Twin-overhead-cam straight six built from 1949 to 1992, from the XK120 through the Mk2, XK150, E-type, Mark X, 420 and the XJ6 Series 1 to 3. Little of the engine was painted: the iron block was black, the alloy head was coloured by engine size for a period and then left bare, and the cam covers were polished castings before they went black with bare ribs. Most restoration mistakes on an XK are painting something the factory left bare, or polishing something the factory only buffed.
Also known as: XK engine, XK6, Jaguar twin-cam six
The record stops at 1952 because that is where the judging guide's own section heading stops: the semi-gloss black list is given for the nitrocellulose-painted Foleshill cars and the guide does not repeat it for the synthetic-painted Brown's Lane cars from December 1952. Nothing found suggests the block itself changed, and the separate record for 1957 to 1971 shows black continuing; the honest position is that the sheen is documented for the early cars only. Model years against the XK120 are the model's own span from Wikipedia. The Frost product is named for Jaguar and is semi-gloss black, but its RAL 9005 reference is the modern paint's, not a Jaguar reference, and nothing has been measured.
Sources
judging-standard:JCNA, Jaguar XK120 Concours Judging Guide, Corrections and Updates (second printing), Appendix I Paint Finish — Lists the engine block among the mechanical components finished semi-gloss black whatever the body colour, because polishing lacquer took too long to extend it to them; the list sits under the heading for nitrocellulose-painted cars built at Foleshill from 1949 to late 1952 and is attributed to Urs Schmid, XK 120, volume 2, page 174
forum:Jag-lovers Forums, XK section: Engine Block Colour — Owners report finding only black paint on blocks they believe original, one of them on an XK150 block, and none of them reports a block in any other colour
None of the three judging guides states a sheen for the block, so gloss is entered as this site's default rather than as a sourced fact; the XK120 guide is the only one that commits to semi-gloss, and only for cars up to late 1952. The record stops at 1971 because that is as far as the fetched judging guides reach. No source was found for the block colour of XJ6 Series 1 to 3 engines, 1968 to 1992, and none has been assumed here, although no source found suggests it changed. Model years are each model's own production span from Wikipedia. The modern matches are general engine blacks, offered in gloss and satin because the sheen is not documented.
forum:Jag-lovers Forums, XK section: Engine Block Colour — Owners who have stripped engines they believe original report black and nothing else, including on an XK150 block; one notes that a red block would photograph as black in period monochrome images, which is how the red claim survives
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
The B-type head arrived around 1954 and brought colour with it on the saloons, so a late XK140 in the applicability list is only bare if it has an A-type head. The XK140's own years are the model's production span from Wikipedia. A bare head that has been media blasted looks nothing like an as-cast one, and a judge can tell.
community:Wikipedia, Jaguar XK engine — Describes the earliest Standard or A-type heads as identifiable partly by their unpainted aluminium finish, and dates the B-type head to around 1954
Awaiting measurementC · Community consensusDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
Two points are open. First, whether the handful of XK120s fitted with a C-type head were red: an encyclopaedia entry says XK120s and XK140s with C-type heads were painted red, while a long-standing XK researcher on the XK-Lovers archive says he can confirm the XK140s but not the XK120s. Second, how much of the head was red: one researcher says the paint ran the full depth of the plug valley up to the cam cover gasket joint, and also reports heads on which it covered only the valley and not the peaks, ends or manifold faces. No factory document, parts book or club technical page stating either was found. No shade, code or standard reference for the red was found anywhere and none has been guessed.
The C-type head was the SE in the UK and the MC in North America. Model years are each model's own span from Wikipedia. Finish recorded as gloss because no source states a sheen.
Sources
community:Wikipedia, Jaguar XK engine — States that a very few XK120s and XK140s were supplied with the C-type cylinder head and that it was painted red
forum:Jag-lovers Forums, XK-Engine: Cylinder head painting — Roger Payne, who researched the XK140 for a book, says the red on a C-type head runs the full depth of the plug valley up to the cam cover gasket joint, and that coverage varied, with some heads painted only in the valley
Light green, also called duck egg blue and duck egg green
XK 2.4 and 3.4, B-type head · 1957–1967 · head, gloss
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
The colour has three names in the sources and it is not settled whether they are one colour or two. A JCNA judging guide and the S-type Register both say light green, the Register adding that duck egg green is the same thing. Wikipedia says the same heads were light duck egg blue on early cars and light green on later ones, which would make it a change rather than a naming variation, but gives no date or engine number for the change. A poster on Jag-lovers cites Jaguar Service Bulletin 272 of November 1959 as saying light blue for B-type heads, which is a factory document but was not fetched or read here, only reported at second hand. Separately, an owner on the same forum warns that what UK suppliers currently sell as the colour is much greener than the original, which he describes as almost white. This one needs an unfaded original head measured before anything is asserted.
