Colour code for XK cylinder head

I noticed that cylinder head on XK engines are painted with various colors (Gold, Silver, light bleu). Is there a code for these colors ?

On the E-types I have only seen pumpkin color on some early cars, then gold on many cars up to sometime in 1967 I think and then bare metal. At one time I thought I heard that gold meant it was a 9:1 compression engine but that could very well be incorrect.

David
68 E-type FHC

There are certainly some errors in this document (eg, S1.5 E-Types all had unpainted aluminium cylinder heads as far as I know), but it is a starting point:

-David

As you say David … a starting point …, but sadly so full of errors throughout, an exceptionally misleading starting point, thus more trouble than its worth. After having first seen this ‘effort’, I never refer to it again…

But one very relevant aspect picked up is that of all the colours Jaguar ever painted Cylinder Heads in the 1950s and 1960s, NONE were ever PAINTED SILVER. This listing and others, mistake unpainted cylinder heads, left in their natural as-cast-aluminium colour, as being ‘painted’…

And it is also misleading to use the un-official term S1.5 or Series 1-1/2 as what that means in JCNA USA circles, is at odds with the terms use in UK and Australia, and I dare say everywhere else not part of JCNA. But yes, if you are referring to the cylinder head as fitted on USA market E-types (XKE :frowning: ) , that comply with the the local USA 1968MY Emissions Standards then yes, these heads were indeed left unpainted in their natural cast-aluminium colour. But the cylinder head as fitted to a UK or Australian Market 1967 E-type (that we refer to as S 1-1/2) still has its cylinder head painted GOLD.

But back to Bernard’s initial question - it would be useful to know whether it was just a general interest ‘across the board’ question, or whether for a specific model and year XK engine, and indeed what country he is in… For E-types its relatively simple, but for XKs and Saloons it gets a lot more complicated…

My impression of the “color codes” varies with the major restorers that I am familiar with. As for the gold painted heads, some restorers use a light gold paint while others use a more yellow gold. They tend to have their own mixes or favorite rattle can paint. USA bound E-Types built sometime in late June 1966 began having unpainted heads.

–Drew

Roger,

I understand your disdain for this effort, but can you recommend a better one? If not, is anyone motivated enough to generate a more accurate version?

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That’s interesting. It seems to be generally accepted (@DrewSchertz makes reference to it above) that Jaguar ceased painting the cylinder heads of cars destined for the US at some point in 1966, some time before there was any US-specific emission requirements. It would seem strange for the factory to paint heads differently for different markets if there was no other reason to differentiate them.

Corrections, please:

Off the top of my ‘head’ ( :slight_smile: pun intended) I recall Steve Kennedy (from Colorado) made up an accurate colour/pictured Chart of all cylinder head colours, and my recollection is that it was spot on after a few back and forward edits. But aspects certainly get complicated, especially when you get to shades of colours. For years I referred to XK150S and early E-type/Mark 10 heads as being painted PUMPKIN , until I was taken to task that in USA (Maybe some spots, not all???) a PUMPKIN was green inside, and not always the orange that I was familiar with, so I now say PUMPKIN ORANGE. But there is still debate what the factory official term means ‘Old Gold’ - is that this XK150S/early E-type PUMPKIN ORANGE or the 1962/3 onwards more metallic GOLD colour, but then in Steve’s chart he also identified an interim more yellow than gold colour - so three colours for XK150S and Series 1 E-type and 3.8/4.2 Mark 10/420 heads - the operative thing being all being ‘straight-port heads’ and not the various B-type heads painted other colours. So all straight port heads were painted initially PUMPKIN ORANGE, then YELLOW-GOLD (very briefly) then GOLD (lets say OLD GOLD) then left natural cast aluminium (NOT painted Silver) (so Series 2 E-type, 240/340/420 420G, XJ6 and some debate when back into 1966/67/68 Series 1 E-type and 240/340/420) with the debate being the exact demarcation. I will defer to local USA expertise when OLD GOLD stopped, and heads were left natural aluminium - I had always simplistically thought it aligned with the 1968MY twin-Stromberg emissions detuned engines (so from August 1967 on) but I am sure the local knowledge/advice is more likely correct.

I will have a look for Steve’s cylinder head colour chart, but if I can’t find it I will ask Steve, or those that know him can contact him direct…

And for completeness…
C-type heads as fitted to XK140MC only were painted RED. (Those fitted to C-types and after-market spare heads, or SB95A heads, retrofitted to anything, including XK120 were not painted at all - so natural aluminium, noting that only C-type heads made from early 1955 included the large cast ‘C’ to be readily identified as such). All A-type heads (XK120, XK140 not MC, Mark VII, 2.4 litre) were left natural aluminium. All B-type heads when fitted to a 3.4 litre block (XK150, Mark VIII, 3.4 litre and Mark 2 were painted what is often called DUCK-EGG GREEN, but over the years into the 1960s Mark 2/S-type application was more a DUCK-EGG BLUE colour. B-type heads when fitted to a 3.8 litre block (Mark IX, 3.8 XK150, 3.8 Mark 2, 3.8 S-type) were painted metallic MID-BLUE.
That pretty well covers it, albeit matching exact colour shades is a challenge, and some of the shade variations seems to evolve a little, so exact demarcation dates are not readily apparent.

