Hi Guys

Does anyone know the name and make of the original 'under body coating'

used by Jaguar during production of the XJS.

Is it still available and if so what is it called and where can I get some.

If it's no longer available, what is the next best thing?

As I have heard that some sealants tend to trap water rather than prevent it.

 

its not something the company or anyone else really cared about, so there is probably very little information on it. Usually in restorations the most important part is just matching the grain/consistency of the original stuff. It is easy to think of undercoating as part of the paintwork, but the factory thought of it more like what kind of grease to pack the bearings with. That is actually better documented, because the owners manual will tell you what oils or greases the company was using at the time.

To make it original I would pay very close attention to where it was applied and where there are mask lines or overspray.
From what I can recall under my car, they painted the whole thing and then taped it off at a certain point and undercoated it.

The issue with sealants trapping water is 100% the fault of prep work. You need to get it extremely clean or get it all off so not pockets are trapped in it. If you are looking to re-undercoat your jag or are just doing some fender wells or something, I would go POR-15 all day long. Maybe eastwood if you need something cheaper


maybe someone will stop in with some weird factoids and knowledge about what coatings were used in production

 

OB
No undercoating at all was put onto the cars by the factory, at least not on the pre-facelift cars. Quite a number of owners had their cars treated by aftermarket firms such as Ziebart.

I firmly believe that the salt on the UK roads is the XJS killer. Not using them in salty conditions is one way to protect them. Coatings do help, but they cannot prevent salt doing its stuff, as there are so many water traps on an XJS, from the roof gutters downwards, that salty water will get to the metal somewhere. I waxed my car for years before the rebuild, and I used it all the year as a driver, and I do not think the waxing did much good as the only places it protected were the places I could get to, and all the other places went home.

I went to great lengths to protect my car when I rebuilt it, but even so, I try never to use it in the wet and never in the salty season. If you do embark on some serious protection, layers of different coatings are the thing, and you have to remove all the interior trim, drill holes in the sills, remove the front wings and windscreen trim, and send probes up into the flying buttresses and the inside of the rear wheelarches, and the structure above the sill to the side of the rear compartment, and below the rear seat metalwork, the headlights, rear lights, boot trim to so the inside of the tunnels, chassis rails, boot and bonnet crimped seams, etc etc etc.

If you do all this, and use aquasteel first, then special zinc chromate-type paint (nasty stuff, expesnive, but very effective) then wax over the top of all this (I favour Bilt Hamber stuff) I believe you will get very effective protection. The floors need a POR 15/Rust bullet type coating, as damp carpets are unavoidable and it is these that gradually humidify the sound deadening and then rot out the floor. But still and all, the XJS body will find a way to rust if it possibly can...

It may seem a great deal of effort, but there is nothing more heartbreaking than a perfectly functioning XJS rusting away round you. Never again!
Greg

 

after my XJS restoration a injected a product called wax-oil, 19-20 yrs and stiil is soft to the touch, sprayed into all the places Greg mentions, and any place that is open to moisture.
it seems to me that it was a mixture of parrafin wax and diesel fuel, the diesel wicks it into tight joints, then evaporates, leaving wax as a cover permenatly, also flexible coating.

my car(before me), came from Kent UK, i have talked with some mechcanics from UK they say that in early yrs for street ice removal, counties would mix powder pool acid in with the road salts, for more rapid ice removal, along with getting rid of old cars quicker!

probably just a rumor.

 

My 1994 sales brochure says "Bitumen wax underseal", "Box sections and closed members hot wax injected".....as per previous mention WAX-Oil (may have been spelled Wax-Oyl...maybe) was the only way to stop our british motors rusting overnight in the '60s and '70s....God how we used to dread the MOT testing !!!.

Rob.
2006 X Type Sport Wagon.
1987 XJ6 Daily driver.
1994 XJS 6.0 V12 Convertible.

 

Hi Greg

That Por15 looks the business! but I've never heard of the Stuff before and also it seems less expensive than some hammer paints.

But their range is so vast I'm not quite sure what combination of their products I should use.

I never use the Car in the rain or even in damp conditions and at the end of September, She's staying in the Garage for the Winter.

BTW. To day I splashed out and treated myself to one of those laser pointer temperature guns.

