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Art Love

Australia
6226 Posts

Posted - 06/02/2010 :  08:46:59  Show Profile  Reply with Quote
So you see I have the valve in my left hand and the spanner in my right. What you in the USA call a flare wrench won't fit on the high pressure line until it is screwed right in, so what you see there is a standard 12mm spanner. It is much easier to use a standard spanner to turn the pipe end fittings after they will no longer turn with your fingers up until you need to finally tighten them which is best done with the pipe spanner(flare wrench). You can see in the last picture that I have got the first of the 3 A,B and E pipes started into the valve and in the next few pictures I am screwing the second and third pipes in using my fingers before running them down with the 12mm spanner and tightening them with the pipe spanner.

























So each pipe is tightened up with the pipe spanner with the valve still free from its bracket.

















Now with all the pipes tight, I am locating the first of the 2 bracket bolts.









Then the lock washers and nuts.













Then reattach the control rod and the job is done.









Then I thought I would shift to the left front valve which is the most difficult. There are 7 pipes to connect. This is a W112, so three of the pipes are in fact hoses with steel pipe ends which is a much "easier" job than on a 6.3 where all 7 pipes are steel and if anything, there is less room. So it should not have been too bad. Here is where it goes.





I thought I would start by screwing in the two end pipes, A at the far end and E at this end to support the valve while I screwed in the rest.





The obvious next pipe to screw in was the front high level pipe which is rigid, before screwing in the rear high level pipe which is a steel end on a rubber hose. After trying for half an hour or more to get the front high level pipe end to screw into the valve, I gave up and released both the end pipes in order to allow me to move the valve in every direction to try to get the high level pipe end to engage the thread. I had no success, so I took the valve out to the work bench to check the thread. I could not get a spare pipe fitting to engage the thread explaining why I could not do it on the car. After another 20-30 minutes of careful trial, I had the spare fittig engaging the thread. So I spent the best part of an hour on one fitting and the valve is still sitting aside awaiting installation. Hence my comments about what mechanics have to deal with on a daily basis with these old cars and why this job is a PITA more often then not. So I have done all I want to today. It also reminded me that the pipe fitting into the far end A fitting is rounded off, so that needs to be addressed anyway before the valve goes back in. It's late, so that's it for the time being.
Art
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werminghausen

USA
771 Posts

Posted - 06/12/2010 :  10:53:14  Show Profile  Visit werminghausen's Homepage  Reply with Quote
Art
you mentioned correctly that the sensitivity of the lever is dependent on how far in the A and E valves are screwed.
The sensibility has to be measured at the lever while the adjustment is done by screwing the A and E in or out.
It would be great to have the the set points in order to adjust the valves correctly.

In reality the set points translate in the tolerances for suspension adjustment.
If the car is parking and you push the left fender slightly down by your own weight: how much height difference is correct until the valve adjusts? Someone from Germany mentioned that the suspension is adjusting in the range of 1cm. I could try and do some math what 1cm change in height means in degrees of the lever.
I would be very grateful if someone has comments here.
Martin

Almost invariably, someone has pulled them apart at some time in the past trying ignorantly to fix the air leak that is usually due to failure of the centre seal in the pivot. When I pulled a spare valve apart yesterday to see if I could answer your questions, I found a cast of the valve body bore in silicone sealant in the A valve housing. At least the valves had not been Loctited in as I have found in the past and unscrewed without damage. Hopefully your friend at Bosch can access this information for you.
Art
[/quote]
Hi Art,
as I mentioned before I have built a test stand in order to test the operation of 3 old valves. I built a jig for in order to know at what angle the lever is during testing, then I connected the E /A /Stk with a special fitting in order to apply air pressure. For air pressure and measuring pressure I was using my A/C gauge set.
The setting I described (15 degrees +/- 2.5 degrees) are about what I tested on the 3 valves I have taken apart.
I am very sure that e and a valves were adjusted by Bosch - therefore the locking screw with the cross in the middle.
Unfortunately all knowledge about these air valves has faded within Bosch. The only sources are a handful of people on the planet trying to keep the secret.
Martin
[/quote]
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Ron B

Australia
11612 Posts

Posted - 06/12/2010 :  18:39:52  Show Profile  Visit Ron B's Homepage  Reply with Quote
It doesn't take very much movement of the car at all to make the valve adjust. As an example,when testing the valves for leakage with the exhaust hose method,the car must sit for several minutes to normalise . it can take around 5 minutes for the bubbles to stop. a slight push on the car will make the bubbles appear again as the car rises against the pressure applied( then released) .
Having had a few new unused valves,the arc of movement in the 'slack ' position seems to translate to an arm movement of around 5 mm.


