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Signs Your Rubber Mounts Need Replacing

An engine mount’s primary purpose is to secure an engine to the anchor point while absorbing shocks and vibration when in operation. Understanding when your traditional rubber mounts need replacing is key to a smooth engine experience. Rubber mounts usually have a lifespan of at least 5-7 years, depending on the application. It is still ideal to get them checked regularly when the engine is getting serviced or work is being carried out. Below, we outline some key signs of damaged rubber mounts.

Being aware of common symptoms of damaged or worn rubber mounts will help you identify if and when replacement mounts are on the agenda:

  1. Increased Vibrations:

One of the most common symptoms of damaged or worn rubber mounts is increased vibration during operation. If you notice that your engine is making more noise or you feel more vibration than usual when started, this is a key sign of worn rubber mounts that may need to be replaced. When rubber mounts are damaged or worn, the anti-vibration properties weaken as the mount can no longer perform at 100%. An increase in vibration leads to the engine making more noise, causing damage if left for an extended period.

  1. Rough Start:

Upon starting your engine, you may notice an excessive lurch that doesn’t feel right. This is another common symptom of damaged rubber mounts. When running, it may steady into a constant vibration, another telltale sign. You may also experience a lurch when turning the engine off.

  1. A Rough Ride:

Another common sign that replacement mounts are due as a result of damage is a jolt caused when changing gears. It is also noticeable when the engine is working harder under load. If your engine doesn’t have the same smooth feeling, a worn rubber mount could be the cause.

  1. Excessive Noise:

Excessive noise from the engine is a by-product of failed rubber mounts due to the increased movement causing the engine to become misaligned and contact other components. This can lead to impact sounds that become quite noticeable.

  1. Visual Wear:

With use, rubber mounts do change in appearance. However, the rubber mounts will likely be worn if significant corrosion or cracks are seen. If any cracks or crumbling to the rubber mount properties are noticed, it will limit its performance depending on the severity and root cause. The effectiveness of mounting systems relies on their form and shape, as any changes can damage the engine. If you notice any visual wear on the rubber mounts, replacement mounts should be top of the agenda.

When replacing rubber mounts, it is always recommended to replace them all at once. When one rubber mount is damaged, more pressure is pushed onto the remaining, usually causing them to work harder and accelerate the wear.

Poly Flex engine mounts are a high quality, high performance, durable and robust true marine propulsion mounting system designed with sufficient vertical deflection to obtain proven vibration isolation with minimum thrust and lateral deflection under load and inertia due to conditions.

Made from high-quality engineering-grade polyurethane, these mounts prevent rust and are resistant to oil and fuel. They are designed to isolate vibration across the rev range without compromising the alignment of the driveline. They are designed as a fail-safe system that is capable of holding the same weight inverted to avoid the engine tearing away from its anchor point in rough conditions or in the event of a capsize.

Poly Flex mounting systems allow for easy replacement of the core and hardware, limiting the need to replace the whole unit. They control thrust in all directions due to the core design being 360 degrees and can handle shock upon impact due to a 400% stretch factor in the polyurethane base material. All the metal components are coated in SA5 Cobalt Zinc, inhibiting rust for extended life, and due to the polyurethane design, no electrolysis occurs between aluminium and steel structures.

All Poly Flex engine mounts are Det Norske Veritas (DNV) type approved for vessels in survey. Poly Flex has been providing Australian-made quality and performance that is second to none since 1981, and with a strong focus on customer service hope to continue for many more years to come.

Click here to contact the team at Poly Flex today for more information on why our mounting systems are second to none and should be your first choice when replacement mounts are on the horizon.