Fiat Dino Forum (FDF)

HI!

When I replaced my starter motor I thought it is a good idea to
also replace the engine rubber mounts.

I bought a reproduced part from H&N, but I noticed that it's measurements are
not 100% in line with the original part: the new parts are a bit higher
and wider. Result is that the engine now sits a bit (4mm?) higher in the
engine bay.
Also I changed the rubber mount of the gearbox (SP repro part). Here the rubber
was much harder than the original. Result is that the Gearbox now sits significantly
higher.

I would like to know if anybody else has replaced those parts and if yes if you
had any problems in particular regarding drive train vibrations.

Thanks

Bijan

I think it's difficult to compare an old and a new rubber part by it's dimensions (height).
Rubber is a viscoelastic material and therefore subjected to creep. So depending on temperature, force and time it will always deform. That original shockmount could have been the same height and that new one might become like the old one over time. I think if it's aligned in a way that when the engine and gearbox lower a couple mm over time it should be fine, the hardy disc and universal joint can handle some misalignment.
About drivetrain vibration, I have a Fiat 130 with the same gearbox/axle/cardan and I eliminated all vibrations by installing a new universal joint and balancing the shaft. The joint was free of play but turning by hand is something different than subjecting it to 180HP. So replacing the joint and balancing it made it drive like a new car. Just replacing the universal joint without balancing us useless

Hi Stefan,

thanks for your comment. You 're right, of course there is
some deformation of the rubber components in the long run,
so it's hard to say what are the correct measurements here.

However I am not sure if the alignment of the gearbox to
the differential is correct with the new parts. My old
gearbox mount was much softer and also damaged by
leaking oil from the gearbox so I had no choice but to
replace it. The Gearbox was hanging quite low, now it
hangs much higher and the output shaft of the gearbox is
definitely not on the same level as the input shaft of the
differential. Hopefully the U joint and the rubber joint
are able to equalise this. Otherwise I will have to modify
the gearbox mount by drilling two additional holes.

Cheers

Bijan