quote:
12-14-2004, 11:49 PM #8
Tom Hanson
MBCA Member

What the heck, try to stuff a MB 6.9 liter V8 in it. What a machine that would be..
__________________
Tom Hanson
Orange County Section
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werminghausen

USA
771 Posts

Posted - 06/13/2010 :  21:05:30  Show Profile  Visit werminghausen's Homepage  Reply with Quote
Ron
if I take my +/- 2.5 degrees for tolerance and calculate the travel of the lever at the ball joint with a lever length of 85mm then I end up with about +/- 3.7mm of an arc (total 7.4mm). This is in the range of your 5mm. If the tolerance is tighter , about +/- 1.5 degrees then this would mean an arc of +/- 2.2mm = 4.45mm total.
As I mentioned before the 3 old valves I tested had about +/- 2.5 degrees of travel before the A and E valves were activated. It can be that the 'slack' is getting bigger with age and that the set points are tighter than +/- 2.5 degrees.
I am coming soon to the point when I assemble my 3 valves. I need to adjust my valves and I need to know the set points. Maybe something around +/- 2.5mm is not too far off?
It would be great if other people could give their comments.
Martin
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Art Love

Australia
6226 Posts

Posted - 07/03/2010 :  23:12:26  Show Profile  Reply with Quote
I got the A hose from Tom after I got back from Lode Fest and decided to install it. Here it is.





It is to replace the existing hose whose end fitting at the A fitting on the left front valve is totally rounded of. This is it looking at you end on with the extra hose strapped to its middle.





So I had a look to see where the other end of it was. I had already removed the windscreen washer bottle, battery and battery tray for access. Getting to it has to be one of the better PITA's. I knew it was bad in a 6.3: it is no better in the W112 coupe. Here are some pics.




It's up there in the dark!




There are three hoses at that fitting. You can clearly see the lowest one. The exhaust line is the one in the middle above it. So, lets have a look from above.

















I'm going to have to talk to Justin about some right angle spanners!! Anyone got any tricks for this? I've decided that it will be necessary to undo at least the top hose or the bottom hose to get to the middle hose, so, you guessed it, I've ordered new top and bottom hoses from Tom because I see no point in replacing the middle one and leaving the other two in these circumstances. End of progress with installing the left front valve for the time being.

So, on to the right front valve which is easier. Here it is rebuilt.





Here is where it goes.





The same as at the back, I recommend that you do up the pipe fittings onto the valve with your fingers to safely get all the threads started.









I should have put the bolts into the valve body before I started screwing in the lines. The lines were in the way when I did it next, but I managed. Start these threads with your fingers as well.





Screw the fittings in with your fingers as far as they will go, then do up most of the thread with an open 12mm spanner.









Then finish them with the pipe spanner (flare wrench).









Then tighten up the mounting bolts with the 13mm spanner and reattach the control rod and hopefully the job is done.





Art
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Chris Johnson

USA
3751 Posts

Posted - 07/05/2010 :  23:18:52  Show Profile  Reply with Quote
Hi Art,

I did those three lines on Luis' #10 car, and it is simply (unless you pull the engine out) a real PITA. I had the car up on the big trailer so I could get under it. Without that ability, I don't think I would ever do it again.

Chris Johnson
If you aren't constantly impressed with your car, then it needs fixing.
100.012-12-000790
100.012-12-000867
www.300SE.org
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Art Love

Australia
6226 Posts

Posted - 07/06/2010 :  02:02:30  Show Profile  Reply with Quote
Chris,
I agree, the time to change these hoses in either car is when the motor is out. Then you can sit where the motor goes and get to them. There is not enough room from any angle for me to get a standard spanner on either end and turn it. Justin has some crows foot spanners, I think they are called, that fit on the end of a socket extension. I'm hoping I might be able to do something with them or something similar.
Art
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Ron B

Australia
11612 Posts

Posted - 07/06/2010 :  18:21:59  Show Profile  Visit Ron B's Homepage  Reply with Quote
I just thought i should mention this , it looks like the arms on the torsion bar and the valve are not parrallel . You need to get the car sitting on stands at the reqired ride height and then with the valve disconnected find the center point of the valve with a guide pin.
the arm on the sway bar should be adjusted so it's parrallel with valves arm then adjust the length of the rod to suit. Another good reason to make sure the rear sway bar bushes are in good order because the arm wobbling around affects the valves function.



quote:
12-14-2004, 11:49 PM #8
Tom Hanson
MBCA Member

What the heck, try to stuff a MB 6.9 liter V8 in it. What a machine that would be..
__________________
Tom Hanson
Orange County Section

Edited by - Ron B on 07/06/2010 18:24:03
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Art Love