Only 2.4 and 3.4 litre engines. The 3.8 is a different colour and has its own record. Model years are each model's own production span from Wikipedia. Finish recorded as gloss because no source states a sheen. No paint code, RAL or BS reference for this colour was found and none has been guessed; the DuPont formula quoted on Jag-lovers is a period mixing recipe reported by a forum member, not a Jaguar reference, and has not been recorded as a code. The Frost tin listed as a modern match is sold as Light Green (Duck Egg Blue), which is both of the names the sources use for this head. Frost does not tie it to Jaguar and nobody has measured it against an original head, so it is a starting point and not a reference.
Sources
judging-standard:JCNA, Mark 2 Judging Guide (2009), Cylinder Head Color — Gives light green for the 3.4 litre Mark 2 head, mid blue for the 3.8 and natural aluminium for the 240 and 340, citing Steve Kennedy's Jaguar, The Classic Marque
club:The International Jaguar S-type Register forum: 3.4 head colours — A register member citing the club newsletter gives the S-type's two factory head colours as light green, also called duck egg green, on 3.4 litre engines and dark or metallic blue on 3.8s, and says the same light green was used on the 2.4 and 3.4 Mark 2
community:Wikipedia, Jaguar XK engine — Says B-type heads on 2.4 and 3.4 litre models were painted light duck egg blue on early cars and light green on later ones
forum:Jag-lovers Forums, Concours: Source of paint, 3.4L XK engine cylinder head, Duck Egg Green — A poster cites Jaguar Service Bulletin number 272 of November 1959 as listing head colours and as specifying light blue for both 7:1 and 8:1 compression engines with B-type heads; another poster in the same thread supplies a period DuPont mixing formula for the light green
forum:Jag-lovers Forums, Saloons: Paint puzzle, cylinder head 3.4 Mk 2 — Owners of low-mileage 3.4 Mark 2s report light green on heads they believe original; one warns that paint sold in the UK for the job comes out far greener than the original, which he describes as a very pale, almost white green
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
All four sources agree the 3.8 head was a metallic blue and that the colour marked the engine size. They do not agree on how dark it was. A JCNA judging guide calls it mid blue, the S-type Register calls it dark blue or metallic blue, Wikipedia calls it metallic dark blue and a researcher on Jag-lovers calls it mid metallic blue. Nothing found reconciles them, and no code, RAL or BS reference for any of the readings was found. Since it is metallic, faded and polished originals will read lighter than they left the works, which may be all this disagreement is.
Model years are each model's own production span from Wikipedia. The Mark IX is named as carrying this colour by the S-type Register but is not listed in applicability because no production years for it were established from a fetched source. Finish recorded as gloss because no source states a sheen.
club:The International Jaguar S-type Register forum: 3.4 head colours — A register member citing the club newsletter gives dark blue, also called metallic blue, for 3.8 litre S-type engines and says the same colour was used on the XK150 non-S, the Mark IX and the 3.8 Mark 2; another member reports South African-built 3.8s keeping metallic blue heads to the end of sales in 1968
forum:Jag-lovers Forums, XK-Engine: Cylinder head painting — Roger Payne says Jaguar used head colour to tell engine sizes apart, with 3.8 litre engines in mid metallic blue and 3.4s in non-metallic duck egg blue
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
XK 3.4 S and 3.8, straight-port head · 1957–1961 · head, gloss
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
Whether pumpkin orange is a Jaguar name at all is contested. The 'E' Type Forum's administrator says Jaguar's records call the colour Gold for the whole of XK150S and 3.8 production, and that pumpkin is a later American label for the flat, non-metallic version of it, the metallic Bradite Old Gold arriving from late 1961. On that reading pumpkin and gold are one colour that changed formulation, not two colours. The JCNA Series 1 guide treats them as two, recording pumpkin heads up to at least engine R-2512 and gold after. Neither position rests on a Jaguar document that was read here.
