Engine block corrosion?

[AJB2]

If it helps at all, I’ve owned a Land Rover Discovery from new for 21 years. Parts of the engine, bell housing & other alloy components have been like this for as long as I can remember. 178,000 miles later & it’s never been an issue.

[RPSN]

Thanks, that’s reassuring to hear.

Still, you shouldn’t see this amount of corrosion inside the engine bay of a car such as the F-Type.....(see pics of mine).

Have you ever used ACF-50 or anything else to help protect these alloy components?

[TopCat]

Yes, it is very reassuring.

Most of the parts affected are difficult to access and probably there are more areas that are not visible with similar amounts of corrosion / oxidation on them.

I think if I was to spray the parts I’d use Bilt Hammer Atom Mac which I use on the brake disc.

https://www.bilthamber.com/corrosion-pr ... s/atom-mac

[Quiet man]

Personally it wouldn't worry me every car I've owned has had this kind of oxidation on it to some degree, I've never heard of a engine block failing through this kind of corrosion, I appreciate that you spend a lot of your hard earned cash on a car such as this but as its exposed to the elements its unavoidable I am afraid. I road motorcycles for many years and the first thing I would do on getting home would be to clean the bike down, much easier to do on a bike as most of the engine was exposed.

[RPSN]

I haven’t used any of the Bilt Hamber products e.g Atom Mac but I’ve seen plenty of good reviews on them.

Something to consider is the wiring etc in the F-Type engine bay (around the areas that we are concerned with)......I don’t think it’s going to be too fond of having even more liquid sprayed/splashed all over it a couple of times annually?

All the years I had motorbikes (none undercover), they didn’t have as much corrosion on the alloy engine components as this.

Just had a look in the engine compartment of my 19 year old BMW and the alloy parts are also faring better than the F.

Don’t get me wrong, I love my car but it could really do with some higher quality on components such as this.

I intend to keep the F for many years as I have done with most of my cars but as it’s only 5 years old the corrosion on the rear of the engine block and bell housing does concern me.

If you zoom in on this photo where I’ve marked it with arrows, in my opinion that sort of corrosion is going to do some serious damage after a number of years.....it’s turning things to dust!

Time to get some sort of protection going on me thinks!

[GBH]

https://www.allmetalsfab.com/does-aluminum-rust/ I wouldn't worry about it, all cars do it.


The terms rust and corrosion are often used interchangeably, but they’re not the same. Corrosion is a broad reference to the wearing away of metal caused by a chemical reaction. Rust is a type of corrosion referring specifically to the oxidation of iron or steel caused by interaction with water or moisture. So does aluminum corrode, or does aluminum rust?

Aluminum doesn’t contain iron or steel so it doesn’t rust – but it is prone to corrosion when exposed to weathering and atmospheric oxygen. The process of aluminum corrosion is known as oxidation. The resulting aluminum oxide is a thin, hard layer that actually protects the metal from further corrosion.

Aluminum oxide appears as a powdery white or dull gray coating. As oxidation occurs, it hardens and creates a protective layer over the newly exposed areas of corroded aluminum. The aluminum corrosion process is actually halted by oxidation – the metal won’t continue to deteriorate unless the aluminum oxide is removed. Unlike rust, which has a flaky, reddish appearance, aluminum oxidation cannot be easily chipped off the metal surface.

Aluminum oxidation occurs at different rates depending on the type of aluminum, the finish, and the environment surrounding the aluminum. Aluminum 5052, for example, is sometimes called The Hulk of aluminum alloys due to its durability and excellent corrosion resistance. Aluminum 3003, the most widely used of aluminum alloys, is also particularly good at resisting corrosion, but less favorable to anodizing, a factory process that mimics the natural process of oxidation to create a more durable metal with a corrosion-resistant aluminum finish.

[Tel]

The particular OP looks to be a combo of oxidisation and possibly some coolant attack. The reason I say coolant, is the depth of scour in the metals' surface.

The only way to stop ally oxidising is by sealing it on day one. By seal, I don't mean your fancy automotive sprays, you require something that 'films' and provides an effective seal against oxygen.
For coolant, then you need to find the source of the leak.

For the past 30 odd years I have been experimenting on many bikes and cars.

I have recommended marine sprays such as Quicksilver Corrosion guard within many posts on this forum.
JLR use Würth products on the replacement underbody braces to seal the already coated steel surfaces.
You need that understand that automotive products are pretty lame at what they claim. Marine and aerospace though you not only go up in price, but you get a product that actually does what it is supposed to do, effectively.

I was fortunate, having bought the car brand spankers, on the journey from the dealer to home, I stopped at my local friendly garage and spent a couple of hours sealing everything, top and bottom. Subsequently it's like the day it left the showroom. The same can be said for my bikes, of which he oldest is 30 plus years and the ally work is as new.

Several ways to clean it up - You need acid. I would suggest Alubrite (https://www.chemwash.co.za/DataSheets/alubrite.html)
It works perfectly, and you need to be cautious of surrounding materials, so be handy with the hose to neutralise.

