Nice, this is my old engine. But I have to correct you. Repair did not cost much at all, moneywise. Regarding time... a bit more.

I fixed this using an AJ6 engine and delivering this old block to the scrapyard.

the AJ6 was cheap though, especially after selling extra parts from the donor car I even made a little money. You just have to be into that... :-)

I think this particular crack could be seen without removal of the cilinder lining, and I bet you won't remove this so you will never know. Just replace the head gasket, and keep going!!!

 

Thanks for the info Ken, exhaust manifold and flanges will be a breeze. System was rebuilt a short time ago.(4 weeks)

 

Ah, then Clarke, you will do this on yer ear, in a full tuck position with both wrists handcuffed and a cute sweety blowing in yer ear just to keep you distracted . . .

Agree with all beyond my post. Crying shame to rebuild without thinking what else you might do. Just beware the trap I first fell into in 1968 with the 2.4L in my avatar. Cold winter nights in Lithgow, little else to do (sorry Chris) - ex ARDC race driver as local Speed Shop owner, mate of Bob Jane's and besotted Jaguar nut . . .

Next thing I know, the engine is bored and stroked to near 3.0L with 10.5 cr, D-Type high lift cams, straight port S gold top head and triple SUs in place of the quaint twin Strangleburg downdrafts. Never as agile as the later saloons, especially in the non-irs rear end, nevertheless with electric o/d disengaged, it could "post" the tacho beyond the red in any of the lower 3 gears.

So Clarke, first fix the head/head gasket; replace valves, guides and seats as needed. These engines breathe fine so bigger valves are no huge benefit. Higher and sharper lift cam grinds will boost power, but watch out you don't overplay the i/o overlap. Aim no higher than the proven competition specs, or lower rpm tractability will suffer badly. By comparison, easing both the induction side for cooler and greater airflow is a plus. Never underestimate under bonnet engine heat soak - a significant loss of power.

So also, you can find benefits in freer flowing exhaust systems. In other than supertuned high revving Jags in my speedboat and hydro days, extractor systems always proved impractical on Jaguar saloons. Even most of those hydro engines were turbo'd into twin water fed megaphones that would frighten the neighbours if fitted into cars. On the other hand, straight through pipes with tubular silencers (sic) front and back (Berkeley were all the rage) can uncage the beast.

So, to summarize, remove head; inspect, repair, skim and true head; replace valves, guides and seats as necessary or regrind faces, seats etc; fit new camshafts or regrind as required; then focus on air induction and exhaust.

. . . and 2 parting shots I overlooked. (1) You mentioned welsh plugs and so did I. Replace the buggas. First R&R I ever did, I overlooked them and was back within 3 months to replace the one most hidden and leaking under everything you will have off - not funny! . . . and (2) use a judicious amount of the all new whizz bang joint and thread sealant on all your head, manifold and exhaust studs - but NOT on your carefully tensioned head and camshaft nuts! Just because you have had all that fun dealing with a busted stud, doesn't mean you will enjoy a repeat!

Take pics, then laze in the admiration of lesser mortals who thought it too hard.

Ken

 

The head will be sent to a very reputable shop for them to weave their magic.

If the block needs any attention we will probably engage the services of Murray Scoble

Home - Peninsula Jag We are planning a forum visit to his workshop, hopefully as our next outing

Pretty much keeping everything stock though.

 

I like Ken's write up. I may have a job to do when it gets warmer! How do you tell a long stud engine from a short stud? I have a 1976 Series 2.

 

According to the article below my engine is from a 75' or later series 2 going by the 8L engine number.
I am aware of another member who has recently purchased a short stud block to replace his long stud block. I will see if I can get him to post some pics of both to clarify.

 

Thank you, Ken.
(';')

 

Thanks Clarke.

I will stop looking.

Somewhere in the "library" is the engine number change point, but that 8L is S2, and all S2 4.2 were long stud engines that I remember.