The upper end of the year range is soft. The judging guide fixes the change by engine number and says explicitly that R-2512 is the highest pumpkin head observed rather than a documented last one, and no source found gives a date for the change, so 1961 here is the end of XK150 production and not a sourced changeover. A retailer, separately, dates the colour 1959 to 1964. Finish recorded as gloss because no source states a sheen. Bradite still trades in Wales but, per the same forum thread, holds no surviving samples or records of what it supplied to Jaguar.
Sources
community:Wikipedia, Jaguar XK150 — An engine photograph caption attributes the orange paint to S models with straight-port heads and three carburettors, and gives the XK150's span as May 1957 to March 1961
community:Wikipedia, Jaguar XK engine — Says the straight-port head introduced later in the 1950s was painted pumpkin orange on the XK150S
judging-standard:JCNA, Series 1 E-type Judge's Guide, Cylinder Head Color — Records early Series 1 heads as pumpkin coloured through at least engine number R-2512, notes that this is the highest example observed rather than a documented cut-off, and says the colour then changed to gold
forum:The 'E' Type Forum: Cylinder head paint — The forum's administrator says the paint came from Bradite and that Jaguar's own records call the colour Gold throughout XK150S and 3.8 production, and that the earlier non-metallic version is what Americans retrospectively call pumpkin
retailer: Paintman Paint, Jaguar Pumpkin Orange Engine Paint — Product page states the colour was traditionally used on the XK150 and E-type from about 1959 to 1964 and that the shade was matched from an original E-type engine; a retailer's claim about the colour, not a Jaguar reference
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
XK 3.8 and 4.2, straight-port head · 1961–1967 · head, gloss
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
Nearest BS 381C
BS 381C 356 Golden Yellow
What is disputed
Three separate disagreements sit on this record. Whether the gold was flat or metallic: the 'E' Type Forum's administrator says Bradite switched Jaguar from a flat gold to a metallic Old Gold in late 1961, which would make two shades under one factory name. When it ended: a JCNA judging guide says late 1967 and brackets it with engine numbers, an owner on the Jaguar Experience forum says colour ended in 1966, and other owners of 1967 cars report bare heads. And how far up the head it went: heads are found painted only to the machined surfaces and others painted right through the valley, and a researcher on Jag-lovers says leaving the machined sections below the cam cover gasket bare is simply wrong. Nothing found settles any of the three.
The BS 381C reference is not a factory reference. It is a suggestion by the 'E' Type Forum's administrator for a modern standard to work from, after he established that Bradite no longer holds samples or records of what it supplied Jaguar. Treat it as a starting point for matching, not as evidence of what left Browns Lane. The 420 and Daimler Sovereign of 1966 to 1969 also used a 4.2 litre engine, but no fetched source states their head colour and they are deliberately absent from applicability. Model years are each model's own production span from Wikipedia. Finish recorded as gloss because no source states a sheen. No UK retail product named for this colour and this marque was found: Paintman's Jaguar Old Gold tag page listed no products when read, Frost's gold engine enamel is not sold as a Jaguar colour, and SNG Barratt's catalogue could not be read.
Sources
judging-standard:JCNA, Series 1 E-type Judge's Guide, Cylinder Head Color — Records gold heads through late 1967 and then a change to natural aluminium, giving the highest confirmed gold head as engine 7E10192-9 and the lowest confirmed bare aluminium one as 7E11938-9
community:Wikipedia, Jaguar XK engine — Says the cylinder heads in the Series 1 E-type and the Mark X were painted gold
forum:The 'E' Type Forum: Cylinder head paint — The forum's administrator says the paint was made by Bradite, that Jaguar's records call it Gold, that Bradite supplied a metallic version known as Old Gold from late 1961 in place of the earlier flat gold, and suggests BS 381C 356 Golden Yellow as the modern equivalent to work from; he also reports that heads have been seen painted only up to the machined surfaces and others painted right through the valley
forum:The Jaguar Experience, E-Type forum: Engine and Cylinder head color — Owners of 1967 Series 1 cars disagree over whether their heads should carry any colour at all, one reporting a head gold part way up and bare above, another reporting no colour anywhere, and a third stating that colour ended in 1966
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
The year is disputed. Three sources point at 1967: a JCNA judging guide records the last confirmed gold head and the first confirmed bare one within late 1967, a researcher on Jag-lovers says painting stopped during 1967, and the S-type Register cites 1967 Model Progress Meeting minutes recording that heads were no longer to be coloured. Wikipedia puts it at around 1968, with the arrival of the ribbed cam covers. The difference matters for anyone with a 1967 or 1968 car, and the JCNA engine numbers are the most useful handle on it because they bracket the change without needing a date. There is also a reported survival: a 1968 3.4 S-type with a bare head carrying a duck egg green identification dab at the rear, which suggests the colour survived as a marking after it stopped being a finish.