If someone really wants to know - best to give exact model of car, engine/head fitted and date-of-manufacture, and that maximises chance of getting a more precise answer… General questions - get general answers…:slight_smile:

See attached .pdf…
This is Steve Kennedy’s efforts from some years ago - I think he had them printed off as a large size wall chart (so photos work well), so if anyone wants a copy, contact Steve direct if you know him, or me privately and I will give his contact details…
Typical Steve - a superb effort … :slight_smile:

021917 Cylinder Head Colours.pdf (265.8 KB)

A good guy: I gave @V12_Racer my limited edition of Steve’s Jaguar book.

Thank you Roger. More information than anyone has a right to expect, as always :smiley:

Thank you David.

When I know more I’ll let you know.

Besr regards

Bernard

Compression Ratio has zero effect on cylinder head colour.
But with B type heads whether with a 3.4 or a 3.8 block does effect pant colour applied to head. So the logic is not consistent as a straight port head is always Gold ( or Pumpkin Orange) depending on age, regardless of whether 3.4, 3.8 or 4.2 block.

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Hi,

Earliest known unpainted straight port cylinder heads on E-types were as early as July 1966. By next year, July 1967 all cylinder heads were unpainted, unless some old stock was being used in some models. Factory photographs support this.

The biggest error regarding this as a data source has been that colour photo in many books quoted being from 1968 or 1967 when it in fact was taken before noon on June 22nd 1966.

Cheers!

Ps. This one: http://www.xkedata.com/gallery/zoom/?id=185293

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The original cylinder head paint was produced by Bradite and Jaguar records show it was ‘Gold’ although as it was to BS381c standards it was known as ‘Golden Yellow’ in the paint industry. Those same records do not show a different colour paint used after 1961 - it is recorded as ‘Gold’ throughout XK150S and 3.8 production.

Confusion was caused by Bradite supplying Gold metallic (known as Bradite Old Gold) to Jaguar from mid 1961 onwards rather than the solid Golden Yellow used previously. We do not know whether this was a request from Jaguar after supplies of Golden Yellow were exhausted, a clerical error in the order process or production problems at Bradite which forced the change. The early cars non metallic paint has retrospectively been called ‘Pumpkin’ by the Americans who know what that vegetable is but a puzzlement to us Brits (we don’t have Pumpkins - Turnips, yes but also a different colour!).

Even today many paint manufacturers have a solid paint in their range that is called Gold (e.g. Crown has ‘Tivoli Gold’ trade paint which is very close to the fabled Pumpkin). If we go back to basics and consult the British Standard paint charts in use during the 1950’s/1960’s we find BS381c-356 ‘Golden Yellow’:

BS381-356 ‘Golden Yellow’ is the correct period colour for the cylinder head for the early cars. Hex value #F2A600. Bradite do produce a heat resistant paint called ‘Fastrac Heat Resist’ and it appears to be available in BS381c colours.

When I bought my USA spec Feb 1968 FHC from the original family in 2000 it had very old looking gold paint on the head even on that area on the side just above the exhaust manifold and below the cam cover. None of the receipts they gave me talk about any major engine work where the head would have been removed or replaced. I always have wondered if my head is from old stock or if the original owner did a very neat and thorough job of adding gold paint early in his ownership. It will probably always remain a mystery. If I ever do need to pull the head I will probably strip off all remains of the gold even though I do like the looks of the gold heads.

David
68 E-type FHC

I think I know where the poiple tribute to Tweety will go…!

Hi David,

Interesting data pojnt for sure.

So was “Feb 1968” the time when the cvar was first registered new in the US or the actual time the car was built in Coventry UK?

If that’s the time it was first sold and registered in the US I would not be surprised if it had been built between August and November 1967 in which case it could have had a cylinder head that was painted gold at the factory, in late 1966 it seems only automatic 2+2 had the non painted heads in the beginning, perhaps something to do with the way the engines were assembled at the engine plant and the delivered to the Browns Lane plant.

Was the engine number also stamped onto the front of the cylinder head? (#E14XXX-9 or 7E15XXX-9?) And matching the engine originally in that car? Do you have yours on www,xkedata.com or would you mind telling us the chassis number here? #1E34XXX?

Cheers!

Onto your head? :slight_smile:

Cheers!

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