As I wanted to check the output of my Homemade Woodburning Stove, as last year it got so hot I nearly burned the house down.

But I also want to do some Engine Temperature Checks on the Jag, as to how hot the engine gets when its running and how hot it gets when you Switch it off.

Together with what happens, when you Switch it off and lift the bonnet/hood, as per your suggestion.

So if you would like to let me know of any particular areas under the bonnet/hood that you would like me to check please let me know.

I am also enclosing the link which may be of interest to others.

http://www.frost.co.uk/automotive-pa...15-paints.html

 

Hi Rob

Tell me about it!

MOT's are always something of a nightmare as there seems a lack of Consistency among some MOT Testers.

As you may have read in one of my Posts, the Garage that I have always taken my XJS to, appears to have never checked upon the Shock Absorber Bushes, in all the time I have been taking her there.

Resulting in so many Rattles and Bangs, I thought She was falling to pieces.

As a matter of interest, I have also used Waxoil and still use it to this very day but have always been curious, about the hard coating that Jaguar seem to use underneath their Cars.

 

you probably haven't heard of it because you are overseas. It is used on literally everything over here. Cars sell for hundreds of thousands after being restored with POR15 chassis paint and undercoating. It is THE brand.


greg are you sure about the pre-face lift thing? I have literally never seen an XJS without undercoating and its nowhere on any of my original dealer billing

 

Eastwood - Auto Body Repair Tools | MIG Welder | TIG Welder | Plasma Cutter | Auto Body Supplies & Accessories has a variety of rustproffing or undercoatings avaialble in spray cans, one is very much like wax-oyl. I have used it on a few of my cars, it is very good for spraying in enclosed areas, like inside rocker panels. Not so good for areas exposed to weather.
see Heavy-Duty Anti-Rust in Amber - Rust Proofing Products - Eastwood
BTW, I was not paid for this endorsement. But I would not turn down anything Eastwood wants to send my way. ;-)

 

On UK sold pre facelift cars built up to 1990, I am sure. it is quite possible that Jaguar realised in the 1980s that some coatings were needed for overseas cars, though. Even the facelifts, regardless of their zinc coatings and other things, rust away terribly in the UK climate.

Greg

 

I have an '89 UK spec XJR-s imported here by an immigrant and there's plenty of underbody coating in all the usual places.

 

Can't help you with the original but you have or should have accsess to a european product called U-POL, they have their version of pick-up truck bed liner that is tintable with the original color that should work as good as any por-15 product and should be more readily available to you across the pond. As mentioned it comes tintable or in black.

When I get back on the XJ-SC my intentions are to use the tintable version on the underneath and inside the wheelhousings after completely stripping and repairing any rust if needed.

 

be sure to check that stuff out to see if you agree with the texture. Bedliner and undercoating are two very different things. A lot of them come out looking like a sand paper coating and some of them are really glossy.

In term of not caring about originality though, matching it to your paint in your wheel wells can look really nice.

 

On my Red XJS The Original Under body Coating, did have a finish like Sand Paper which I wanted to replicate as it was a very hard finish and looked good.

Any idea what that was?

 

My DD is a Mercedes and when I was talking to this Guy who was a bit of an expert on Mercs, he actually mentioned using 'Pick up Truck Bed Liner!'

 

Hi Greg

On my 2 X 1990's and 1 X 1989 XJS's The Original Under body Coating had a rough finish like Sand Paper.

Which has proved very durable over the years, so I am very curious as to what this stuff was.

 

Hi Doug

Not seen Eastwood Products, in my local Motor Factors.

As for Internal Rustproofing, it seems to be Ziebart or Wax Oyl in the UK

 

Not seen any POR 15 in my local Motor Factors in the (UK) but now I am going to ask around, as it does seem to have an awesome reputation as a great product.

 

I will definitely look into POR 15 it sounds like a really great product.

 

OB rustoleum has a product like POR-15, my local paint supplier says its is identical, along with price!

i used some on another car directly on some rust, and been around 5yrs and still looks good ,rust has not spread any further.

of course cutting out the rust and inserting new sheet metal, welded, is the prefered method, but to each his own, a complete restoration or an acceptble restoration!

and yes Eastwood USA are top suppliers of almost any body,paint and tool suppliers.