Sources for the bare head are strongest at the start of the range: the two judging guides cover the 240, 340 and Series 2 E-type only, and the extension across XJ6 Series 1 to 3 rests on Wikipedia saying later heads remained unpainted. Model years are each model's own production span from Wikipedia. Calling the finish silver, as many suppliers do, invites painting it silver, which is not the same thing at all.
club:The International Jaguar S-type Register forum: 3.4 head colours — A register member cites minutes of a 1967 Model Progress Meeting, quoted in Jeff Daniels' Jaguar the engineering story, recording that cylinder heads were no longer to be coloured; another member reports a 1968 3.4 S-type with a bare head carrying only a duck egg green identification dab at the rear
community:Wikipedia, Jaguar XK engine — Puts the end of head painting at around the time of the later Series 1 E-types and the 420G in 1968, alongside the arrival of ribbed cam covers, and notes that the bare finish is still often described as silver
Nothing was painted here: the covers are bare polished castings. The most useful line in any of the sources is the JCNA caution that a mirror finish is wrong: Jaguar's own polishing left casting marks, and a cover polished to jewellery standard is over-restored rather than correct. No source found says whether the covers were lacquered from new; owners on Jag-lovers use modern high-temperature clear coats to hold the shine, which is a preservation choice and not an originality claim. The end year is the earliest date any source gives for the ribbed covers, which arrived on the Series 1.5 E-type; see the ribbed cam cover record for the dispute over exactly when.
Sources
judging-standard:JCNA, Series 1 E-type Judge's Guide, Cam Covers and Polished Parts — Gives the Series 1 cam covers as polished aluminium with chrome dome nuts and copper washers, and warns judges that custom polished parts are of a far higher quality than anything Jaguar produced, so casting imperfections and the absence of a mirror finish are not to be marked down; the same caution covers the front of the cylinder head, the top of the 4.2 inlet manifold, the 3.8 water manifold and balance pipe, the thermostat housing, the breather housing and the carburettor dashpots
judging-standard:JCNA, Mark 2 Judging Guide (2009), Cam Covers — Gives polished aluminium held by chrome-plated dome nuts and copper washers for the Mark 2, and ribbed aluminium on a black background for the 240 and 340
community:Wikipedia, Jaguar XK engine — Describes the twin cam covers as polished alloy until a change to a ribbed black and alloy finish in early 1968
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
XK 2.8, 3.4 and 4.2 · 1967–1992 · cam-cover, gloss
Awaiting measurementB · Club verifiedDisputedLast verified 2026-09-20
Awaiting measurement
Not yet measured. The patch will appear once a spectrophotometer reading is recorded.
What is disputed
Two things are unsettled. The date: Wikipedia's XK engine entry says early 1968, but its own E-Type entry puts ribbed covers on the Series 1.5, which it dates from 1967, and the JCNA Mark 2 guide gives ribbed covers to the 240 and 340, which went on sale in 1967. On the fetched evidence 1967 is the earlier defensible date and 1968 is when it became general. Second, whether the black was clear-coated from new: XJ6 owners on Jag-lovers disagree, one holding that no cover ever left the factory clear-coated and that the gloss people remember is the decal laminate. Neither question is answered by a factory document here.
The ribs are bare machined and brushed alloy, not painted silver, and the black is only the background between them. Masking the ribs and spraying the rest is the whole job. Finish recorded as gloss because no source states a sheen for the black. Coverage across the XJ6 Series 1 to 3 rests on owner reports and on the covers being the same castings; no judging guide covering the XJ6 was found.
