128 Sedan Rust Info

The following is a list of common places to find rust in a 128 sedan:

Swaybar Mount

Water pools in the swaybar mount on the inside of the engine bay because there is no drain provision. I believe water also finds its way into the box section that makes up the front unibody where the swaybar mounts are. The result is that it rots out where the mount attaches. Since the swaybar locates the front suspension, it is vital that it be solidly mounted. This also means that if the swaybar mounts and/or surrounding metal rusts, the suspension forces will quickly fatigue the already weakened metal.


Swaybar mount rust on my 128 Rally.

Battery Tray

Due to the corrosive nature of lead-acid batteries, the battery tray is a typical rust spot in any car. The 128s are usually in poor shape. What really makes the battery an enemy to the longevity of a 128 is that once a rust hole has formed in the battery tray, any spilled acid drips down from the tray onto the frame rail and swaybar mount area. When this area rusts, the structural integrity of the unibody is seriously compromised. When the front unibody starts to flex, all sorts of spooky handling characteristics occur, particularly very pronounced torque steer.


Rust on the battery tray, frame rail, and swaybar area in my Rally. If you poke the sheet metal to the right of the battery tray, behind the headlight, you can feel it flex (the undercoating is the only reason there isn't a hole).

Crossmember Mount

Above the front crossmember mount are a row of spot welds. Both of my 128s have had cracks here. The rust wasn't bad at all in either case, but it is a potential spot for rust and fatigue.

Spare Tire Mount/Engine Mount

I'm not sure how common this is, but my Rally had some serious fatigue issues around the spare tire mount/engine mount. When accelerating or decelerating (anything that would torque the engine) I would hear a "pop!" It took me a little while to figure out that it was the metal rubbing at the cracks. I had originally figured it was a worn clutch cable or clutch pedal.

Windshield

Cars equipped with the stainless trim around the front/rear windshields have a bad tendency to rust. It is apparently difficult to seal these windshields, so water gets in, collects between the body and stainless trim, and rust follows. I have yet to own a 128 that didn't have a leaky windshield. The mid-70s sedans had rubber moulding around the rear windshield which provided a much better seal. The late sedans (and this may have been a european-only feature) had both front and rear rubber moulding. An earlier car can be converted, but you need the glass as well as the moulding because the glass is slightly undersized to accomodate the thick rubber moulding.


One of the more serious cases of windshield rot I've seen.

Rear Strut Towers

Rust tends to for on top of the strut tower/wheel well. I'm not exactly sure why. The picture says it all.


Sorry for the poor photo... Anyway, you can see where it rusted under the sound-deadening material.

Floors

That nice thick sound deadening insulation does a wonderful job of soaking up moisture (especially if your windshield leaks!) and therefore promoting rust on the floors. Generally, the plastic backing on the carpet does a good job of keeping water from soaking through to the insulation, but not always. Also, the rubberized coating on the floors can separate from the floor, creating a nice pocket for moisture to enter and start forming rust. I found this to be a problem on my first 128, so I chipped up all of the coating to treat the rust.

Doors

The doors tend to rust along the bottom edge, which is usually evident by the paint bubbling up. The cause of this is typically that the drain holes in the bottom of the door get plugged up with dirt or old rubber soundproofing/undercoating. Sometimes they get plugged up enough that during the rainy season, the doors feel really heavy, and water may even spash out when you close the door! The simple remedy is to remove the door panel, scrape out all of the debris that has collected at the bottom of the door, and poke a screwdriver through the drain holes to clear them out.


In more serious cases, they even rust on the window sills.

I hope my 128s never look this bad! This was a parts car a friend and I picked up from a San Francisco waterfront area.


This page last updated: January 17, 2001
This page created: September 10, 2000
Courtney Waters courtney@mirafiori.com
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