Murphy's Law - George Murphy
Ask George:
Creaking Noise in My Roadster and Noisy Squeaks on My Windshield
Steering creak on 560SL
Q: I own an '88 560SL that emits a creaking noise when the steering wheel is turned at low speeds. All ball joints, tie rods, etc., were replaced. I want to replace the idler arm bushings. Can I do the work on wheel ramps, or is it necessary to use jack stands?
A: Wheel ramps or jack stands will work equally well as long as they are not in the way. I use jack stands so that the wheels are off the ground and the steering linkage can be moved easily.
The intermediate steering arm bushings can dry out and cause creaking noises when turning at low speeds. The arm is attached to a journal located on the right side of the undercarriage "frame" below the engine. The arm pivots on a bolt secured in the journal by a system of bushings (see Figure 1). The steering arm should move easily by hand with the wheels off the ground, but in some cases, the pivot bolt can be bound tightly, preventing free movement.
The necessary parts are found in a kit available for this job: No. 124-460-01-19. The dealer wants approximately $64 for it, but it costs $29 plus shipping at Performance Analysis Co.
The kit contains a new bolt and nut, plus the bushings and washers needed to replace all the moving parts in the mechanism. Reference to the M-B shop manual showed a number of (no doubt expensive) special tools needed for the job, but I decided it could be done without these using a little imagination and a big hammer.
The first part is easy: Undo the nut (9) from the bolt (1) and remove the bolt. Be sure to note whether or not your car has washer (3) installed - it has to be there to maintain proper steering geometry on models so equipped. Next, remove the dust cap (8) and pull out the steel slide bushings (7) from the rubber mounts (7). You may need a drift to drive out the slide bushings. The rubber mounts can be driven out with a brass or steel pin - I used the old bolt for a driver and it worked great. You can drive out the top mount from below, but there is no room to swing a hammer above the mount to drive out the lower rubber mount. I used a 5/8-inch steel rod about 2 feet long to reach down along the side of the engine from above; a few blows from a hammer and the old rubber mount was out.
In this case, installation is not exactly the reverse of disassembly - you must be careful of the new rubber mounts. First, clean out the bore of the journal bearing with solvent and apply a light coating of white grease or graphite to help the new rubber mounts slide in. Push both the upper and lower ones into the journal as far as possible by hand, then, using the new bolt, nut, and some washers, tighten the nut until the mounts are seated in the journal. Finally, remove the nut, bolt, and washers.
The rest is easy: Lightly grease and press in the slide bushings (7) and reassemble according to Figure 1. Make sure the rubber lip on the rubber bushings encloses the steel slide bushings. Be sure to install washer (3) if your car was equipped with it originally. Torque the nut to 120 Nm (87 ft-lb).
Figure 1
1 - hex bolt
2 - intermediate steering arm
3 - washer
4 - sealing washer
5 - rubber slide bearing assembly
6 - journal bearing
7 - rubber slide bearing assembly
8 - dust cap
9 - self-locking hex nut
Noisy, streaky windshield wipers
Q: My windshield wipers are always noisy and streak the glass even with new rubber. Is there a good practice for wiper care?
A: Let's look first at the M-B service bulletin and then I can offer a few additional tips.
MBUSA Service Bulletin S-B-82.35/621a issued June 2, 2009, covers windshield washer system and wipercare.
Maintaining Wiping Quality and Controlling Noise: 1. Check the angle of the wiper arms as per appropriate WIS documentation. Wiper-arm adjustment outside the specified tolerance will cause noise and wiping complaints. Only use the Mercedes-Benz-approved wiper adjustment tool.
2. Check for wiper-arm physical damage. Replace the wiper arm if the clinch bolt is loose, the locking lug is bent, or there's a change in the spring length, which will alter the contact pressure.
3. If complaints are related to rattling, whistling, or chirping noises, check the mounting of the wiper arm. Loose wiper arms can lead to excessive rubbing.
Wiper Blade Quality: 1. Wiper blades may degrade more quickly when:
• Exposed to severe environmental influences such as heat, cold, ice, snow, ozone, UV radiation.
• Not used for extended periods of time (wiper profile deformation).
• Dirt and foliage falls on the wipers when they are in the rest position.
• Unsuitable cleaning agents or methods are applied.
2. Customer-induced actions that will degrade the wiper more quickly include:
• Ripping wiper blades from a frozen windshield. This action damages the microedge. In isolated cases the rubber profile may be disconnected. Do not loosen wiper blades from the windshield with an ice scraper. Use a deicer to melt the ice and snow.
• Using wiper blades on an icy windshield. Use an ice scraper to clear away ice.
• Bending or adjusting the actual blade in any manner.
3. A worn or damaged wiper blade may lead to increased lines and noises. Before replacing a wiper blade examine for defects and perform a system check on the wiper arm and windshield.
Maintaining Windshield Washer System: 1. During any amount of rainfall, use the windshield washer system to pre-clean before fully using the wipers.
2. Check all nozzles and openings of the washer fluid system for calcification or lime deposits and clean if necessary.
3. Ensure correct water/fluid mixing ratio is used. Using the incorrect mixing ratio in cold temperatures can cause damage to the windshield washer system.
4. Adjust any faulty nozzle settings.
My Comments: The windshield washer system is usually neglected until it rains, then you have no fluid available to clean off road grime, dust, and rain. Operating the wipers with a dry windshield can scratch the glass and rapidly wear out the rubber blades. You can usually find washer fluid in one-gallon bottles at most convenience stores, or you can mix your own, like I do. Keep the reservoir filled so that you always have plenty of fluid for those sloppy days in heavy traffic that really challenge your view through the windshield.
Clean the windshield, wipers, and headlights every time you refuel - most places have windshield cleaning tools and paper towels. After cleaning the glass, raise each wiper and clean the glass where the wiper parks when off. Then use the damp portion of a paper towel to wipe off the rubber part of the wiper that touches the glass. Your wiper blades will last longer, and there is less chance of scratching the windshield with a dirty wiper blade.
To get a really clean windshield, make a paste of Tide laundry detergent and rub it on the glass to remove the silicone that builds up from rainy-day driving in traffic mist, which carries the silicone from cars that have gone through the car wash with the "Shine" or "Wax" button selected, an action that sprays silicone on the car to make it shiny. In heavy rain, the stuff washes off and ends up on your windshield.
Rinse off the Tide and clean the glass with any good glass cleaner, or simply use a vinegar and water mixture until it is squeaky clean. Wipe off your wiper blades with a wet paper towel after cleaning your windshield every time you fuel up so that the wiper rubber stays clean. Otherwise, the first wiper swipe on a rainy day carries accumulated dust and debris across the windshield and causes minute scratches.
After you've scratched your windshield with dirty or worn wipers, there is not much you can do to remove the scratches other than replace the glass. It seems that after so many years, the glass becomes pitted from the thousands of small rocks and sand particles that bombard it over time, so glass replacement is the only option.
For a new glass, I would use ample amounts of glass wax to help reduce pitting, but eventually even that wears down. It's a good idea to wax the glass every time you wax the car.
George Murphy is a Director at Large for MBCA and chairman of the Technical and Restoration Advisory Committee. Email George at [email protected].