The picture below shows the rear engine support insulator for a '41.? The parts book says the insulator part number is 694164 (upper) and 690345 (lower).? The '39 - '41 parts list also shows an Engine Rear Support Insulator Retainer (Lower) part number 690347.? I don't know why the '42 to '48 doesn't use the retainer as those cars apparently used the same rear engine insulators. The Crysler and Dodges for this same era used an insulator that needs to be vulcanized to some kind of core.
My questions:
The upper insulator shown below (one intact the other with part of the insulator torn from the retainer) shows the retainer on the bottom of the upper insulator.? The catalog denotes the retainer as "lower" (see above).? ?Does the parts list mean the "lower" insulator or the "bottom" of the upper insulator?
The upper insulator is stuck to the retainer as if it might have been vulcanized.? Is this "vulcanization" due to normal use under the engine or was it manufactured this way?
Thanks in advance for the expert advice.? I've already heard a lot of speculation around the shop...just hope some one has the definitive answer.
I have seen both types of upper mount used, I think most mounts have a retainer or stiffener vulcanized in it although in '38, when they first started to use this type of rear mount, a cup shaped retainer was part of the rear cross member. Later replacement mounts were of a much harder rubber and do not seem to have any steel embedded in them. The thinner of the two rubber washers goes on the underside of the crossmember.
What is very important on these mounts is the upper steel washer which the engine actually sits on. It has a tubular sleeve through which the mounting bolt fits. This tube prevents the rubber mount from being compressed when it is tightened up. The bellhousing never sits directly on the rubber. dp