I have an engine from the daughters S2 under the bench, and I will look at it later tonight and see what is what. I think it "pulled" a liner??. She got is as a 5cyl special, knowing I had a recon engine under the same bench, which she fitted to said car, and Dad got the left overs. She worked damn hard doing that install, AFTER she put the engine together herself.

 

At GREAT expense to management I put down the drink and went looking at this damn engine in the shed.

From the top face of the block TO the top edge of the welch plug hole is 4" to the mark. Being they are a 1 5/8" welch plug, the 5" to the centre of that hole is close enough.

This from a 1977 S2 and is a LONG stud engine.

I forgot how bloody heavy these suckers are, I need a LONG drink now, "on ya Clarke".

 

A quick measure as good as I can with every thing still attached gives about 4" from the top of the block to the top of the plug. The plug itself is just a gnats dick over 1 1/2".

So I assume now it a long stud engine.

Grant, go have well earned JD.

 

Just found the original engine #7L706254-S, so with the 8L engine it certainly has had a heart transplant.

So now hoping it was rebuilt before it went in an possibly no seized studs.

 

I knew it was somewher, so I copied my TERRIBLE scribblings into a word doco.

Jaguar XK engine decoder.doc

If there are hiccups, so be it, thats all I have.

The V12 stuff is also there and I will scribe that when I feel like it.

ENJOY.

 

For many, the following summary may help . . .

From Clarke's post #26 . . .

Short Stud -
". . . studs screwed directly into the block face." So, after the first stud rotation when extracting, you will see stud thread starting to appear.

Long Stud -
". . . the cylinder head studs screwed directly into the base of the block, through the waterways and, if the correct coolant is not used, then they will rot out very quickly. These studs are also twice as long as the pre-1968 blocks, allowing more stretch and therefore more variation in clamping pressure against what has been set with the torque wrench and this makes it more prone to head gasket problems." So, after the first stud rotation when extracting, you will NOT see stud thread starting to appear.


The early XKs, even the 4.2L, may now be seen as more forgiving in one critical area - not just the initial tension down of head nuts, but the mantra of check and re-tension at 1,000 miles after any R&R head. Our mantra went even further (1) tension and check on assembly (2) check and re-tension after running to normal temp, test drive etc then (3) check and re-tension after 1,000 miles or 1,500 Km - as well as re-check of valve clearances.

Two points are worth emphasizing for those new to the task -

• by design, tensioning or re-tensioning head nuts has no effect on valve clearances; this being counter-intuitive for those more familiar with OHV rather than OHC;

• while everyone rightly focuses on perils of stud corrosion in later XJ "long stud" engines, with due care and armed with knowledge, WD40 and patience, disaster of stud breakage can be avoided;

• spoken of all too briefly, is the real hazard here - that these far longer studs can (and do) stretch so that mantra of re-checking and re-tensioning is sound advice.

Gaining access to ALL the head bolts is not difficult - and a quick job with medium or long extension. To gain accurate results with a tension wrench, wipe any surplus oil off the threads (studs and nuts) - NEVER add oil - set the tension scale ACCURATELY - and NEVER tweak up "just a tad more" after the tension wrench has popped its indicator button.

IIRC, Jaguar workshop manuals were silent on the engine temperature at which head bolt tensions were set. Strange, and different shops advocate different approaches. Normally, we assembled initially at ambient temp (in Oz, this can vary from a balmy 40C down to an arctic 20C, ).

More importantly, once fired up to normal engine operating temp, checked and OK'd, we sat car, bonnet shut to get good heat soak, but allowed to cool for 30 minutes (no-one likes working on a HOT engine). By that time and with bonnet up, engine was still warm to touch and tension checked and adjusted in sequence.

Hope this helps,
Ken

 

Dr Phill and myself just shared a few bottles of amber happy juice and a look at the car,manuals etc working out a plan of attack.
It's looking like pulling everything down Sunday, getting the head off to the shop Monday an go from there.



