Milano AC compressor mounting - question

["John D. Fox" <jdfox@domain.elided>]

OK, I have a question for those who have mounted or looked at the factory
AC compressor mounting on the V-6 engines. My car is an 87 model year
verde - it has 55K miles, and I've had it since 1990. I don't think it has
ever had any moron mess around with the compressor mounting.

I noticed last night when changing belts that the AC compressor seems to
have some play in its mounting to the block - enough that it could be
rocked up and down a millimeter or so. In looking, it is clear the
compressor ( a sanden rotary) is secured to a heavy pressed steel mounting
plate with three fasteners - this looks very secure ( whether it should
have all four mounting ears of the compressor held is question #1).

But, the steel mounting plate itself is fastened to the engine block
through two fasteners. On the outboard side, the steel plate has two
formed edges ( ears), which invert and have two holes, and allow a long
bolt to locate the front and back of the mounting ears on a big extension
of the block. This looks great. ( it may not be a block casting itself, it
may be some external iron or alloy casting that is also attached to the
block) in eather case this looks just fine and is rock solid.

But, on the inboard side, there is a very unusual stud-like mounting,
which the steel compressor mounting bracket is located on. The top of this
is threaded, and it has a hex head partway up the shaft. The AC
compressor bracket has a hole to pass the upper threaded portion, and it
has then a washer and nut to fasten the AC bracket to the upper
portion of this special pin. This too looks OK.

This stud/pin must carry the reaction torque of the compressor drive. It
looks like the design has a special threaded mounting pin, which threads
into the block casting, and uses a big cylindrical spacer between the
block and the stud/pins hex head. I'd guess the idea is that this pin is
torqued on the block, compressing the cylindrical spacer, and locking the
mounting to the block. You then fasten the AC bracket to the upper part of
this stud/pin.

However, on my car the stud/pin is loose in the lower mounting at the
block. If I loosen it all up, I can wiggle the clyndrical spacer and pin.
It doesn't feel like it is threaded into anything in the block. This
looseness is what is giving the whole compressor a little freedom - even
when tight the whole assembly can move around, as the pin doesn't seem
secured at the block.

I couldn't pull it all apart, as the AC compressor is charged, and the
motion I can get on the AC hoses is limited. ( and not wanting to really
pull on the flex hoses in any case). Has anybody taken one of these
mounting points apart? Do I have a fractured pin with some portion still
threaded in the block? Or is there some other mounting of the support pin
in the block? Is it supposed to float? This seems funny.

Thanks, I look forward to somebody's experience. Otherwise I'm going to
have to get the thing pumped into a clean can saving the R-12, etc. pull
the compressor just to take off the bracket and see what this is. Of
course, if it is a fractured pin, getting it out in situ might be fun,
too.

                                                           John
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