Author Topic: Power Steering reservoir level should be?  (Read 350 times)

mrkozzy

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Power Steering reservoir level should be?
« on: 01 April 2021, 11:39 PM »
Hi all.

quick question?

To what level should the power steering reservoir be filled?

Mine is at  2/3.

I've noticed an occasional softening of the pedal which has me concerned.  It comes back immediately with one pump. There are no leaks from what I can see. 

Strange........   
MrKozzy

ptashek

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Re: Power Steering reservoir level should be?
« Reply #1 on: 02 April 2021, 12:46 AM »
To what level should the power steering reservoir be filled?
Mine is at  2/3.

If memory serves, there's a mark on the housing, but if there isn't 2/3 is about right.


Quote
I've noticed an occasional softening of the pedal which has me concerned.  It comes back immediately with one pump. There are no leaks from what I can see
 

That would be the brakes I assume? Different reservoir :)
That's the break fluid container on top of the brake master cylinder. There's a clear min/max mark on it.
What you describe would suggest a possible internal leak in the master cylinder.
1993 "Pearl Blue" W124 280TE
1988 "Arctic White" W124 200T
1979 "Icon Gold" W116 450SE (history, resto)

mrkozzy

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Re: Power Steering reservoir level should be?
« Reply #2 on: 04 April 2021, 11:49 PM »
Yes correct.
Think my mind was in the clouds when I worded that one!

So back to the issue.  The power steering fluid level is perfect. Thankfully because it had a complete kit put in 12 months ago. Thanks for the information.

Checked the break fluid reservoir and its nicely full. Exactly where it should be.
Checked all the lines, booster, wheels etc externally and couldn't see even a drop of fluid.  Everything was bone dry.

Had the brake fluid completely flushed and changed mid last year.

I'm going to go for a master cylinder "wear & tear problem" as my next port of call. It had a complete rebuild 25 years ago so perhaps it's "time has come" again.

Nothing scarier than pressing the brake pedal the other day and having it go half way down!


MrKozzy

ptashek

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Re: Power Steering reservoir level should be?
« Reply #3 on: 05 April 2021, 03:56 AM »
The end seal on what's marked as "piston 2" below is the most common failure point (ignore the pipe leak ;)). Typically the very end of the master cylinder is corroded due to moisture accumulating in the brake fluid, and if you go hard on the pedal the seal gets damaged eventually and starts internally leaking pressure back to the reservoir, giving the effect of a soft pedal.

1993 "Pearl Blue" W124 280TE
1988 "Arctic White" W124 200T
1979 "Icon Gold" W116 450SE (history, resto)

mrkozzy

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Re: Power Steering reservoir level should be?
« Reply #4 on: 21 May 2021, 11:50 PM »
Thanks for the "direction" guys.

It was the master cylinder after all.

It had just started to develop a sloooow intermittent  leak. Fortunately the problem was picked up super early.

Whilst looking for a repair kit,  I was lucky enough to track down a genuine MB unit from a supplier interstate, so I didn't hesitate in buying it.

Whilst checking the system, I also spotted  the 2 rear brake hoses were cracking on the outer layer, so I replaced them with new ones also.

I'm feeling better now!  Another problem solved.

Thanks Forum   ;)
 

MrKozzy