Phill worked with the PO for many years at a Toyota dealership so he made a call to see if there was any info on the engine. Nothing touched in that dept, just the IRS and rack bushes were touched......gets me wondering about my IRS debacle

Questions we came up were:

1.Does anyone have a run down on doing upper timing chain removal and refit. Is the tensioner tool essential? We can fabricate one from the dimensions in the manual if we need to.

2.Cylinder head bolt tension. Is there a modified tension for the Payen(Monotorque gasket)?

3. Do these cap nuts give any indication to what studs lye below?

 

Hiya Clarke,

(1.a) Nope, but as per my write-up, I would avoid a general dismantling of ALL the upper t/c unless there is obvious badly "scalloped" wear on cam gears. We start with plugs out and rotating engine to #1 TDC. The upper t/c idler/tensioner has no timing significance so get it out and away. Now, we have 3 gears - the bottom/upper transfer gear and 2 camshaft gears - all 3, together with t/c have timing registration or indexing marks. Those on cam gears should be easier to see. Use wire to fix loops of t/c to gears. Remove cam gearwheels with t/c wired on. DO NOT ROTATE ENGINE BEYOND THIS POINT.

Then with top idler gone, reach in and wire t/c over the bottom/top transfer gear so that it too cannot slip mesh. Now drop cam gears+t/c and they will centralize, partly overlap, and cam bearing half-shells, camshafts, buckets and shims removed, head lifts straight up and off. Watch for 2 drop-in annular locating rings at either end of block/head mating surface - knowing they will be there is the secret key to getting the head off - pointless banging it sideways - aim your blows with rubber mallet UPWARDS - one at back, then front, then swap sides and repeat.

(1.b) Yes . . .and No . . . and Yes. But as you have already hinted . . .

(1.c) Given the dimensions in manual, they are easy to fabricate and give a known, reliable timing. Get some of your Brissy XK/XJ mebers together; get them to make 10 and take 1 each - essential piece of DIY kit for about 30 years plus of Jaguar engine overhauls.

(2) I have absolutely no idea or can't remember. You need Grant on this!

(3) Good try, Clarke - but the answer is absolutely NO. Having said that, please don't sweat the head nut removal - rarely if ever a problem in my experience. Remember, WD40 and patience - but even these are more in the province of head STUD extraction.

Cheers,

Ken

 

Questions we came up were:

1.Does anyone have a run down on doing upper timing chain removal and refit. Is the tensioner tool essential? We can fabricate one from the dimensions in the manual if we need to.

2.Cylinder head bolt tension. Is there a modified tension for the Payen(Monotorque gasket)?

3. Do these cap nuts give any indication to what studs lye below?

Attachment 125638[/QUOTE]

1) Slacken the locknut on that serated wheel, push the plunger IN with the finger, and rotate that wheel with a pair of SHORT pointy pliers, one point in each hole of that wheel. This will slacken the top chain, and that is ALL you need. Retighten to "firm" when replacing everything. If that top chain is too tight, it will "whirr", but I doubt you will get it too tight with pliers. The correct tool can do so in a heart beat.

2) Not that I am aware.

3) NOPE.

 

FORGOT.

DO NOT rotate that engine backwards.

If you go past some timing mark or whatever, go round again and pay better attention this time.

 

Just to throw a spanner (or idea) into the works. If your head needs reworking anyway you could consider getting a head from a series 3 with the bigger valves. Might even be in a good condition so you don't have to send it to the machine shop, just rebuild it (Might even be cheaper).....unless you want to port it.....then fit triple webers (just because they look awesome your HS8s will do fine)....then......

 

S3 heads down here are as rare as honest politicians.

Corrosion killed many a very long time ago.

 

Well an honest politician is an oxymoron (in more ways than one!!), Whereas good S3 heads exist somewhere on the planet!!!

You could just have the S3 inlet valves fitted.