My son in law, Matt Cotton, recently obtained a couple which he believes to be new old stock metalastic and he has advised me that they are offset by about 12 mm.
I have looked at the old used mounts that I have kept and have found that :
I have 7 in number used old ones that were manufactured by Metalastic and these have offsets that range from 2 to 6 mm with an average of 4mm. The question is, were they manufactured with a 12mm offset and have sagged due to use?
I have 3 other old used ones, manufacturer and supplier, unknown, that do not have any offset.
I have 2 new ones, again from an unknown manufacturer and supplier, which have an offsets of 7 and 8 mm
I am also aware that Steve Waldenberg has recently purchased a new mount and that has an offset that varies between 2 to 4 mm.
Having an offset does mean that there must be a right and wrong way up to fit the mounts but having looked at the official workshop repair manual there is no reference to having to do this. I have always replaced them to give the engine the maximum lift.
Prior to going to see Chris I had sorted through my box of engine mounts and had selected a couple of old Matelastick mounts and a new reproduction engine mount. The old mounts had all been in service and the majority had been removed from cars because the rubber to metal bond had started to delaminate. Chris used a Durometer to determine the hardness of the various mounts. This turned out to be very interesting, the old Matelastic mounts produced readings of 60 and 70, so it looks as if one was a 1500 mount and the other was for a 1300 or 1850 engine. When Chris tested the reproduction mount it produced a result that Chris had not seen before its initial value was between 70 and 80 but then it dropped to a lower value of about 60.
I told him how for a long time I believed that all the Over Head Valve engines used the same engine mount, a part number 158016, but that I was then told that the 1500 engine should have a harder rubber mount than the other engines and that the difference was distinguished for a period by a
coloured paint mark on the mount. The availability of mounts with different hardness seems to have stopped at some point in time and it is only fairly recently that I happened to look at the official triumph dolomite parts catalogue and discovered that original 1500 Dolomite engine mounts were a part number 149934 which I assume was manufactured with harder rubber.
I am looking for comments on (a) whether you believe the mounts should have an offset or not and if they should what the amount should be (b) were you aware that there is a right and wrong way up to fit the mounts? Plus do you agree that when the engine mount is fitted it needs to be fitted to give the engine the maximum height?
