What is rubber and how is it used on your classic?
We have all seen cars that have emerged from a long period of storage, some that are obviously in need of a total rebuild, but many others that are in visually brilliant condition but still usually need all ‘rubber’ components replaced before they can be brought back into safe regular use. Such a need after a thirty of similar year period in storage is to be expected as we are all aware that many components of our cars including rubbers degrade with time.
‘Rubber’ also includes synthetic rubber components such as EPDM (ethylene propylene diene monomer, if you wanted to know), and this degradation will in time for some parts lead to compromised safety; a sudden failure of an aged tyre or brake seal could be catastrophic, but equally a failure of a coolant hose could be damaging to your engine or a weather seal not keeping out rain is at the least very inconvenient.
When is rubber not rubber? Did you know, the traditional manufacturing process of extrusions, such as door and glazing seals uses shredded rags from the rag trade for infill? Too high a constituent will stiffen the seal and lessen pliability. MGOC Spares has been working with manufacturers to improve pliability with increased neoprene for longevity suitable for the job the component has to deal with.
Natural rubber is as the title says a natural product and as such will always want to degrade and even when blended with other materials to slow this natural tendency will only slow it. This natural degradation is accelerated by the presence of UV in sunlight, oxygen and ozone in the atmosphere, heat and even long-term exposure to water. There are also many synthetic types of rubber that are created to provide improved performance and life over a product created from natural rubber, but they still degrade over time from exposure to the same conditions.
A classic car will often have more exposed ‘rubber’ components than a modern car and of course, the materials used originally in the classic car were of the period when it was manufactured, and will often not be as durable as equivalent modern materials. There are some basic visual checks that can be done to any ‘rubber’ components to note if there is clear degradation and feel is a great means of assessment, such as squeezing coolant hoses and feeling them crunchy, or seeing a cracked surface, but age will always be the main guide.
Tyres
Tyres are the easiest rubber items to examine for ageing and for many years there wasn’t a great deal of focus on age affecting the tyres' performance, although it always did. Who remembers the 1950s widely circulating claims that the Michelin X tyres fitted to the Citroen 2CV would last the life of the car or the fact that carbon black was added to the mixture so the tyres would be black rather than white? Whilst tyres lasting the car's life was probably true how well they would grip the road when twenty, thirty or more years old is a mute question, but then 2CV performance was more focussed on the ability to drive across a ploughed field with a tray of eggs on the back seat and not break any!
Today there is a legally binding ten-year replacement rule for HGVs and buses for tyres on a steered axle but this hasn’t cascaded down to cars - yet, but it is noteworthy to report that now the general tyre industry accepted the life of a car tyre has dropped to five to six years as this is when the tyres best performance starts to wane. Note all tyres have a four-figure date code for the week and year of manufacture on one sidewall.
Replacement is economically impractical for most car owners and especially classic car owners whose cars do very few miles annually. Of course, it’s not as if the tyre grip falls off a cliff at that young age, although once the age passes ten years the question is more valid and how the car is used and stored has a considerable influence, with a low mileage car stored in a dark dry garage will see much longer tyre life.
Tyres can be aged faster by some stronger acidic or alkaline wheel cleaners so it’s beneficial to look at pH-neutral cleaners and also tyre dressings that offer restorative properties and additional UV and other surface protection. Interestingly many of the tyre dressings can also be applied to other rubber and plastic parts of the car and offer similar benefits.
Cars laid up for long periods can see benefits from Tyre Savers. These are plastic moulded blocks with a curved inner shape for tyres to sit on. Very long term this reduces the potential for tyres to develop flat spots, but a much more immediate benefit is to allow the car to be stored without the need for the handbrake to be on, so avoiding rusted on brakes.
Rubber Parts
There are many other rubber parts, especially on classic cars or more accurately those on classic cars tend to be more exposed and visible such as door seals, often designed to fill larger panel gaps.
These will have greater exposure to sun and weather that will accelerate degradation and here there does seem to be a situation where the replacements seem to have a shorter life before they start showing the same tell-tale signs of degrading, although many owners are surprised when they find original receipts for when they bought them and find that it was some years before they thought!
Rubber parts that are more hidden may not show the same urgency to degrade and an example that displays this well are the original rubber ‘top hat’ shaped front suspension inner wishbone bushes for the MGA and MGB. These are often failed at an MOT because the visible ‘top hat rim’ part of the rubber bush will often display the dry cracked surface that immediately attracts the examiner's eye, but almost every one when it is removed will only show that surface area of cracking and the rest of the bush inside will be as sound as when it was first fitted and importantly still doing the job intended.
