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Steve1966 · 12th February 2018, 11:21

The original Rover hydramounts fitted were essentially the same dimensionally but the rubber hardness was different for the 3 engine types due to the differing engine weight which needed to be supported.

The 1.8 (blue paint spot) was 115 N/mm
The V6 (green spot) was 130 N/mm
The diesel (yellow spot) was 160 N/mm

These rates were designed to give approimately 8mm deflection due to the weight of the engine.

So, you could fit stiffer mounts to the lighter versions but I wouldn't fit either of the petrol mounts to a diesel as they will be less durable and may sink so low that they sit on the internal snubber increasing noise and vibration. The stiffer mounts will have noise/refinement penalties on the lighter engines but they will work.

On the MG versions we mixed things up a bit to increase the noise on purpose to give a more sporty sound but I can't remember what we did exactly. It was probably the V6 mount for the 1.8, and the diesel mount for the V6 and Diesel.

Steve.

12th February 2018, 11:21	#3
Steve1966 Loves to post 2000 W Rover 75 Saloon 1.8 Man Club (SE) Join Date: Mar 2012 Location: Warwickshire Posts: 436 Thanks: 66 Thanked 95 Times in 48 Posts	The original Rover hydramounts fitted were essentially the same dimensionally but the rubber hardness was different for the 3 engine types due to the differing engine weight which needed to be supported. The 1.8 (blue paint spot) was 115 N/mm The V6 (green spot) was 130 N/mm The diesel (yellow spot) was 160 N/mm These rates were designed to give approimately 8mm deflection due to the weight of the engine. So, you could fit stiffer mounts to the lighter versions but I wouldn't fit either of the petrol mounts to a diesel as they will be less durable and may sink so low that they sit on the internal snubber increasing noise and vibration. The stiffer mounts will have noise/refinement penalties on the lighter engines but they will work. On the MG versions we mixed things up a bit to increase the noise on purpose to give a more sporty sound but I can't remember what we did exactly. It was probably the V6 mount for the 1.8, and the diesel mount for the V6 and Diesel. Steve. __________________ Jobs Done since (Apr 2012): Spyhole, Thermostat, IMG (x2), Front ARB Drop links (x3 pairs), Rear Damper, Coils/HT Leads, Heater Matrix, Unions, 13x tyres, Gearbox Oil, Full Service (x3), Water pump & belts, LH/RH lower arm & bushes, Front/Rear pads/Discs, Fr door finishers, Track Rods, Jule's intake tube, Clutch, Slave, DMF (ouch), 1 1/2 exhausts, front springs/top mounts, Jule's Fan upgrade/condenser, reverse gear switch, OSR upper arm, spring, and sill welding. 78,000miles (175,600m total). Last edited by Steve1966; 12th February 2018 at 11:25..