Sources
judging-standard:JCNA, Series 2 E-Type Judges' Guide, Cam Covers — Gives black with brushed aluminium ribbing, chrome elongated acorn nuts and copper washers, and dates the Series 2 variations from parts numbers and change dates of 31 October 1968 and 11 November 1969
judging-standard:JCNA, Mark 2 Judging Guide (2009), Cam Covers — Gives ribbed aluminium on a black background for the 240 and 340, secured by chrome dome nuts and copper washers, against polished aluminium for the earlier Mark 2
community:Wikipedia, Jaguar E-Type — Says the Series 1.5 had ribbed cam covers painted black except for the top brushed aluminium ribbing, and that the change from smooth polished covers to ribbed ones is the quickest visual identifier of a Series 2 engine
community:Wikipedia, Jaguar XK engine — Dates the change from polished alloy to the ribbed black and alloy finish to early 1968
forum:Jag-lovers Forums, XJ: Cam Cover Paint — XJ6 owners repainting covers disagree over whether the factory finish carried a clear coat over the black, one saying he has never seen a clear-coated cover and that what looks like one is the laminate of the decal, another believing there was one; they use high-temperature black spray enamel and sand the rib tops back to a shine
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
One source only, and it covers the Mark 2 family alone. It is recorded because it is the boundary a restorer gets wrong: the block is black, the cover bolted to the front of it is bare alloy, and a black timing cover is a repaint. Nothing was found stating whether the same held on the E-type or the XJ6, and it has not been assumed.
Sources
judging-standard:JCNA, Mark 2 Judging Guide (2009), Engine Block — States that the timing chain cover is natural aluminium while the water pump is black to match the engine, and that the block core plugs are cadmium plated and then painted black
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
Neither guide states a shade for the enamel, and none has been guessed; the record is here because the finish itself is the fact. A vitreous-enamelled manifold is a fired glass coating, not paint, and cannot be reproduced with an aerosol. Restorers who strip a chipped original and spray it silver or black have destroyed the correct finish, and no high-temperature paint will imitate it. Late Series 2 cars are the exception and are supposed to have bare cast iron behind a stainless shroud. Finish recorded as gloss because no source states one.
judging-standard:JCNA, Series 2 E-Type Judges' Guide, Exhaust System — Gives porcelain manifolds with brass nuts for the first two Series 2 emissions variations, notes that the English term is vitreous enamel, and records the third variation as bare cast iron under a polished stainless steel shroud, with some early cars of that variation believed original still carrying porcelain manifolds
History
2026-09-05 · Draft researched from public sources; unverified
2026-09-20 · Judging guide claims checked against the guides' own text; published
Most of an XK engine was never painted, and that is the first thing to get straight. The iron block was black. Everything above it was aluminium, and Jaguar's treatment of aluminium ranged from bare as-cast through buffed to a coloured enamel that marked which engine you were looking at.
The block is the settled part. Three JCNA judging guides, for the Series 1 E-type, the Series 2 E-type and the Mark 2, each give the block colour in one word: black. Only the XK120 guide commits to a sheen, listing the block among the components finished semi-gloss black whatever the body colour, because polishing lacquer took too long to extend it to them. That list sits under the heading for the nitrocellulose-painted Foleshill cars up to late 1952, so the semi-gloss reading is documented for the early cars and nothing more. The later block records are entered as gloss because that is this site's default when no source states a sheen. No source says gloss.
The head is where Jaguar used colour as a production marker. B-type heads on 2.4 and 3.4 litre engines were a pale green that the sources also call duck egg blue and duck egg green; 3.8 litre engines got a metallic blue. The straight-port head on the XK150S was orange, and the same family of colour on early Series 1 E-types is recorded as gold. The C-type head fitted to the XK140 SE and MC was red. The earliest heads of all, on the XK120 and the standard XK140, were not painted: the XK120 judging guide says they stay in their natural as-cast aluminium colour and are never painted.
Cam covers were bare polished castings. The Series 1 E-type and Mark 2 guides both give polished aluminium with chrome dome nuts and copper washers, and the Mark 2 guide adds that the timing chain cover is natural aluminium while the water pump is black to match the engine. On the E-type the exhaust manifolds were vitreous enamel, which the American JCNA guides call porcelain, with brass nuts.
What changed, and when
Two changes happened close enough together to be confused with each other, and both fall around 1967.
Head painting stopped. The JCNA Series 1 guide records gold through late 1967 and then natural aluminium, and brackets the change with engine numbers rather than a date: the highest confirmed gold head is 7E10192-9 and the lowest confirmed bare one 7E11938-9. The S-type Register cites minutes of a 1967 Model Progress Meeting recording that heads were no longer to be coloured. Both the Mark 2 guide, for the 240 and 340, and the Series 2 E-type guide give natural aluminium.
Cam covers went from polished to ribbed. The Series 2 guide describes them as black with brushed aluminium ribbing, chrome elongated acorn nuts and copper washers; the Mark 2 guide gives ribbed aluminium on a black background for the 240 and 340. That is the finish the XJ6 carried through Series 1, 2 and 3 to the end of XK production in 1992.