Now looking at the degradation of the visible edges of the ‘top hat rim’, so what is causing the degradation? The question also applies to other rubber components such as steering rack boots, soft and hard top seals and door seals. One serious suspect has to be the huge rise in chemical car cleaning products that attract us to buy because they hint at making car cleaning easier, quicker and gives a better finish than traditional cleaning.
The local £10 car wash with many hands pouncing like hungry wolves as soon as your wheels stop turning may seem attractive, but hold on! Wheel cleaner is first onto the still hot wheels; definitely not good, then other products over the rest of the car to loosen dirt still with some other hot areas; also not good, followed by cleaning with hand mitts from buckets with a soapy mix; that includes dirt from the previous cars, before swilling off with a hose and finally spraying water dispersant to give a quick shine.
Immediate results look impressive and all done in an impressively short time seems good value, but what is in those cleaning products and what is it doing to rubber and plastic, and possibly to the painted surfaces to promote that super shine, which is perhaps not that long-lasting? Quite a lot probably and it appears that evidence is increasing that our modern approach is significantly shortening the life of many rubber and plastic parts of our cars, and indeed painted surfaces.
Those inner wishbone bushes give us a real clue as only the exposed ‘top hat’ edge degrades and the inner bush being completely protected from contact with only the steel of the lower arm remains fine. So could we apply a product that adds a protective layer on our rubber products to provide a little extra protection? The short answer is yes, but probably a more effective immediate change is to stop using the £10 car wash, and indeed some of the car cleaning products we buy, or at least until you have checked out what is actually in those products.
Do avoid clearly acidic or alkaline products and choose those with a neutral pH 7, such as Red Shift alloy wheel cleaner from MGOC Spares. You should also avoid any petroleum-based agents containing hydrocarbons that often have a greasy feel for the same reasons.
Choosing the right rubber? This is where sourcing from reputable and established suppliers is crucial, particularly for safety-critical components. MGOC Spares only uses E10, type approved
fuel hoses and SAE J20 specified cooling hoses for longevity and they continue to respond to the changing needs of classic cars in modern environments.
MGOC Spares goes to some lengths to source cleaning products from suppliers who have a proven track record in developing cleaning products that have been carefully developed to enhance without long-term degradation. I have a handful of other suggestions to briefly mention, but of course, having a chat with MGOC Spares directly about what is available for your car is well worth the time.
Starting with the very well-known and respected Autoglym products and their Vinyl and Rubber Care that has a neutral pH of 7, which provides cleaning and a degree of restoring the original finish to both types of material, depending of course on how bad the materials' condition is. This is predominately aimed at car interior materials and door seals, and why it has a lemon smell, but it is equally effective being applied in engine rubber and plastic parts and adds the same protective coating to extend the components' life. Nothing is stopping the keen owner also applying to other exposed rubber parts on or under the car such as steering rack boots and exposed suspension rubber and plastic parts. Note that the product needs periodic reapplication to maintain full protection.
A similar more recently available product is 303 Automotive Protectant which hails from the USA, where UV damage is stronger in many States than the UK, but it offers the same types of protection that the Autoglym product does for a very similar reasonable cost, so it’s definitely worth thinking of spending a little time and effort giving this sort of treatment to your cars rubber and plastic parts.
Another rubber-focused product is Castrol Red Rubber grease which is formulated to lubricate brake and clutch system rubber seals and other rubber components without degrading them as other petroleum-based grease/lubricants will. Do note that replacement polyurethane suspension bushes are supplied with their own specific installation grease sachets as again alternative lubricants may damage the polyurethane.
For winter storage periods when the harsher, damp weather conditions penetrate many garages, and we have seen more dampness than usual recently, can cause surface corrosion in various metal surfaces, such as rusting of steel exhaust shields or white corrosion dusting on alloy components. I suggest spray-on Anti-Corrosion Formula ACF 50 could well make springtime preparation to bring the classic back into use a less strenuous job.
Not only is a damp or wet storage area for your car not good, but at the other end of the scale if it is too dry, such as a centrally heated integral garage can see rubber components dry out and start cracking earlier. Finally we know exercise is good for our body’s health, remember it is also good for our cars well being too!
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At MGOC Spares, we provide dedicated parts and accessories for classic MG vehicles, including the MGB, Midget, MGC and many more.
With thousands of products in stock, we are your one-stop shop for all your classic car needs. Our wealth of expertise means that you can trust us to find the right part for your classic MG vehicle – whatever it may be.
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