Motoring and workshop suppliers now offer a choice between rubber or silicone hoses and other flexible mouldings. Both materials share many qualities – or they would not be offered for the same jobs – but there are significant differences too. Before you choose, consider which of the following pros and cons are relevant in your engine’s case.
Silicone has superior temperature tolerance to rubber – a quality that makes it first choice in racing cars. Clean and well secured, it is also better at withstanding pressure and corrosion, and less inclined to perish from adverse weather conditions or slow atmospheric oxidation. This inertness and resilience means it is capable of outlasting rubber alternatives, so despite initially costing more, you could recoup the difference through its greater longevity.
For a full list of the material’s robust physical properties see https://www.azom.com/properties.aspx?ArticleID=920.
Fitting and removal
When swift servicing is an issue, especially in those awkward to reach corners, silicone is generally easier to slip on and off. It’s also simpler to cut to shape and size if necessary.
The downside is that for similar reasons, it is more important to ensure it is well-secured, so it cannot slip off. However, silicone components are often a little thicker than the rubber alternatives, so some brackets and clips may be too tight to get into place over them. In some cases, you may have to change those too.
Whilst the appearance of rubber hoses is perfectly standard, rubber doesn’t usually come in the range of colours available from silicone. Owners that take pride in the appearance of their motor with the bonnet closed may choose silicone so they can be equally proud of it with the bonnet up, but vanity isn’t the only advantage of bright colours. Colour makes the layout of engines stand out better – especially useful when you’re trying to find your way round it in poor visibility.
Silicone hose manufacturers like https://www.goodflexrubber.com/pages/silicone-hose-manufacture now carry a wide range of high visibility hoses and mouldings.
Silicone has a better ability to dampen vibrations and noises than rubber, and is less likely to squeak if it is likely to rub against other surfaces. This isn’t a common problem with rubber (in engines), but in some circumstances, it could be a valuable quality.