We are putting things back in place and confirming the order of the dome nut and washer as well as the engine lifting bracket.
Is the washer in correct placement in this picture. Confirming the washer goes “on top of”, as opposed to below.
Thank you.
Candiece,
The attached picture shows the “correct” arrangements of the dome nuts, washers, lifting brackets, and spark plug wire conduit as I installed them in my 1969 E-Type FHC.
Paul
Thank you for confirmation.
Question!
Are the 2 studs which carry the lead tube brackets slightly longer than the others to stop the nut bottoming?
Looks nice, though! 
I have no idea. (?)
Plus 20.
Washers (4x) on the studs with the engine hoist brackets were a bit thinner, and chamfered, on my 1970 S2.
Paul,
This original matching numbers engine was delivered to the machine shop for a rebuild in early 2021 with the cylinder head in the correct unpainted state for a 1969 E-Type FHC. The machine shop has been rebuilding Jaguar XK engines for decades and has a very good reputation. When they delivered the rebuilt engine and offloaded it from their truck It was covered in plastic. When I removed the plastic I was quite surprised to discover that they had painted the cylinder head gold. I never discussed painting this cylinder head like I had with the Duck Egg Green cylinder head for the engine that they rebuilt for my 1957 MK VIII. I was on a tight schedule to get the car running again so that I could move out of California last summer, so I left it the way it was, at least for now.
Paul
Wardell,
All Jaguar XK engines have 14 cylinder head studs. However, those studs come in a variety of lengths depending on the design of the block and the kinds of lifting hooks and brackets that were used for each configuration. All of this is spelled out in the Parts Catalogue for the particular model and year. I don’t have my parts catalogue handy, but I am pretty sure that the four studs for the lifting hooks are the longest, then come the ones for the spark plug wire conduit, and then the rest. I seem to recall there were actually 4 different length studs in this engine.
Paul
Purely from a machine design standpoint, the washer always goes next to the nut, to provide a uniform surface and friction characteristics, important to getting the correct torque.
From a stud length standpoint, 2 things are important. There should always be more depth of female threads in the nut than there is stud protruding, to ensure that the end of the stand doesn’t jam into the nut and give a false (and low) torque reading. On the other hand, if the stud has a nominal diameter of say 1/2", then one would want a minimum of 1/2" of thread engagement of the stud into the nut. We break this down generically to say that “one diameter” of engagement would be an absolute minimum and “one and 1/2 diameters” is optimum. So don’t get too hung up on the length of the stud before you install it, the bottom line is once you get everything assembled you should fall in the range discussed above.
Still looks good from my house!
I’m gonna paint the Jee Type head gold, even though it wasnt specced for that year Jeep…
Thanks. I removed my spark plug conduit and and got the impression that one of my nuts was bottoming when I replaced the head. The lifting lug studs are obvious, but the rest all looked the same to me except the dowel stud. Perhaps not!
Wardell,
What year and model Jaguar were you working on and was the engine the one it came from the factory with? At this point lots of engine blocks, cylinder heads, and studs have been swapped around. I have done my share of that over the past 22 years.
But the block and cylinder head on my 1969 E-Type FHC are original and correct.
Paul
Unless I’m wrong, on the 3.8 engine all the studs would have the same length and the washers would have a D-shape except the two circular and thinner washers that are accomodating the attachments of the plugs conduit :
Btw, is it straightforward to unbolt/rebolt/torque only the two related bolts for putting back a plugs conduit (mine is missing, wrong plug caps also…):
I’m not sure how proper it is, but I’ve done that in conjunction with using/removing the hoist points with no adverse affects.
A couple of comments, and one warning:
According to the Parts Lists, the 3.8s had 10 “D” Washers under the dome nuts, and 4 round ones. The round ones were used where the plug lead conduit was attached and also at the front 2, where the profile of the cylinder head doesn’t permit a “D” to be fitted.
The S1 4.2s only had 6 “D” Washers under the dome nuts, and 8 round ones. The round ones were used for the plug lead conduit (2), the front 2 (2), and both ends of the engine lifting brackets (4).
The engines fitted to the Series 2 cars had no “D” washers under the dome nuts.
If you have a long stud 4.2 block (introduced some time in 1968 I believe, which can be identified by having 5 freeze plugs on the exhaust side), you may want to reconsider fitting the plug lead conduit by removing the 2 dome nuts. More than one person has started out on the 30 minute cosmetic upgrade, only to have the dome nut not release from the stud, but instead cause the corroded stud to shear off at the bottom of the block, and result in an expensive engine out project…
-David
David, I agree completely with you not to disturb the nuts because of the associated risks and have said so on past posts. I would not do it. Having said that, I do wonder if the stud is already that weak that loosening the nut would break the stud, maybe the studs are that weak that they ought to be replaced???
Tom
Very informative David, thank you.
I had noticed the 10 + 4 D-shape washers for the 3.8 in the spare parts manual, but I was actually wondering where the 2 circular (additional to the 2 for the plug conduit ones) were located (I had not looked in detail on the engine).
It was not easy to find in the manual because oddly the parts are not identified in the engine head drawing…
Btw, very good warning for the long stud 4.2 block.
I agree, but “ignorance is bliss” applies in my case…