Once clean, start the engine to dry and 'seal' - Alternatively you could just leave it, but it doesn't look particularly pleasing to the eye.

[RPSN]

https://www.allmetalsfab.com/does-aluminum-rust/ I wouldn't worry about it, all cars do it.


The terms rust and corrosion are often used interchangeably, but they’re not the same. Corrosion is a broad reference to the wearing away of metal caused by a chemical reaction. Rust is a type of corrosion referring specifically to the oxidation of iron or steel caused by interaction with water or moisture. So does aluminum corrode, or does aluminum rust?

Aluminum doesn’t contain iron or steel so it doesn’t rust – but it is prone to corrosion when exposed to weathering and atmospheric oxygen. The process of aluminum corrosion is known as oxidation. The resulting aluminum oxide is a thin, hard layer that actually protects the metal from further corrosion.

Aluminum oxide appears as a powdery white or dull gray coating. As oxidation occurs, it hardens and creates a protective layer over the newly exposed areas of corroded aluminum. The aluminum corrosion process is actually halted by oxidation – the metal won’t continue to deteriorate unless the aluminum oxide is removed. Unlike rust, which has a flaky, reddish appearance, aluminum oxidation cannot be easily chipped off the metal surface.

Aluminum oxidation occurs at different rates depending on the type of aluminum, the finish, and the environment surrounding the aluminum. Aluminum 5052, for example, is sometimes called The Hulk of aluminum alloys due to its durability and excellent corrosion resistance. Aluminum 3003, the most widely used of aluminum alloys, is also particularly good at resisting corrosion, but less favorable to anodizing, a factory process that mimics the natural process of oxidation to create a more durable metal with a corrosion-resistant aluminum finish.

Thanks for this information.

Particularly.......”The resulting aluminum oxide is a thin, hard layer that actually protects the metal from further corrosion.”

and.....

“The aluminum corrosion process is actually halted by oxidation – the metal won’t continue to deteriorate unless the aluminum oxide is removed.”


I've also done some research on the subject of aluminium corrosion and found this from the UK Aluminium Federation (ALFED).....

“Although aluminium is a very reactive metal with a high affinity for oxygen, the metal is highly resistant to most environments and to a great variety of chemical agents. This resistance is due to the inert and protective character of the aluminium oxide film which forms on the metal surface. In most environments, the rate of corrosion of aluminium decreases rapidly with time. In only a few cases, e.g. caustic soda, does the corrosion rate approximate to the linear.”

“Although the oxide film is extremely thin, between 50 and 100 Angstroms, it forms a protective barrier between the metal and the surrounding medium as soon as the metal comes into contact with an oxidising environment, such as water. The physical-chemical stability of the oxide film determines the corrosion resistance of the aluminium. This stability is dependent upon the pH value of the environment, since the oxide film is stable within the pH range of about 4 to 8. Below and above these values, acid dissolution yields Al3+ ions and the alkaline dissolution leads to the formation of Al(OH)4 ions."

“Casting Alloys: Aluminium casting alloys are still commonly specified as the LM series from the former BS 1490. As the current standard is now BS EN 1676, with a five-figure designation, the information below refers to the LM series, but with a BS EN 1676 equivalent in brackets."

"Most aluminium casting alloys are classified as having good corrosion resistance, and if used for purposes involving exposure out-of-doors, they will suffer no appreciable loss of strength as a result of corrosion. Weathering tests lasting more than ten years, carried out by The Association of Light Alloy Refiners, confirm that there is little difference in the resistance to atmospheric attack of the casting alloys LM2 (EN 46100), LM4 (EN 45200), LM5 (EN 51300), LM6 (EN 44100), LM21 (EN 45000) and LM24 (EN 46500). Under normal weathering conditions, superficial attack and the surface appearance of the castings are more influenced by the particular atmospheric conditions of the exposure site than by the differences in composition between the alloys."

https://alfed.org.uk/files/Fact%20sheet ... rosion.pdf

I wonder if the aluminium that Jaguar UK uses for the engine block, bell housing and bodywork etc on our F-Types is produced in the UK or abroad?

[GARETH]

I don’t think Jaguar make/made the V6! It’s a Ford engine isn’t it? Not sure where they were made.

[RPSN]

Yes the AJ-V6 and AJ-V8 are Ford engines which were produced at the Ford Engine Plant in Bridgend, South Wales. The Plant closed in September 2020 and Ford ceased production of both those engines. However, in August 2020 JLR was able to take over production means for the AJ-V8.

I'm not sure if the aluminium used for the engine block was sourced in the UK or abroad?

Just done a search and I understand that ‘Hydro’ serves Jaguar Land Rover as a long-term partner and supplier of extruded aluminium solutions. This includes elements of the body structure, air suspension systems and exterior trim. It doesn't appear to include the engine block and bell housing though.

https://www.hydro.com/en/about-hydro/st ... aluminium/