need help with 300td hydraulic suspension - Page 3 - PeachParts Mercedes-Benz Forum

Maxbumpo · #31 10-29-2007, 07:56 AM

Quote:

Originally Posted by johninva

so until 2 days i could never see the tops of my tires on the rear, i impatiently adjusted the adjustable link to have the car raise up to get the 13.5" clearance from center of wheel cap to fender lip. Then I learned that this was BAD to have the valve in the fill position to maintain a static unloaded height. So i crawled under there, undid the connection from the link to the arm and lowered the arm to netural/release position, the car barely dropped at all, still can see tops of tires for sure, its like it is all of a sudden maintaining base pressure. could some internals on the valve have been gunked up or stuck ? also i noted that where the link is adjusted to now is where it ruffly should be according to the nail through the hole on the lever into the hole on the valve body method. also also now the ride seems a little bouncy, maybe a bad accumulator or two, is there anyway to do a quick test without removing from the vehicle, i tap on one it sounds hollow, i tap on the other it sounds not hollow ?
thanks for all your help

Sounds like your control valve may be OK. Leave it in neutral position, shut off car, wait about 15 minutes or so. Open the fluid reservoir and check to see if any fluid is dripping from the filter. If you've got a steady drip-drip-drip, your base pressure valve is leaking by and you will either need to replace or rebuild. Ideally there should be no dripping at all.

Replace both accumulators; they are the wear elements in the system, serve the same function as shock absorbers, and require replacement roughly every 100k miles or so. They are easy to replace, especially if you have a lift. Cleanliness is required to avoid getting contaminants into the system.

Once you have them off and before you install the new, you can verify it's bad by inserting a dowel into the hyrdaulic fitting hole and measuring how deep until you hit the rubber diaphragm, then comparing with new.

nscarr · #32 10-30-2007, 08:12 PM

Quote:

Originally Posted by ForcedInduction

Somebody replaced yours with normal shocks. What about the pump on the engine, what did they do with it?

Avoid Mercedesource completely, they are crooks.

oops, i didn't notice your question about the pump; yes, the pump is still on--bought the car in august, so i figure it's been without fluid for over 3 months at the minimum--likely dead then, right?

maxbumpo, i would consider the restoration of the system if it weren't so expensive--right now i want to keep the rear from bumping around.

forced i--i was looking for monroe air shocks online and was wondering if you could recommend a part #, or if you could steer me into how to go shopping to fit these right?

mucho gracias -n

JimmyL · #33 10-30-2007, 08:51 PM

Quote:

Originally Posted by nscarr

maxbumpo, i would consider the restoration of the system if it weren't so expensive--right now i want to keep the rear from bumping around.

Going back with the proper SLS components is about the only way to cure that. From time to time you can find the parts used from somebody who tears down a wagon. That should be your longterm goal......

There is a wagon in the yards locally, but I never have time on half price Wednesdays to pull it all off....

kerry · #34 10-30-2007, 09:14 PM

Quote:

Originally Posted by nscarr

so i figure it's been without fluid for over 3 months at the minimum--likely dead then, right?

No. Members of the forum have driven with their pumps dry for months with no apparent damage.

nscarr · #35 11-02-2007, 04:17 PM

thanks for the input!

i've read more about options and have the following possibilities for raising my wagon's rear end:

1) restore the sls (missing struts, so will wait till i win the lottery)
2) add shims (may not add desired height)
3) replace springs with w126/w116 type (i assume rear springs)
4) monroe air shocks

i have a question about the air shock possibility--if the springs are supposed to normally hold the vehicle's weight (or most of it), will the air shocks actually raise the vehicle and support its weight for regular use? or is it too hard on the air shocks to keep it lifted for the long term?

i'll be measuring the current shock dimensions this weekend and will find out if monroe has an air shock that will fit.

picture attached that shows the sag. i will also measure the hubcap-star to wheel well distance (should be 12.5", right?) this weekend. [Edit, this is incorrect--should be top of hubcap to wheel well)

thanks again, more soon.

Measured top of hubcap to wheel well at 9" [added info]

marcz · #36 12-16-2007, 04:26 PM

Hello, great thread as I have an issue with my '83 300TD wagon. I will need to rebuild my valve assembly and I've seen those detailed instructions (thanks). What I'm missing on mine is the connecting rod. After I reattach one, I'll use the other instructions to set the correct level. Thanks to those who have posted them!

dieseldiehard · #37 12-16-2007, 09:07 PM

That arm is a hard item to find, just by itself, unless you stumble onto a wrecked wagon somewhere. Maybe a post in the Parts section would be fruitful. I'll keep my eyes open for one too
I do have a rebuild kit in case you need one

JimmyL · #38 12-17-2007, 01:22 AM

Is this what you're talking about being hard to find???

http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=21N00PKVE29402XITK&year=1984&make=MB&model=300-TDT-001&category=L&part=Suspension+Pull+Rod

dieseldiehard · #39 12-17-2007, 01:08 PM

I stand corrected! They are easily bought for about $35
they aren't easy to find in wrecking yards unless a wagon happens to show up.
Thanks, JimmL

Bio300TDTdriver · #40 12-19-2007, 12:36 AM

There is a (small, expensive) repair kit for the self-leveling valve assembly, (MB part # 000-586-00-32, about $100CAD from the dealer), which includes a new valve piston, springs, ball bearings, o-rings and copper sealing rings. Give your VIN when ordering the kit, as there are different versions of the valve even within the W123 series.

There is no rebuild kit for the 124 valve. As you can see from the picture you would need a special wrench just to open it.
http://img.eautopartscatalog.com/live/L703076796OES.JPG

mobetta · #41 12-19-2007, 09:53 AM

^ making a spanner wrench like that is fairly easy. I used a piece of scarp angle, measured the distance OC of the holes, drilled 2 1/4 hol;es in the angle, installed 1/4 20 bolts, and nutted them on. cheep way to work on stuff that average joes are supposed to call in the pro's on.

vstech · #42 12-19-2007, 10:24 AM

hard to find? YOU MEAN EVERYBODY DOSEN'T HAVE A SPARE TD IN THEIR YARD? ( I have 2 spares)

dieseldiehard · #43 12-21-2007, 08:14 PM

Quote:

Originally Posted by vstech

hard to find? YOU MEAN EVERYBODY DOSEN'T HAVE A SPARE TD IN THEIR YARD? ( I have 2 spares)

I may not have a spare TD in my yard but I've got two SLS valve KITS in my house!

(one may be spoken for)
DDH

Douglas.Sherida · #44 12-21-2007, 10:01 PM

Just gotta chime in here:

I posted a DIY several months ago on rebuilding the w123 SLS valve here:

DIY: Rebuild the self leveling suspension SLS valve on w123 300TD wagon sagging rear

And, as of today I still have 2 full sets of o-rings available for $5 each. It's not as nice as DieselDiehard's facotry rebuild kits (no piston, springs or BB), but its about $100 cheaper.

Bio300TDTdriver · #45 12-23-2007, 04:47 PM

Quote:

Originally Posted by mobetta

^ making a spanner wrench like that is fairly easy. I used a piece of scarp angle, measured the distance OC of the holes, drilled 2 1/4 hol;es in the angle, installed 1/4 20 bolts, and nutted them on. cheep way to work on stuff that average joes are supposed to call in the pro's on.

OK, that sounds do able. So has anyone re-built a 124 SLS valve?