Australia
6226 Posts

Posted - 07/07/2010 :  01:25:11  Show Profile  Reply with Quote
Thanks Ron,
Currently the car is on stands with the axle hanging. I haven't altered the length of the rod or the fitting to the torsion bar, and the set up was correct before I removed the valve for repair, so I'm presuming it will be OK when it comes off the stands. I'll bear it in mind regardless.
Art
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Art Love

Australia
6226 Posts

Posted - 08/10/2010 :  21:28:23  Show Profile  Reply with Quote
All 3 new air hoses arrived and we found that in this 300SE W112 coupe, by removing the hand brake cable, we were able to change over the hoses. There was just enough room to get a 12mm spanner onto the "nuts" on the steel pipe fittings in the space across to the MFI to loosen them from above and then I could spin the hoses on their longitudinal axis from below and undo them while Justin held the pipe fitting with the spanner from above. The order was top, middle and lower.

We then reversed the process and while Justin held the steel pipe fitting into the bracket from above, I was able to engage the hose thread from below, spin the new hose on its longitudinal axis from below until it was firm, and then Justin tightened the steel end fitting back up from above doing the lowest one first, then the middle. The bracket has an inbuilt "nut" which stops the hose end fitting rotating when the hose end is fully engaged. With these W112 hoses which have different angled ends at the valve end, it is essential to get the hose sitting at the correct orientation to fit onto the valve before tightening up the steel line fitting at the bracket. This does not apply in the 6.3 because the hose has no angled pipe at the subframe end.

I had my stock of air line seals at Justin's shed and was one seal short for the last hose, so I have just done that last top hose myself today and found it practical to do it all from above. This top hose is for the high setting and has the least angled valve end pipe which prevented it getting caught up as I rotated it. I think it is still better to have a second person underneath if that luxury is available.

Here are some pictures with the new hoses in. These 3 are from above.













This is from below where the valve sits and you can see what I mean about the different angled ends and how they need to line up with the valve fittings on this W112 car.









The hand break cable is freyed (don't those ends stick into your fingers), so I am replacing it when the new one arrives from Tom. Now I just have to put the refurbished left front valve back in and the job should be finished.
Art
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Art Love

Australia
6226 Posts

Posted - 08/11/2010 :  02:00:23  Show Profile  Reply with Quote
It's a public holiday here today for our city's annual agricultural show. So, as the better half had a phone call from a friend and has disappeared for the day, I decided to bite the bullet and install the left front valve. I must say that the job has not improved over the last 20 years.

This is a much easier job on this 300SE coupe than it is on a 300SEL 6.3, but it is still a tedious job. With the new air hoses in place, I set about connecting up the various lines with my fingers to ensure no cross threading. Here is a picture after about 10 minutes work. Note that the 3 air hoses are a breeze compared to rigid pipes and are all part way in. Note that the high pressure steel line to the right side valve at the top left is in. As this is the most remote to reach, I threaded it first with my left hand with the valve totally loose in my right hand. That just left the 3 steel lines on the underside of the valve. You will note that the A and E lines from the other side of the front axle are partly engaged, but the B line in the middle to the bellows unit on the left is not engaged and you will note the subtle angle of that line to the fitting on the valve. You may also note that I have, by this stage, engaged the threads of the two retaining bolts for the valve without doing them up.





Here is the same thing looked at from a different angle.





Try as I might, I could not get that B line to thread. If you look at the picture two up, you will note that the B line is pretty much hard up against the E line giving me no ability to adjust the angle of approach. This car has spent most of its life outside my stewardship, and there are things wrong that I have not had the time to correct. The other current project on the car is repairing and replacing the hydraulic fan coupling which is the cause of the oil coating with attached dirt and grime all over the front subframe.

Getting back to the topic, I decided to go ahead and tighten up all the lines except the B line. Getting to the front high pressure line is difficult. On all these valves, even the rear one, there is no room for a pipe spanner on these two high pressure fittings and very little room for a conventional spanner. I had to get the spanner in from the front across the top of the subframe to reach it and then turn it an increment at a time repeatedly rotating the spanner 180 degrees to do it up as the spanner could only move a short distance before encountering the next obstacle.





Here is my hand at the front of the subframe on the end of the spanner that you can't see in the previous picture followed by the spanner again.









There really is no room there. The rear high setting inlet hose was a breeze in comparison. With everything tightened up, I still could not get that left B line to engage. So I decided to undo the line at the bellows tank at the other end so I could better adjust the angle, still to no avail. This particular line is impossible to extricate from the front subframe after the top control A arm is installed. This is a PITA because it prevents modification of the shape of the pipe on the bench. I really needed to adjust the shape of this steel line and the adjacent steel E line, so they were not against each other. I forcibly bent the E line a smidgen. I still could not get the B line to engage. I ended up undoing the fitting on the valve body which has a much coarser thread and engaging the steel line into that and then tried to engage the fitting back into the valve body. I then couldn't get the fitting back into the valve body. I finally managed to bend the B steel line to a better shape to avoid the E line and get the fitting back into the valve body. This all took about an hour or two - I wasn't counting.

