Winter, Salt, Rust..what to watch on a w124? - PeachParts Mercedes-Benz Forum

awsrock · #1 11-03-2008, 12:25 PM

Hi all,

So since it will begin snowing soon (as more and more winter posts are coming up) I was wondering how I should go about ensuring that my 87 300D stays rust-free. It got to live in Florida up until about 3 years ago!
I know I've heard of zinc coating, but was that for the body, or for the underside, or both? My car does not have the original paint on it, and I don't know what quality the repaint was, as it was done by a previous owner.
What areas should I pay the most attention to? Are the w124s prone to rusting? (I don't see too many that have any)
My last car was a 91 Cougar and it rusted out on my in about 5 years, although I could have taken better precautions. (And, it was a Mercury..)
I don't have the resources to get a winter beater, either.
Would putting mudflaps on help at all?
Any wax recommendations? I hear that synthetic waxes might be better than carnauba, but I guess any would be better than none.
Luckily I live near a university, so they are pretty good about clearing the streets quickly, and snow doesn't stick around for very long here. They also seem to be toying around with some kind of liquid snow melter instead of salt, although I don't know if that holds any corrosion benefits.

Thanks

asnowsquall · #2 11-03-2008, 12:40 PM

Metal loves oil, so I use bar and chain oil like you use for your chainsaw. Works great.

Jeremy5848 · #3 11-03-2008, 12:48 PM

Somewhere I read that undercoatings can trap water and salt and in some circumstances actually promote rust rather than prevent it. In any case, getting old cars like ours clean enough to undercoat may not be possible.
You don't mention a garage so I'm guessing you park outside? Any chance of renting an indoor or covered parking space?

When I return from visiting snow country, I wash the car thoroughly, including the underside. I recommend washing the car weekly, including the underside, and applying a good paste wax at least once a month if not more often. When you have a nice day, open the sunroof and make sure it the seals are sealing properly – ditto the windows and the trunk. Snow and ice that sit on the car for long periods of time are not good as the melt water seeps through even the tiniest cracks.

Jeremy

awsrock · #4 11-03-2008, 12:55 PM

Quote:

Originally Posted by Jeremy5848

You don't mention a garage so I'm guessing you park outside? Any chance of renting an indoor or covered parking space?

Yep, apartment parking lot, and no chance of a garage. However, this could only be the case for one year. The girlfriend and I are thinking about moving out to the Davis / Sacto area if we can find jobs. If we don't, I'll be sure to get an apartment that has a garage in the Chicago area for a year (or any other area that we happen to go to that has snow) I'd enjoy not living in/near Chicago anymore, but that's where family is, so we'll see.

TylerH860 · #5 11-03-2008, 12:59 PM

Hopefully, you have a garage to park in so the car can dry off.

When I briefly lived in Colorado, I rigged a hose to a hot water line and blasted the stuff off a few times a week. The hot water made it kind of enjoyable. If your fastidious enough, you could hose it off every evening, then leave it in the garage overnight. That would give the car at least 10 hours of dry, salt free recovery time a day.

*edit* oops, apartment parking lot.

awsrock · #6 11-03-2008, 01:05 PM

[quote=TylerH860;2010507When I briefly lived in Colorado, I rigged a hose to a hot water line and blasted the stuff off a few times a week. The hot water made it kind of enjoyable. If your fastidious enough, you could hose it off every evening, then leave it in the garage overnight. That would give the car at least 10 hours of dry, salt free recovery time a day.
[/quote]

Well, I know my grandpa is always filling up a bucket and wiping off the lower side of his car, but he has a garage. With the exception of February-early March, it usually gets to or above freezing (although not by much) every day so I might be able to do a quick wipe, in addition to a weekly car wash. Hell, sometimes it is in the 50s. I long for some consistent weather

TylerH860 · #7 11-03-2008, 01:08 PM

I believe the rust proofing on W124s is MUCH better than W123s.

C Sean Watts · #8 11-03-2008, 02:16 PM

From the old stuff I've been able to read, they were also cold galvanized. What we've seen working on mine in my cousin's body shop - the bad part on 124 and 201 types seems to be inside the back of the jack holes, not what you see on the outside but within the rocker panel. Small places with fastener holes should be checked. If you take out the plugs along the bottom of the rocker panel and rear wheel tubs you can use your favorite oil/wax/anti rust mix. Also, check this...http://www.geocities.com/wallaces_21/waxoyl.html

I have not tried it yet but it sounds good.

babymog · #9 11-03-2008, 02:41 PM

The 124 is much hardier than the earlier body cars, but not impervious.

As far as waxing, washing down the lower half with warm water, checking window seals, ... sorry guys, but what you'd expect from non-salt folks.

The bad news is that the liquid snow melt, is a salt in water. It is cheaper to melt snow that way than the rock-salt, and it will get everywhere in your car.

Where you need to clean, is basically everywhere you don't see. If you can see it, and it's painted, the paint protects the metal.

Touch-up the car wherever it is chipped through the metal, that includes around fender lips and door bottoms. Get under the car if you can, be sure that every place where dirt and sand can collect (fender lips, suspension pick-up points, etc) are washed thoroughly to remove the salt-water holding dirt. The top of the car can dry, but dirt and sand deposits will stay wet 24/7. Clean all fasteners, apply oil or grease to exposed threads, they will be easier to remove some day.

Spray the inner-fender, rocker-panels, and floor behind the wheel openings with silicone spray. This will make it more difficult for the big chunks of ice to form and hang there. Wash out all of the leaves and things from below the battery box (remove the 124 battery box and vacuum beneath it, and under the center / blower motor housing). The more you remove in moisture-absorbing materials the better the car wil fare. Clean around gaskets and seals, and wipe the door & trunk seals with silicone to keep them from freezing shut.