Earlier, the gold itself changed formulation. Per the 'E' Type Forum's administrator, Bradite supplied Jaguar a flat gold and then, from late 1961, a metallic version known as Old Gold under the same factory name.
Common mistakes
Painting something that was never painted. Bare as-cast heads, bare polished cam covers and the bare timing cover on a Mark 2 are all finishes in their own right, and all three get sprayed by people working from a photograph of somebody else's rebuild.
Over-polishing. The JCNA Series 1 guide tells judges explicitly not to deduct for casting imperfections or the lack of a mirror finish, because custom polished parts are of a much higher quality than anything Jaguar produced. A cam cover polished to jewellery standard is over-restored, not correct.
Painting the ribs. On a ribbed cover only the background is black; the rib tops are bare brushed alloy.
Spraying an enamelled manifold. Vitreous enamel is fired glass. No aerosol reproduces it, and stripping a chipped original to paint it silver throws away the finish.
Calling bare aluminium "silver". Suppliers do, and the next step is somebody buying silver paint.
What to buy
Less than you might expect, because most of this engine was never painted.
The block is black, and black has no shade to match. The early XK120 is the one case with a documented sheen, semi-gloss, and a satin black engine enamel is the nearest thing sold. For later engines no guide states a sheen, so gloss and satin are both defensible. The matches on the block records above are engine enamels rated well above block temperature.
Ribbed cam covers take the same black. Mask the rib tops, spray the background, and lift the tape while the paint is still soft so the edge stays crisp. The job depends on the masking far more than on the paint.
For the pale green 3.4 head there is one tin on general sale whose name carries both of the names the sources use: light green and duck egg blue. Its maker doesn't tie it to Jaguar and nobody has measured it against an original head. It is a sensible place to start and proves nothing. Spray a test card and compare it with any trace of original colour in the plug valley before you commit a head to it.
For the metallic blue, pumpkin and gold heads, we list nothing. The sources don't agree on the shade, no paint standard has been tied to any of them, and naming a tin would be a guess presented as a recommendation. Marque specialists sell paints for these heads, and the Jaguar clubs can tell you which ones their judges accept.
Buy nothing for a bare head, a polished cam cover, a Mark 2 timing cover or an enamelled manifold. Clean them, and leave them as Jaguar did. A chipped vitreous enamel manifold can be enamelled again by a specialist, and no paint will pass for it.
The date head painting stopped. Three sources point at 1967; Wikipedia's XK engine entry says around 1968, alongside the ribbed cam covers. Owners of 1967 Series 1 E-types report both gold heads and bare ones, and one states flatly that colour ended in 1966.
Whether pumpkin and gold are two colours or one. The 'E' Type Forum's administrator says Jaguar's records call the colour Gold throughout XK150S and 3.8 production and that pumpkin is a later American label for the flat version of it. The JCNA Series 1 guide treats them as two, with the change fixed by engine number.
What the pale head colour actually was. A judging guide and a register say light green; Wikipedia says duck egg blue on early cars and light green on later ones, which would make it a change rather than a naming difference. A service bulletin of November 1959 is cited on Jag-lovers as saying light blue, but that document was not read here.
The shade of the 3.8 blue, which is variously mid blue, dark blue and metallic dark blue. And whether ribbed covers were clear-coated from new: XJ6 owners disagree, with one holding that the gloss people remember is the decal laminate.
Finding original paint on your own engine
Work where heat and degreaser could not reach. The underside of the head's manifold face, the metal beneath a lifting bracket, the shielded flank of a boss and the area under a cam cover nut washer all keep colour long after the visible surfaces have gone.
On a head, check how far up the paint runs before you copy it. Originals are found painted only to the machined surfaces and others painted right through the valley, and that variation is itself unresolved.
The engine number is worth more than the paint. The JCNA guides bracket the end of head colour by engine number, so on a Series 1 E-type the number above the oil filter housing tells you more about what your head should be than any photograph will.
If you find something these sources do not predict, particularly a coloured head on a late 1967 or 1968 car, that is worth reporting. Tell us about it. This page rests on judging guides, a register's records and owners' testimony, and we have checked the guides' wording against the guides themselves. One measured reading from an unfaded original would still outrank all of it.
Every record above has a correction link. Applied corrections are logged on the record and on the changelog with their source and date.