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Garage => Mechanicals => Topic started by: Jan S on 30 June 2021, 05:06 PM

Title: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 30 June 2021, 05:06 PM
This year's 3-week summer road trip with the W116 in danger  :o

A few days ago I noticed a leak in the high pressure power steering hose.

A workshop in the area suggested to put in a new rubber hose and mount it to the 10 mm and 8 mm pipes at each end (where the old hose was attached, but with new hydraulic adapters/connectors between pipes and hose). Sounded as a good idea. However, by pure mistake the mechanic cut the 10 mm pipe at the power steering pump inlet at the wrong spot. Ggrrrrrrr!

Now I'm in dire need of the hard line (part of the hose) at servo steering pump end. I don't need the rubber hose and the hard line at the steering box.

If you have this part around and would be willing to sell it I would ask UPS to pick it up.
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Randys01 on 30 June 2021, 07:32 PM
Get the local Pirtech or equiv mobile hyd hose repair service to visit you.
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 01 July 2021, 08:39 AM
I found the hose on ebay, and the seller in Germany have shipped it with 24 hours over-night delivery service. Fingers crossed the part fits my car  :)
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 15 July 2021, 05:20 PM
The hose fits, but leaks  >:(

The problem is the mounting surface between power steering pump (convex surface) and the high pressure hose (concave surface).

Both the pump and the hose surfaces have some scoring. When fit together it will not seal properly ..... probably.

How to fix this?

Any experience with sanding/polishing both surfaces? What tools to use?

Can this part of the pump be "reconditioned"?
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Alec300SD on 15 July 2021, 07:06 PM
Use a copper aviation conical crush washer to seal the union.
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: raueda1 on 15 July 2021, 11:17 PM
Quote from: Alec300SD on 15 July 2021, 07:06 PM
Use a copper aviation conical crush washer to seal the union.
And tighten in one motion without stopping or reversing.  Cu washers can be used just once.  Otherwise heat it to glowing with a torch and quench in water (annealing?).  Can you post a picture of the problem?
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 22 July 2021, 04:16 PM
Thanks to both of you for advice!

I will try to get some "copper aviation conical crush washers" when I'm back after the summer vacation (the summer road trip went down the drain  :( )

Alec300SD: How does a washer like the one you mentioned look like? Can you send a link to a picture?
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Alec300SD on 22 July 2021, 05:47 PM
https://www.amazon.com/Legines-Copper-Gasket-Degree-Fitting/dp/B07CHFJH38

You can also make them from flat washers.
https://www.youtube.com/watch?v=u7WULLs2nV8
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 28 July 2021, 01:22 PM
Great!

I included two pics. The first from the convex connection at the steering pump (outer thread is M16), the second from the hose/pipe flaring (the pipe is 10mm at base).

I'm a bit confused with the size of the washer. The Amazon-link says 1/2'' Tube OD .... OD probably stands for outer diameter. Do they mean the outer diameter of the washer? Will that washer fit the connection?

What do you think, Alec300SD?
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Alec300SD on 28 July 2021, 02:46 PM
The photo link was just to show what a conical washer looks like.


The half inch (outer diameter) conical washer probably won't fit as one half inch equals 12.7mm.
A 3/8 inch  conical washer (equal to 9.525mm) is probably the best choice if you can't get a metric washer.

https://www.ebay.com/itm/383968747295?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A151RTzscrTCGHCmEYrJuOcw11&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=383968747295&targetid=1262376589336&device=c&mktype=pla&googleloc=9031974&poi=&campaignid=12874531651&mkgroupid=123924950842&rlsatarget=pla-1262376589336&abcId=9300535&merchantid=127684781&gclid=CjwKCAjwgISIBhBfEiwALE19SYz4peCl3q46L8tts6RInx4ohYVoAj5n9KVPbp6t4lN6nJjjkNomOhoCmtMQAvD_BwE
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: 3l33ter on 29 July 2021, 10:41 PM
I'm glad to now know that conical washers exist.

I guess the scoring happened when the fitting was tightened down with some dirt/debris in there.
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 30 July 2021, 02:11 PM
Perfect - I ordered both 3/8" and 1/2" to be on the safe side.

Thanks!

I will keep you posted how it goes.
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 19 August 2021, 02:28 PM
The 3/8" conical copper washer finally arrived and fitted perfectly, it seems (the 1/2" washer was to big).

I did a short test drive tonight and couldn't see any leakage. I guess I need to monitor the situation closely for the next weeks and months. So far so good.

Thanks for the tip, Alec300SD!
Title: Re: URGENT - need help with high-pressure power steering hose
Post by: Jan S on 28 September 2021, 04:34 PM
The copper washer works fine -- no leakage!