Hi Richard
Glad to hear you’re making progress!
Once you’ve got it clear of the 3/8 studs on the inside, it should get easier! Lots of penetrating fluid and also tapping it back down does help.
If you’ve got compressed air, blowing locally around the studs does help to shift the crap sometimes.
I had one head that simply would not budge on one of the long inner studs.
I got the gap up to about 2" and it’s went solid! I had no alternative other than to cut it off with a pad saw!
When it was off, I got it on our BIG
hydraulic press, it finally surrendered at about 15 tons of pressure!
I doubt that you will not need to have the head face skimmed? You’ll probably find quite a bit if corrosion on the head face? Maybe even too deep to totally eradicate. But as long as it’s only in the areas where the gasket doesn’t seal anyway, a good skim should suffice. From standard, maximum to skim off is 30 thou.
I hate to be the harbinger of doom,but your could be getting the studs out of the block! I hope there’s no great corrosion on them.
Anyway, good luck! Old Jaguar V12s certainly need a lot of patience!
Best regards
Nigel Boycott
Oh what a beautiful morning !
And here is why:
This grey Sunday morning decided on a dose of Jag therapy.
Looked at A head having the 14mm gap.
It took about 2 or 3 hours work to get the first 5mm gap, another 1 hour to get that up to 14mm.
I expected another 4 hours of struggle to get the head off.
However, jacking up the front as far as possible, then jamming packing material into the back of the head, then dropping or hammering the front down again made great progress.
That allowed the head to see-saw about the fulcrum point of the 2 or 3 sticky studs in the middle.
After an hour the head is nearly off. Might take another 30 minute to an hour and it should be clear.
Bravo Richard, hope you find what you were after with the removal of the heads.
Please share any and all thoughts on the procedure and what you find. Is this an engine that was dry (no coolant for years or still traces, etc.) HE or PreHE…how the studs appear, etc. Thanks for sharing this most arduous experience, my cup of Single Malt held high in you honor. Best, JW
You know the feeling as it gradually dawns that perhaps you made a bad decision ?
I am getting it now.
The A head is off, took another one and half hours.
Once the head was close to release it was hard to get any leverage on the back end.
It looks like most of the trouble was the main stud between 3 and 4, incredible how tight it was up to the last fraction of an inch.
There is impact damage on cyl 3, something dropped in there at one time.
A lot of erosion, about 3mm deep between 3 and 4.
Noticed rust spots on the cylinder wall of 3. One feels deep enough it will not clean up when I have the liners honed, and it looks like it will be low enough in the bore to contact the rings.
A quick and light wire brushing of the head to get the carbon off shows lots of spotting on the sealing surfaces, but no sign of pitting.
There may well be more tales of woe as the bottom end is stripped. You recall when first turning over the engine before doing anything the crank took an enormous amount of torque then suddenly released. No idea or evidence so far what all that was about.
Summing up, there will be far more work and money spent to sort out this V12 compared with the other two I rebuilt.
I will be in U/K early August and I know there is a wrecking business in Derbyshire which 2 years ago had about a dozen V12s with HE engines. At least one belonged to an XJ-S which had a time expired body but was driven into the yard with what appeared a good engine. That is a temptation. Even allowing for purchase of the engine plus rather pricey freight It could get me a long way ahead.
A couple of forum members mentioned freight companies that might give a reasonable price to bring a single engine over from U/K. Next decision is 5.3 or 6L ? I am happy with 5.3, and I have 5.3s in the coupe and convertible plus a collection of spares and ( most important ) tappet shims. Having a 6L means not having 2 running engines plus a spare all exactly the same. Of course 6L engines are a bit younger, but typically around 25 years old as opposed to 30 years old so it is not a game changer. Not sure they have any other advantage apart from a bit more torque and power which means nothing for me.
The head stud problem.
It is too late to fix it for engines assembled by Jaguar. Looking at the head gasket there are sealing rings around various areas to prevent oil or coolant escaping. The rings will stop fluids flowing outwards or inwards along the gap between head and block. Google photos of gaskets show some have rings around the studs in the water jacket, but they do nothing useful. They have the solid head surface on one side and a cavity on the other side. They do not compress to form a seal even if intended to. In any case, they could not stop coolant flowing up the stud hole into the head, they could at best stop transverse flow in the head gap if trapped between two solid surfaces…
How about putting the gasket on the head, then applying a suitable sealant around the stud where it contacts the gasket. When the head is torqued down it will seal the gap which usually allows sealant to creep up the stud hole.
What do you reckon, anybody tried it ? It might not help you, but if the car and engine last long enough there will be a day when the heads need to come off again.
I need a wine.
Correction:
I said:
How about putting the gasket on the head, then applying a suitable sealant around the stud where it contacts the gasket.
I should have said "putting the gasket on the block ".
That was before having the wine. I feel better now.
This is the A head.
Ran over it with a wire brush, then on the back 3 cylinders gave it a quick workover with fine wet and dry paper.
So far it looks as if the all the firing rings are good, and they do need to be 100%.
In spite of the erosion in the water jacket area the sealing surfaces look good too.
Provided close attention is paid to the actual sealing of the water jacket a small amount of compromise can be tolerated.
The pressure in the jacket is nowhere near what you get in the combustion chamber.
The eroded area looks terrible but it is in the jacket area and not critical to the functionality of the head.
The #3 cylinder had part of an M3 or M4 screw embedded in it plus numerous dings. Likewise the top of the #3 piston has a few dings to match. There is a pattern of much smaller dings in the #1 cylinder head, no doubt fragments from the screw got into there also. I could dress up these areas by hand, however since I usually take such dirty heads around to the local engine reconditioner to drop in his cleaning tank, I might get them skimmed to clean up the dings.
