scraping sound when steering is turned to extreem - PeachParts Mercedes-Benz Forum

ktlimq · #1 10-10-2003, 11:23 PM

When steering wheel is at the full right or full left position,
I hear scraping sound.

When I turn the wheel a few degrees so that it is no more at the extrem left or right position, the noise disappers.

1992 Mercedes 300D

It picked up the car from dealer yesterday. The dealer did the following:

if the steering wheel is tapped or hit or roads are bumpy, steering wheel makes metalic rattle noise.
REMOVED AIRBAG AND SECURED STEERING WHEEL

The rattle sound disappeared after dealer fixed it, but the "scraping" sound came new after dealer fixed the "rattle" sound.

Power steering fluid is between min and max.

Duncan UK 190 · #2 10-11-2003, 10:49 AM

I think when the wheel is on full lock any further movement causes the power steering pump to work very hard.
My car does the same thing, not a scraping sound more of a whine. My friends volvo does the same thing.

ktlimq · #3 10-11-2003, 11:46 PM

May I ask which car you have?

It is somewhat vage whether it is scrape or whine.

The scrape I mentioned is less loud than the diesel idling noise (of course its tone is higher than the diesel idling noise).

Duncan UK 190 · #4 10-12-2003, 03:44 PM

Mines a 91 190e. Mine makes a quiet high pitched sound at full lock . I think if there is a loud noise then maybe it needs adjusting.
I wouldn't worry about it if it only happens at full lock.

ktlimq · #5 10-13-2003, 06:04 PM

Thanks.

In my case, I notice the noise after my car was at the dealer for steering wheel tightening and front struts replacing.
I hope they do not charge new labour cost for this scraping noise.

ktlimq · #6 11-01-2003, 07:49 PM

The scraping sound became significantly quiter a few days before the appointment with the dealer on 10/16/2003.

The dealer found nothing wrong in power steering.

However, the scraping sound became loud again a few days ago.

csnow · #7 11-01-2003, 08:15 PM

Your car has a adjustable stop on each side to set max turning angle. If I remember right, the rotor can hit something if this is not set properly.
Worth checking out.

ktlimq · #8 11-01-2003, 09:14 PM

The noise comes even when the car is at rest, if the steering wheel is at max turn position.

Kestas · #9 11-01-2003, 10:42 PM

I don't think you have a problem. Duncan is correct in saying the power steering system works very hard at full left or full right. It's never a good idea for any car to hold it tight against these positions. I believe these positions develop a pressure spike that isn't good for the system. Your car may simply have developed a different character of noise under these conditions after new struts were put on.

ktlimq · #10 11-03-2003, 03:33 PM

Today, it is quieter. The noise is intermittent. Some day I do not hear it, other day I hear it.

Whenever the steering wheel is at the extreme position, I hear SOME sound.

Some day, it is comfortable SHHH sound.
Other day, it is annoying high tone: it sounds like metal pieces scratching each other.

Because there are days with comfortable SHHH sound, I feel that the high pitch metallic scraping sound indicates some problem.

manny · #11 11-03-2003, 04:34 PM

Disclaimer.

I am not a P/S expert, but most power steering pumps have an internal by-pass valve.
Their job, as the name implies, is to relief the stress on the pump when you go to full-lock.
Could be an early warning sign.
Hell, I don't know, maybe a real expert will chime in.

P.S. If Gilly tells you it's busticated, shop around for a replacement.