try for an improvement.

 

Hi baxtor,
I think this picture is good enough for me because all the measurements are present. Thanks a lot!
Im going for the single plate design and using a slightly thicker plate of 12 mm, so im pretty sure this will work for me.
I think you are right about the problem with the pm's because i couldn't pm anyone else either. must be a newbie thing.

Kind regards,
Mark

 

Having FINALLY removed the "A bank" head which included the breaking of one engine stud I was informed by my machinist that the corrosion depth renders it "beyond repair". He is a good machinist but has no experience with the V-12 so, I am looking for some specifications that would either confirm or deny his assessment. Anyone know how much can be safely milled from the head?

 

Do you still have the tool for rent? I'd like to rent it. I'm in California.

 

Dtonell if you are a member (or Join) JCNA (Jaguar Clubs of North America) you may loan the tool for shipping costs. Tool travels a lot so FCFS.

 

Theres one for sale on craigslist in Vancouver BC

https://vancouver.craigslist.org/sea...0tool&sort=rel

 

hi,
need to pull the head on my 72 xke. anyone have one to sell or rent
thanks
mike

 

rtr4fun if you are a member of JCNA or a Coventry Foundation patron you can borrow the tool--no rental you just pay the shipping and handling.

 

thanks! just printed the application for the club located in NJ. Once I become a member what is the process for borrowing tools? who do I contact?
Mike

 

Mike once you have a member number you can use the tool loan program. Go to www.jcna,com and read about the use of the tool program.