Just cleaning these up as I strip the engine.
Can anyone tell me what colour the pipe and unions should be on a '55 140DHC, SE engine with C-type head?
Every part of this engine has black oil crust baked onto it which is a swine to clean off. However on the pipes and union I’m wondering if this is actually a typical 50s/60s ‘coat’ of black paint. You know the one, no prep, no primer, just a quick shoot of gloss black over the bare (probably oily) metal. It’s a bit uniform for staining, and some of it is very stubborn.
Viart doesn’t give any colour info for this assembly, although the union elements are coloured brass and the pipe silver (bare metal?) in the drawings.
Anybody know?
Hi Roger:
Not sure about the XK140, but the 120 oil feed lines are silver (bare metal) with the unions brass, I suspect that yours will be the same although I am sure 140 owners will weigh in.
Chris.
Unpainted steel pipes, unfinished brass banjo unions but with silver solder visible at the joints, unpainted steel banjo bolts.
Thanks very much, chaps!
In XK140 EXPLORED my efforts at detailing all finishes was belated, but in places I did get Viart to start shading colours to represent finishes, but still ran out of time with publishing deadlines to do too many labels/descriptions of finishes.
The subject Camshaft Oil Feed pipe - on an XK140 - was made of two lengths of ‘Bundy Tube’ (Google it) which has a protective alloy steel composition, and is left untreated in its natural ‘silver’ appearance, and will not rust unless subject to unusually extreme/long term exposure. Any slight rusting can be simply wet & dry polished off back to its natural silver-steel finish.
The three fittings are cast brass, and left in their natural ‘as-cast’ finish, and not polished. The internals and faces are simply machined out. The two natural finish bundy tubes are fitted into the three natural finish cast brass fittings, and silver soldered in place, thus a bright silver flash at the bundy-tube/brass fitting joints.
That’s it. No subsequent plating nor painting - its all ‘au naturale’ as per our colouring/shading efforts in XK140 EXPLORED.
With an XK140 at least, the three steel Banjo Bolts are indeed Cadmium Plated, albeit I think the transition from blackened bolts to Cadmium Plating happened in about 1952/3 XK120. I don’t know supplier of these Oil Feed pipe Banjo Bolts, but the SU supplied Banjo bolts as used on fuel delivery pipes were initially Walterised (a chemical process that gives a black-oxide finish), and then from about 1952/3 Cadmium Plated.
(Maybe same timing for the Oil Feed pipe banjos - but that’s a guess as I haven’t investigated specifically)
Roger
I would have said the banjo bolts on camshaft oil lines on the XK120 and therefore 140 were nickoll or chrome plated?
Maybe instances of Dull Nickel/Chrome during XK120 period Terry, as before I haven’t specifically looked at non SU banjo bolts as used on oil feed pipes.
But I have with XK140 - and stand by my steel banjo bolts being cadmium plated (and not zinc), and the nature of aged/exposed cadmium can make them appear to be unplated.
I suspect the cadmium plated transition would have happened sometime late XK120s, but before the first XK140s.
Dull Nickel and Dull Chrome plating was more usually applied to brass fittings.
Walterising and Cadmium Plating more usually applied to steel fittings, but that’s a general comment as there can be exceptions re plating.
Owners of original/unrestored XK120 owners may wish to comment - with emphasis on unrestored.
Roger
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Thanks Roger - my 140 has never been restored until now, and apart from the C-type head having the valley painted gold over the faded red I would say the finishes are all original. The three brass banjo castings are indeed silver cadmium plate (not yellow) and in surprisingly good condition, probably due to the baked-on oil coating. I’ll be leaving them as is, because cad plating is not permitted in the UK anymore and how they are now is better than going to bright zinc plate.
My engine(G5752-8S) has brass, unplated banjo fittings, as Roger described. But I am surprised to here that the tubing is CuNiFer…though I don’t remember much, if any, rust on my tubes…certainly would explain the lack of rust.
