03-05-2020, 08:04 AM
Over the years I have replaced several sets of rubber mountings on the engine of my RP ( it has a later 2brg rubber mounted crankcase). For minimum vibration and longevity I have discovered a couple of factors that are important in my view. Firstly, sort out the oil leaks because impregnation causes the rubbers to blow and split. Secondly, don't overtighten. That also exerts pressure on the top rubbers and reduces their life.
Last year I experimented with a set of polybushes turned from a length of poly bar. It is a harder compound than the rubber and supposedly fuel and oil proof. To this set of bushes I added a spring at the rear nearside. They lasted about a month before they started to break up.
So, after the engine rebuild I fitted yet another set of rubber mounts to an engine which now had been rendered oil tight. The mounting bolts, which are fitted with nyloc nuts were just done up enough to pinch the rubbers without crush. The car has done about 3000 miles since then with no apparent degradation. A result in my opinion. Centre rubbers still in place.
Last year I experimented with a set of polybushes turned from a length of poly bar. It is a harder compound than the rubber and supposedly fuel and oil proof. To this set of bushes I added a spring at the rear nearside. They lasted about a month before they started to break up.
So, after the engine rebuild I fitted yet another set of rubber mounts to an engine which now had been rendered oil tight. The mounting bolts, which are fitted with nyloc nuts were just done up enough to pinch the rubbers without crush. The car has done about 3000 miles since then with no apparent degradation. A result in my opinion. Centre rubbers still in place.