Wash everything with lots of water whenever you can. If you don't have access to a hose, tough break, but at least use as much water at car washes whenever you can. Wash the top of the car, sure, but pay more attention to spraying under the car than over, the underside is where terminal rust starts and where the salt tends to stay. Some/most car washes recycle their water, filtered, but still with dissolved solids (soap, salt) so not all under-washes are great.

If you have an engine belly pan, use it. It makes a huge difference in how much salt water gets into the engine bay. Worth buying a new one IMO.

Garages are over-rated. If the car is cold enough for the ice and snow to stay frozen, it shoud stay that way until you are able to wash it. You put a car in the garage, the car heats the garage, salt and water melt and run around to new places, then the car and garage chill again allowing the same crap to re-freeze. Freezing tends to help salt exploit cracks and crevices by forcing them open. Plus, ice doesn't cause much corrosion compared to water.

If you drive around town, you get a lot of crud on your car. However, the crud in highway travel is arosolized (sp?) and as a gas can get everywhere from the heater core to the tiniest voids in the body. I compared the throttle-body on my '91 (never saw a Michigan winter) to the throttle-body of a year-round Michigan car, the year-round / salt-driven car had noticable corrosion INSIDE the throttle body, ... after the air filter!

Around trim clips, if the paint is breached, it will eventually rust. All holes in the body that you can check for damage, chips, etc. are worth checking. Terminal rust takes a long time to completely destroy, but a short time to start. I've seen serious rust on the 124 around the rear wheel openings, mainly from bad seals and missing plugs getting salt water and water into the trunk, and it standing in the wells behind the wheels or around the spare, or just condensing on all inner surfaces of the trunk. Rocker panels are worth protecting, they rust I'm told, though I've not (yet) seen it on a 124.

Hose it down as often as possible, underneath etc., and it'll last many years. One year of reasonable care will not even be measurable in rust, several years or serious neglect will. I've run many cars for a decade or more in the winter here, ... my first quattro drove every winter for 15 years or more with no rust, just a little washing once or twice a week.

Oh also: If at all possible, when starting out, I always tried to drive through some fresh snow to pack the fenderwells before hitting the salt. A little barrier to keep the brine from direct contact, and to dilute the brine when melting starts.

Best of luck from the other side of the lake.

awsrock · #10 11-03-2008, 03:05 PM

Thanks guys. As always, your help is appreciated.

Another question, doesn't silicone help rubber/vinyl degrade? I don't know much about different types of lubricants, but I recall hearing that somewhere. (maybe just not good for bushings, etc?) Would Meguiars #40 be ok on door seals? (Moreso, would it benefit it at all?)
I'll have to go pick up some silicone spray. I might tinker with some oil as a coat too.

Also: Is the underbody itself safe? I don't know what kind of coating is on there, but it looks pretty heavy-duty. Not like my last car where you could see everything and it was all exposed.

asnowsquall · #11 11-03-2008, 03:22 PM

Thats the beauty of bar and chain oil is that you never need to wash the underneath of the car again, and after a while the oil get into every location so that all you need to do yearly is spray a little oil where it gets washed off by the tires. I had a 535i daily driver that came from NC and the body stayed in beautiful shape.

It is drippy for a while but settles down. Spray it in the rockers and they never rust out.

bob_98sr5 · #12 11-03-2008, 04:22 PM

aws,

you want to see real world? look at my blog from beginning to end!

i have repaired with welding and some fiberglassing those rusted out areas. In short, the rust damage appears to start in several areas:

- bolt holes that help secure plastic parts onto vehicle. wheel well lining is a big culprit

- seams near wheel wheels. any seam for that matter.

- front and rear of rocker panels.

- anywhere under rear subframe

So what to do? Use a bright flashlight and poke around with an awl or a screwdriver. Look for raised areas of undercoating. after awhile, you'll spot them easily. that means that the moisture from the rust is coming through like a baby alien. scrape off w/ a heat gun and treat with POR15's system. for seams that are coming apart due to rust, open up a little and scrape out rust. treat accordingly w/ POR15 and then squeeze together and seam seal.

ideally, you want to cut out and replace with welding.

in the rocker panel holes, pull out a few and spray bottle some bar and chain oil. theres a big one up front you can access if you remove the front tires.

ive heard this is the cheapest, best way to prevent rust. seal up holes with brushable seam sealer. concentrate around the jackholes too.

Bob

babymog · #13 11-03-2008, 04:32 PM

Been meaning to ask Bob:

With the rust on your '87, is it cosmetic in the rockers, or does it affect the jack-point strength?

Fulcrum525 · #14 11-03-2008, 04:33 PM

I do a few things.
First is the annual pre-winter wax which is great because at this time of year it stay perfectly clean so long as I keep it dry.

Driving after the first and subsequent storms i'll hose down the outside (Particuraly the wheel wells) I'll also run it through a touch-less carwash if the salt starts to build up (Happens when it warms up during the day and gets sprayed onto my car by idiots in front of me driving through puddles)

I'll also try to clean it by hand if its just warm enough out. I've been known to wash my car in by hand in twilight when its just above freezing (40)

Going home during lunch and cleaning usually makes it less painful.

Jeremy5848 · #15 11-03-2008, 04:36 PM

It wouldn't hurt to thoroughly clean the underside of the car before snow flies. Dirt is great at trapping water, salt-laden or not, and holding it like a sponge next to those vulnerable metal parts. Actually, underside cleaning is a good annual project, snow or not.