Thread: Engine Mount rubber work hardened?

I would expect the old to have compressed due to the load over time. This will stop them working as well as new ones.

In my experience with RRCs, they fail by the bond between the rubber and usually lower plate failing, then they rub up and down and wear away.

Regards Philip A

In my experience with engine mounts in general, they get softer over time. This was certainly the case with my Smart Roadster mounts which I replaced recently. I figure if a vehicle sits unused they may harden, but it's only a theory.

James.

This would have been my viewe, but I have been advised that while this applies to Rover mounts, the Isuzu mounts are very durable, and no improvement in vibration can be expected by replacing them.

In fact, as a general rule, engine rubber mounts, in my experience, remain serviceable until they either degrade, usually due to being covered in oil for a long time, or fracture, usually due to excessive loading, such as severe bumps. Hardening of rubber is usually a result of UV exposure, hardly a hazard with most engine mounts. However, durability can be expected to vary widely according to the exact rubber formulation, which is likely to vary even for the same part number.

John

Not as much work hardening but rubber perishes as it gets old, and increases hardness as it loses flexibility. Some engines respond well to new mounts being fitted, so long as they are genuine new not el cheapo aftermarket or old and perished from storage. V6 Commodores in particular sound very grumbly on old mounts, so does my wife's old Camry (new OEM mounts for that would cost as much as the car is worth but they are oil filled too).

provided they dont get exposed to oil they go hard, crack and can seperate from their mounting plates.

exposure to oil (including diesel) will cause them to go soft an mushy

Rubber goes hard with exposure to Ozone (O3) which is present at low levels at ground level. Gets made from normal oxygen mostly by electrical sparks, big as in lightning or small as in brushes on electric motors.

Coat rubber with diluted silicon and you prevent ozone and oil contact. Pretty simple.

cheers, DL

Originally Posted by 350RRC

Coat rubber with diluted silicon and you prevent ozone and oil contact. Pretty simple.

cheers, DL

Wont silicone damage the rubber? I have found this in the past.