If there were no dings it looks like the head surface would be fine with just a clean up using wet and dry to check for any scratches that could cause a leak.
There is yet to be explored what we find when the valves are removed, and what the B head yields in the way of problems. The crank turns over quite easily, so for the moment just oiled the bores. The pistons crowns are filthy and depositing crap all over the bores. That needs cleaning before a close inspection, but up till now cannot see any major trouble apart from one rust spot.
The engine is capable of being rebuilt, hopefully with no unpleasant surprises along the way.
There was a time it looked a bridge too far.
Richard
S&G Barratt recently had a very good offer on HE V12 heads the ones I got even had new tappet blocks. Both arrived in OE factory boxes and wrapped in wax paper! I think they were around £420.00 for the pair?
Sorry SNG Barratt! Damn I phone keyboards!
Well done Richard!! They can be a challenge!!!
I think the 5.3 has a forged crank and forged rods and the 6 litre has a cast crank and unsure about the con rods. The bottom end is possibly stronger on the 5.3 …plus you already have two of 'em.
When you remove the big ends would you be able to check if there is any difference between the top and bottom shells. I had 12 showing copper and 12 with white metal sitting on the bench when I removed mine but didn’t notice this until I was cleaning up so I don’t know which came from where …and I am wondering If there is a top/bottom or end for end thing going on…??
I’d be curious to know how yours look.
Regards
Matt
The only way I have had success with V-12 head removal is to use at least five of the tools made from the drawing in Kirby Palms Book. The tools push directly against the crudded up head studs and are bolted to the cam bearing cap studs.
I can state categorically there is no way the heads on this engine could be lifted with any kind of jig or tool relying on the tappet studs.
At a guess it needed at least 4 times the tensile yield of all those studs together.
Not to worry, they are off now.
Next thing is to take the valves out and see what is revealed. I know there is a broken valve guide in B1.
Richard
S&G Barratt recently had a very good offer on HE V12 heads the ones I got even had new tappet blocks. Both arrived in OE factory boxes and wrapped in wax paper! I think they were around £420.00 for the pair?
That sounds very cheap for new heads Nigel.
Are they 5.3 heads ?
Are they reconditioned heads, or new heads as well as new tappet blocks ?
Of course, if Barratt or their source have a stock of them what else can they do but sell them at the best price they can get.
Hi Richard
Yes I can confirm that they were brand new as were the tappet blocks and tappet block studs included. A VERY good price!
Yes 5.3 HE heads I couldn’t believe it either but certainly did when they arrived. Also required very minimal seat grinding!
If of any use to you Richard, l imported my 6 litre from UK several years ago through a land rover business here in Australia as part of one of his containers. He handled all aspects of the import and from memory it cost me around the $1K mark into Melbourne. Can’t remember what the motor cost but all up including freight was under $3K.
Nigel,
Barrett still advertise LH & RH cyl heads for GBP400 the pair.
I have not checked if they still actually have stock, and they mention the same parts for GBP540 the pair so that is confusing. No mention they have the tappet block fitted.
There are U.S. sites with similar deals and varying prices. and one shows a cylinder head including tappet block.
I partly cleaned up the B head and can see a ding on the fire ring on one cylinder.
It looks marginal to clean up with a skim, and knowing it has at least one broken valve guide it looks like the Barrett deal will be a long way ahead of my time and money spent to clean up and fix these two existing heads.
I can drive over to the Barrett factory while in U/K and get a few other items needed.
The timing cover on this engine has a small crack legacy of the PO’s collision.
Might pick up one of those in U/K too.
First need to strip the block and make sure the rest of the engine is o.k.
YUP!!!
I don’t even try. As for me the world is safe from a text and drive, Me. My phone is dumb, anyhow…
Carl
This V12 is so filthy inside. After draining oil from the sump I poured 2L of diesel fuel into the sump and left it for a week.
That made a much better job of a second draining before starting on the bottom end.
This engine had a chequered life. Apart from the PO crashing his XJ-S, he or somebody did sloppy work in the sump area.
The steel sump pan and the sandwich plate look o.k., but inside the rectangular baffle around the pickup screen is battered.
The rounded head of the pickup screen is creased and dimpled by impact. What the …?
The baffle is usable but it offends the senses to put that back in the engine.
If anybody is pulling apart an old engine for spares I am interested. The timing cover has a crack in it too, legacy of the PO’s crash.
I went to SNG Barrat’s UK website and emailed to say interested in picking up a pair of heads and overhaul gasket set when in UK 4 weeks from now. So far no answer. Business must be booming so new customers can be ignored ?
More likely their website based email messaging is not serviced. I detest that kind of emailing since you do not have a copy of the message on you own email system, and the messages are quite often ignored.
The crank spins o.k. so next exercise is to strip everything including the liners out of the block. There is maybe 3 hours available each week for this work so it will not be finished for a while.
The uploaded photo in previous posting was clipped - no idea why.
Might have been the size, it was nearly 2MB
This one is 500KB, that could be the issue.
The original photo has also been turned through 90deg.
Seems like the uploading program does not tolerate photos taller than they are wider.
Interesting. Just more of a challenge, eh wot!!!
I’m a bit fuzzy on just how I do it. I click on the picture. it opens, I think I open it, and then iit appears in a mode that I can 'mess" with it. Naah, just edit, not photoshop or anything complicated.
It can then be rotated or with zoom expanded, etc.
Kind of fun…
Oh, over the decades, I’ve opened far worse…
Carl