How to Quiet a Rattling Shifter in your Milano
by Dan Przybylski
Besides the many other problems that plague the Milano, also known as the 75, some Milanos had a unique characteristic of a rattling shifter. While the Milano can be a terrific cruiser on the road and a formidable sleeper at the light, it can be an obnoxious and noisy pinball game complete with bells, buzzers and too many blinking lights so reminiscent of those exciting creations of Midway, Inc. Often it is these seemingly minor nuisances that can make a car seem like junk when all that's really needed is a little (or maybe even a lot) of care to correct a problem that doesn't actually hinder the car's performance but makes its operation unbearable. I found the shifter of my Milano to be one of many slight malfunctions that added up to make this world class car sometimes seem like a lemon.
Just another Sports Sedan
The Milano is of course based on the rear-mounted transaxle and de
Dion suspension originally introduced with the Alfetta. The clutch, gearbox,
differential, and even the rear brakes are a single unit mounted to the
body to constitute the rear axle along with a symmetrical pair of constant-velocity
jointed half-shafts driving each of the rear wheels mounted upon a solid
and empty tube positioned by a Watts linkage for the rear suspension, you
know! So unlike the familiar spiders and pre-Alfetta GT's from Alfa, the
shifter is not part of the transmission.
In fact it's no where near the transaxle of the Milano. The shifter is suspended from the body in front and is attached to a rod that spans back to the transaxle. When you push forward on the shifter for either first, third or fifth gear, the rod is pushed back because the other end of the shifter is on the other side of the fulcrum. When you pull back for second, fourth or reverse, the rod is pulled forward. However, this is only one dimension. To differentiate between first and third for example, the rod is twisted. It doesn't actually twist implying strain, but instead rotates along an axis parallel to that of the direction of the car. It's the combination of these two motions, rotation and longitudinal motion, that allows the remote shifter found in de Dion based Alfas.
Threading the Needle
This is accomplished by a slightly under-engineered coupling in the
remote shift linkage. Most people think of problems with their transaxle
shift being caused by a problem with the coupling back at the transaxle.
While not impossible, there can also be problems with the shifter up front.
And this can lead to a sloppier shifting Milano or an obnoxious, grating
buzzing caused by otherwise expected vibrations in the drivetrain, but
made audible by this loose coupling.
On the end of the shift handle opposite of where your hand goes there are two flat extrusions that make the bottom of the shift handle look like a tuning fork. The rod going back to the transaxle has an eye like a needle. In that eye, is a bushing that is supposed to be packed with grease and supposed to have o-rings on either side. Either tine of this fork attaches to either side of the bushing and there is a 6mm bolt and nut that holds the bushing between the fork. The bushing turns in the eye of the shaft. When properly operating, the bushing, the fork part of the lever and the bolt and it's associated hardware will be in effect one piece of metal. That is to say that they will not move relative to each other. The only part of this linkage that will move is the bushing relative to the eye in which it resides. This allows for the forward and back motion of the shifter. But because the bushing and fork combination doesn't allow motion along any other axis, the driver can move the shifter from side to side to choose from say second as opposed to fourth.
So What's the Problem ?
An inspection of the threads on the 6mm bolt can reveal a condition
that can lead to a loud shifter and eventually a total failure of the shift
mechanism. If the nylock nut is loose, then you've found your rattle. The
knee-jerk reaction is to simply tighten the nut, however if the threads
are flattened, stripped or marred on the bolt in any way, consider that
a good indication that the bushing is frozen in the eye of the shift rod,
and the fork and eye are turning on the bolt. In any case, even if the
bolt looks new, it's not difficult to inspect the condition of the bushing.
This is because after the bolt has been removed and the fork is moved out
of the way, the bushing can be poked out of the eye of the rod with your
finger but only if it is operating properly. If the bushing won't move
under moderate pressure from bare hands, it's because the bushing is frozen.
To get at this part of the linkage you need to go under the car over the catalytic converter, drop the couple of exhaust supports to allow the catalytic converter to sag a bit allowing more room and pull the heat shield out from under the car directly over the catalytic converter. Did I mention to let the car cool down ? The Milanos have huge catalytic converters which become very hot under normal operating conditions. I strongly suggest letting the car cool down overnight!
Only the front of the car needs to be raised, and taking into account that this endeavor has nothing to do with the suspension, brakes, or wheels, I would consider using a couple of work ramps. These can offer greater stability than jack stands, but before you rush off and buy a pair, try borrowing a pair. Test them by slowly creeping a ramp up to the front of your parked Milano's front tire. Does it contact the front spoiler before it contacts the wheel? Thought so. Even if it's close I wouldn't try it. You might find that driving the Milano onto work ramps creates enough compression of the front suspension to make the spoiler contact the ramps much less enough to make the spoiler make some really awful crunching noises.
Like Pulling Teeth
To remove a frozen bushing, one needs to fashion a puller out of a
socket and a long bolt and matching nut. You need to find a 12-point socket
that has an inside diameter that is slightly larger than the inside diameter
of the eye or outside diameter of the bushing. You place the nut side of
the socket over one side of the eye. Then you run the long bolt through
the bushing and the out of the drive side of the socket. You might need
a washer so that the nut does not pull through the 3/8' square drive hole
of the socket. Then you start a torquin? and a torquin?. The bushing should
be pushed into the 12-point side of the socket. If the bolt runs out of
thread, then get more room by stacking washer between the nut and the socket.
After the bushing is out Then you simply clean up the bushing and the eye. If the bushing was frozen, it's likely that it's not worn considering it wasn't moving. What is more likely to be worn is the bolt and possibly the shift handle fork. Inspect the insides. There is a possibility of round grooves worn however this is unlikely because the loose nut and bolt weren't applying pressure in the first place.
Lightly re-pack the bushing as upon inspection you will see that the bushing has helical flutes for grease, and replace the o-rings. I suggest replacing the existing bolt with a slightly longer one and use two normal nuts. Torque the first one down relatively tight and then torque the second one down against that as a lock nut. Make sure that you are using flat washers on both sides of the fork and a split-type lock washer on the side with the nut. The first nut tightens the fork against both sides of the bushing. The second nut keeps the first nut tight because the shifter vibrates, and that is probably what caused this problem in the first place. If you decide to stay 'stock' then replace the bolt if there is any indication of strain such as bad threads, and never re-use nylock nuts. Buy a new one.
You may find the shifter tight. This will loosen up, but if you follow this procedure, the shifter will no longer rattles regardless of any vibrations caused by your tires, guibos, or 10' sub-woofers. You may even find that the shift is much more crisp. And we all know that is vitally important for a de Dion based Alfa Romeo.