tiller0627

what is the purpose of this hose other than causing a potential air pocket it goes from the pump to the subframe and is capped off on the end is this hose necessary or can it be capped off behind the banjo fitting

Welwynnick

Its a hydraulic vibration damper, that helps to smooth the pump's output. Its connected in parallel with the main pump output to the pressure regulator.

You'll find lots of help here, but please make it easy for everyone by using sentences.

Cheers, Nick

tiller0627

So in other word if it isn't on there it will mess the pump up?

Welwynnick

I wouldn't try to do without it. If its there, its there for a reason. It could be that its just to stop the ABC system from being noisy.

In any case its an easy repair. Just take it to a hydraulics shop and they will replace the failed hose for peanuts.

Nick

tiller0627

I have tried two different places today ,and neither had metric fittings. I was trying to get it going today , and besides the price of the hose I cant get one until next week. Just wasn't sure how important it was beings it doesn't go to anything.

tiller0627

Make that 6 places, nobody carries metric fittings. Any suggestions

Welwynnick

There are three ways I know of to fit a new hose into an existing pipe assembly:

1) Use a flared coupling. This requires the pipe to be flared (typically 37 deg), a bit like brake pipe termination but on a larger scale. Haven't tried it; seems to be a good solution, but needs metric fittings.

2) Use a compression fitting. No need for a flare tool. This is what I do, but also needs metric fittings. The hoses are 3/8", but the pipes are all 10mm or 12mm (at the pump outlets).

3) Something that was suggested to me when I tried a different hydraulic shop recently: WELD the new hose section into the existing pipes. I hadn't considered that before, but they were pretty confident of getting an accurate and reliable result. Nearly went for it, but I really wanted to keep the flexibility to fine tune the length and angle of the hose when I fit it (also makes it easy to fit another hose in the future - bolt in - bolt out).

If you can find somewhere that's experienced with pipe welding, I think you should be able to get round the metric problems - I'm sure you can weld 3/8" pipe to 10mm pipe. Its got to be done accurately, though. There's nothing that kills a flexible hose like twist.

Nick

slonar21

This is the only hose that you must use the Mercedes part, there is a spring/damper in it, a hydraulic shop will not be able to provide that damper. Without it you will feel a buzzing vibration in the car.

Welwynnick

Its just a plain hose. I still have my old one in pieces - there's nothing in there.

nick

tiller0627

The guy at the hydraulic shop did say there was something weird with the plastic line inside the hose. He wasn't sure why it was in there or what it was for.

Welwynnick

There are different versions of that hose. Perhaps you have a newer version than mine. Can you read the part number? Anything beginning with A220...? Can you post any clearer pictures?

tiller0627

a220 320 5372 That's the best I can do on the pics sorry.

tiller0627

I have also noticed the hoses I have been looking the part number is a220 320 53 72 07,dont know what the extra 07 is for.

320 dreamer

232$ free shipping from oediscountparts.com

tiller0627

I went to that site and put the part number in, and nothing was found.When I go to the model there is no cl65. Do you have the part number that is good for them?

tiller0627

Seems like the part store oediscountparts.com that 320 dreamer suggested is a pretty good place to deal with. I was having problems finding what I needed on there web site sent them an email, and had a response back within 10mins. with price part#, and when they could have it to me.Seems to me that is good service if anyone is looking for parts. Price seemed really good to @$232 for the hose I needed,eveywhere else was 3 to 4 hundred.Thanks again for the replies I have got being a newbie and all LOL.

320 dreamer

if you have the part # you can enter it and not worry about what car it fits. oediscountparts is actually mercedes benz of ashville n.c. i have dealt with them for yrs

Speedriven1

That hose is for dampening pressure and keep it consistent. Would not run the system without.

biker349

can anyone show where this hose is connected and what the procedure is to replace it.
thanks

Welwynnick

https://mbworld.org/forums/s-class-w...03-s600-3.html

Post 105 onwards.

biker349

nick thank you! that's some thread!! very involved, really long and great info. do you happen to know the part # for the hose? when i check the part # in this thread it appears to be wrong.

biker349

btw, nick that idea i read about cutting out the hose and just getting the new hose with compression fittings to fit the existing pipes seems fabulous. do you still recommend this.

Welwynnick

Absolutely. I started off by repairing one burst pipe out of necessity, and now I've gone on to replace all the hoses in the engine bay. Not only do I recommend it as a repair, but also recommend it for periodic maintenance. Don't wait for a hose to fail - cut it out while its still good, and replace it with a compression-jointed hose.

Firstly, hoses can't be expected to last forever, any hoses exposed to engine heat should be replaced every 5-6 years. Its not a hard and fast rule, but its about right. Its proper, preventative maintenance, like timing belts.

Secondly, a compression-jointed hose is easy to remove and replace next time. Its much easier than replacing the whole pipe assembly, which MB would have you do. You only have to replace a short section of hose instead of a whole pipe, plus the hose joints are often easier to access than the MB pipe terminations. Look at flexible brake hoses - they're easy to replace - that lesson was learned long ago - so why shouldn't suspension hoses?

Thirdly, replacing the hose gives an easy opportunity to add a thermal-insulating sleeve, which will better protect the hose from heat. I think the failure mechanism is typically engine heat raising the temperature of the hose to over 100 C. Rubbers and plastics don't last long at high temperatures, and the rubber that's gripped by the crimp will perish and fail under tension from the pressure in the hose, forcing the crimp joint apart. Its just a matter of time, and temperature accelerates the degradation.

I've been running compression-jointed hoses for two years, and they've never leaked a drop. I've now done ten.

I've always been comfortable with mechanics and electrics, but hydraulics and pneumatics are new to me, so I've done a lot of research recently on pumps, valves, pistons and hoses. Nobody, anywhere, will predict how long a hydraulic hose will last, but one thing I did learn is that there's a consensus that compression fittings are considered to be reliable. Although hydraulics are a novelty for cars, its a proven technology elsewhere, and the problems have been solved. The W215/W220 were the first mass production active suspension cars, and we've all been learning some things the hard way.

Nick

Welwynnick

Just a few cautions though:

1. Before cutting an ABC metal pipe, remove the paint by scraping and abrade it so its clean FIRST.

2. When you cut the pipe, make sure you leave the inside of the pipe free of swarf.

3. Be very careful to get the length of the new flexible hose right - you must never run flexible hoses in twist or in tension.

4. Its a difficult temptation, but never tighten the compression joints until everything else is fitted just right.

Nick