So I finally had everything done up and the B line away from the E line, not metal to metal.





All I had to do then was to reattach the outer end of the B line to the air tank of the bellows unit. There is plenty of room out there to reshape the pipe to allign it properly and get the thread engaged. I still have to install a few rubber spacers on the lines where they are missing. I've reattached the control rod.





Now it is a case of finishing the other projects on the car, firing it up and seeing if I have done the job properly and the car stays up. I hope that members have found this useful. Comments and criticisms are welcome.
Art

P.S. The sharp eyed among you will have noticed that the front emergency buffers are in place and need to come out after the car is back in the land of the living. I'd better make myself a note.

Edited by - Art Love on 08/11/2010 02:08:03
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Ron B

Australia
11612 Posts

Posted - 08/11/2010 :  05:15:31  Show Profile  Visit Ron B's Homepage  Reply with Quote
I was going to mention the buffer in place... What I do is loosely hold the valve in place with the bolts,then fit the pipes. The valve can move a bit to enable the pipe nuts to be fitted before tightening them.
Then i do the mount bolts up tight before tightening the pipe nuts.
Normally,when dealing with pipes like these, it pays to have both ends loosened to enable the pipe to fit into where ever with out any danger of cross threading etc.
But these are all too long so a lot of care is required when first removing the valve. Any excess bending will cause grief later.

quote:
12-14-2004, 11:49 PM #8
Tom Hanson
MBCA Member

What the heck, try to stuff a MB 6.9 liter V8 in it. What a machine that would be..
__________________
Tom Hanson
Orange County Section
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Chris Johnson

USA
3751 Posts

Posted - 08/11/2010 :  12:41:17  Show Profile  Reply with Quote
This job is just, simply, no fun (and a 6.3 is worse!). Art, you did everything that I could suggest to make the job possible.

To anybody contemplating this job, be prepared to muster more patience than would seem to be required. Start by leaving the valve rigidly attached to its mounting bracket and loosen the hard lines from the valve. Once all the lines are loosened a bit, then the valve mounting bolts can be loosened and removed, followed by unscrewing the lines the rest of the way. Be VERY careful to not bend any of the hard lines AT ALL when extracting them from the valve assembly.

It is the errant minor bending of these lines that can transform this job from a PITA to a serious cussing, car damaging, tool throwing, maddening impossible task. There is no guarantee that the lines haven't been slightly bent by the last person that worked in there, but if they are fully screwed in then you at least know that their current shape is workable. Personally, I always get all the lines started in by a couple of threads before even loosely starting the mounting bolts.

The best thing I can suggest to make this somewhat easier is to take the time to fully clean the grease and grime (as Art has done) from the lines and valve before doing anything else. It's hard enough to get all the lines restarted without having to also deal with the fittings sliding around in your hands.



Chris Johnson
If you aren't constantly impressed with your car, then it needs fixing.
100.012-12-000790
100.012-12-000867
www.300SE.org
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Kai McRae

Australia
390 Posts

Posted - 10/05/2010 :  21:15:09  Show Profile  Reply with Quote
Art, Chris,

In your post 08/10/2010 : 21:28:23 showing the three new airlines mounted in the bracket, what is the uppermost line?

I have just discovered two things about this line on my 6.3:

1) hose movement back and forwards in the bracket. only the upper hose moves though.
2) a hissing pin-hole leak in the fabric-covered/rubber part of my hose and I am facing the job of removal and replacement now.

Seems a strange coincidence.

Firstly, what does this airline control?
Secondly, any tips for removal of this line? No, I'm not taking the engine out...
Thirdly, if i get a new hose made up from our local place, this is not a super high pressure line is it? What pressure rating are they?

Apprecate any help

1971 6.3 - #5417 -
(LPG)
1982 230E - W123 (M102)
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Art Love

Australia
6226 Posts

Posted - 10/05/2010 :  22:00:42  Show Profile  Reply with Quote
Kai,

I've been away for a few days. I'll have a look and get back to you. The photos in this thread are of a 300SE coupe and I don't know if the line orientation is the same on the 6.3 off the top of my head. Before you spend money at a local hydraulic shop, check price and availability with Tom Hanson because there may be not much difference. The 6.3 uses 3 hoses that are the same 109 997 17 82. The only other thought I have at the moment is if one is beginning to fail, I would seriously recommend that you replace all 3. None are really high pressure. 200psi max.

Art
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