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Lee, I don’t profess to be a materials expert, but have a working knowledge, but still should have been a little more careful in my comments.
By saying ‘Bundy Tube’ I meant the original high-pressure mild-steel tubing that was alloyed with Zinc and I dare say other things that gave it its high-pressure suitability better than basic mild-steel. The side benefit of the alloying was a significant degree of corrosion resistance, but not rust-proof. This was the initial special purpose material used for brake lines, fuel lines and I believe oil-pressure lines, and it has a dull-silver-grey appearance with no hint of yellow/copper etc.
Cunifer tubing was I understand a later development of better anti-corrosion properties, especially for use in countries in the habit of salting roads where bundy-tubing brake lines could rust and eventually fail. 100% unheard of in Australia, but I understand a significant problem in UK. So in UK (and I dare say other snow/salt environments) Cunifer tubing replaced bundy tubing for brake line applications, albeit in some respects it has inferior pressure characteristics. The Cunifer tubing I have seen has a distinctly yellow/copper apperance, so nothing like original 1950s Bundy tubing.
Problem these days is most of the specialist suppliers, only offer new brake lines in Cunifer, even if you ask for Bundy (the two names have merged in supplier/sales/user speak).
When I remade all my XK140 brake lines, the originals remained in perfect non-damaged/non corroded condition, but were all LHD. So remaking a RHD set, I was able to source sufficient correct/original Bundy tubing to do so, and now have brake lines indistinguishable from 1955 RHD originals (including all fittings). I did flirt with a stainless-steel offering from USA, but they only offered/made for LHD, and work-hardens if you try to rebend, and fittings were not 100%.
With oil-feed pipes, rust is not a problem - even when roads are salted.
Same with fuel lines, so I acquired three different diameter Bundy tubing.
Cad Plating is theoretically also now banned in Australia for safety and environmental reasons, but given it does look quite different to Zinc plating I was motivated. But as it is BETTER than Zinc Plating, in Australia there is an exemption for both the Defence and Aviation Industries, but still strict environmental controls/licensing, thus a couple places in Melbourne and Sydney can accommodate (through the back door) limited automotive parts, they want to charge chrome plating prices for the privilege.
But fortunately for us, in WA and SA (and probably NT) there is an ongoing demand from the mining industry, thus a number of facilities that still will do Cadmium Plating (legally) at sensible main-stream prices, just a postage charge extra given not really a drop-in distance. So with my XK140 everything that was originally Cad plated is getting/has been replated in cad, and not a hint of zinc to be found anywhere. Suits me, albeit I doubt to many others would notice, nor indeed care.
You can still get Cad Plating done in USA - before locating the WA/SA sources here, I was on the verge of posting parcels of parts to USA to be plated.
Where there is a will ………………….
Roger
I certainly merged the words, thinking they DID describe the same material…my goof.
Here’s a bit of information about Bundy and Kunifer tubing.
Kunifer (also spelled cunifer or sold as cupro-nickel) is gradually replacing Bundy for brake lines. I have done all my Mark V brake lines of cunifer.
On my '51 XK120 the banjo bolt heads are plain steel, no plating, so one could presume that this practice of plating began some time after that.
Another data point;
G7938-8 has unplated brass banjos, but I can’t determine if the corresponding bolts have any plating or not. I think it is time I cleaned off the engine…
Speaking of fasteners, take a look at what a previous owner did to a camcover stud on this engine…looks like they carelessly hacksawed right through the stud, slicing into the camcover itself…
Oddly, the remains of the cut off stud unscrewed easily from the head when I replaced it with a new stud !
Looks like you’ve got the C type cam covers on there…blasphemy!
Hey Lee, you caught me big time…but my lousy excuse is that I do have the actual engine (G8931-8S) these C Type cam covers came off, but that engine is damaged and not running.
At least I haven’t painted the G7938 cylinder head valley red (…yet) tee hee
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