Wee,

It could be your B2 piston, and B1 piston acting up. The cause maybe leaky/worn o-rings around the piston(s), or the B2 piston it self.

b2piston

Step by step process:

How to Replace Your Oil Cooler Lines

Before you go nuts on the B2 and B1. Check your Fluid level, and replace/inspect that filter.

One more thing, the modulator has a mechanical cable attached to the throttle somewhere near the throttle body. Take a look to see if it did not disconnect it self. On my car it has a ball joint-disconnect it and see if if the inner cable slides in and out(about an inch or so). It should move. Meaning the modulator is not stuck...

Take a look at this link and download the master.pdf document(which is a service manual for your transmission and others) contains a trouble-shooting section in the beginning of the document-See post 26:

http://www.benzworld.org/forums/w140-s-class/1407863-no-reverse-jerks-reverse-when-cold.html



The modulator seems easy as it is on the outside of the transmission, but a pain to disconnect from the transmission line.

One last thing, their are two vacuum lines going into the transmission make sure they are not cracked or disconnected. These could be goofing you up too.

Best of luck,

Martin

 

Where are these vacuum lines? i have a 97 s500 w/167k on the clock. the other day it went into limp mode (no signs of pending problems) attached pocket scanner and it popped the codes po715 & po720 (input & output speed sensors) thru some articles on this forum the issues is stated to be a bad conductor plate (sits inside trans on top of valve body) so i got the new conductor plate etc, and follow a detailed step by step how to posted by G-AMG, i just got done doing the entire job myself in my driveway, attached scanner again to clear codes, add new trans fluid and go for a test drive, however problem still exists. maybe its a vacuum line? but where? any direction would be greatly appreciated.

 

BigBenz,

The beauty of the 722.6xx is their are no vacuum lines, and intermediate bands(brake bands) or brake band pistons to deal with. The 722.6xx is easy for the DIY mechanic to rebuild. Only takes 1/3 of the time to rebuild compared to the other W140 transmissions, but with one exception that "Car Soft"(or MB star is need to reset the codes. OBDII will not clear the codes.

Now, I heard their is a process which uses the ignition in combination with the gas pedal, but I cannot confirm that for you if it works or not.

I think for you. You have three options:

1) Have the dealer reset the DTC codes

2) Have the indie Mercedes repair shop repair shop do it too

3) Buy one of these car soft reset tools, but I believe you get it at sears(order it from them). if your interested, I think I have a link some where on this; I think if you search here on the forum using sears. You'll run into the thread on car soft.

Hope this helps,

Martin

 

Martin: thanx for the reply, i will try the fix again in the morning using the ignition & the gas pedal. you turn the key to position 2, mash the gas pedal to the floor and hold for 5 seconds, the release the gas pedal and turn the ignition to the 0/off position. do not remove key, dont open any doors dont breathe or move an inch for 2 minutes, this will allegedly reset the trans. if not i may limp it to my nearest mb stealership or indie mb mechanic. i will search for the 'car soft' reset tools from sears. thanx again.

 

The 92 600 has a 722.362 trans with no electronics and a vacuum modulator. the 722 trans has a history of front clutches

 

BigBenz,

You are welcome

Since I have a W210 wagon with 722.6, I remember one person had this same issue, but this person found it the device at sears of all places. Here is the link:

http://www.benzworld.org/forums/w210-e-class/1630155-722-6-trans-issues.html

I hope this helps you,

Martin

 

More...

 

...and a few more...

 

Wee,

I understand your concern about your knowledge, but you must start somewhere, and empower it. Do your research, and find a independent repair place that can repair a transmission at component level instead of a full repair but...

I am assisting with being an "Arm Chair Mechanic" here as nothing can prepare you for what you actually encounter that you will encounter. As a transmission has many parts, and one can give multiple symptoms. I have one of my W140 transmission in a million pieces right now in my home. I too have the same early symptoms except mine ocured about every month or so. What I discovered was I had a combination of the B2 piston being worn out(my fluid was always dark gray every year I changed the fluid and filter-B2 was the culprit) B2 shaft oring was worn as the result of overheating, but my clutch packs for gears two and three were worn too.

Not trying to scare you here, but these cars are old, and nearly all automatic transmissions will have catastrophic problems between 100k-200k miles; Those that last beyond that have been thoroughly cared for, and/or come from cooler climates.

About this cable, see the link below, and look at the forth picture.Disconnect the cable from the throttle body see if it actuates (the head of it)about an inch, it should feel springy too. This cable is called the "bowden cable" it goes to the modulator(it is yellow plastic device, but the top of it may be black,white or green) on the out side of the transmission on the passenger side. In between the modulator are the B1 and B2 piston covers.

Get the right dip stick is the first thing..You need a point of reference order it from Mercedes or find one at the junk yard. It needs to be for your 600SEL, and I think you have a 722.3xx transmission, but make sure on this!!

The fragment of the dipstick "can" cause you problems. Block the filter, maybe collapse the filter which could starve the main oil pump in the transmission.

1)I would drain the fluid into new large paint pail
2)pull the pan
3)pull the filter
4) inspect the filter and pan for debris

With your new dipstick add new fluid(I think its four to five liters of fluid)

http://www.benzworld.org/forums/w140-s-class/1368666-transmission-removal-m104_s320.html

About the slow leak, where is it from? Perhaps from the B1 and B2 plates on the passenger side of the transmission?

I hope this helps,

Martin

 

I'll check the cable thingy.

I called the fluids place and they said they'll look at it tomorrow (fluid level/condition). I'm fairly sure the dipstick/tool I have is doing its job okay. I just need a pair of pliers to get it out of the tube.

I've read the tutorial you showed me earlier on a few times over. Seeing as how the fluid is only a couple of weeks old, would I be able to drain the fluid into a very clean container, check the bottom of the pan, check the filter, and then put the same fluid back in (maybe this is a stupid question)? The way I see it, as long as it remains clean, the same fluid being put back in after partially draining it would be no different than not draining the fluid at all. The difference is that I would know what the filter looks like.

As for the leak...I'm not sure. From what I saw, the part of the transmission showing when you go under the car was pretty brown, and also the bottom of the pan (which covers the b1 and b2 pistons) was also covered in fluid (see previously attached pictures). I've had the car for about 3 weeks now and I see about 10-15 drops of what seems to be transmission fluid on the ground where I park the car.

I'm worried, but mainly upset because I have to drive my car lightly in order for it be okay. I don't gun it every single light, but not being able to do it ever is annoying. It doesn't help that transmission fluid ranges from $15 to $30 per liter! And she takes 7.7 liters!

 

Oh and as for the fluid itself...I didn't check it properly last night, but today I'm going to check it properly (as I understand, run the car for 1-2 minutes on idle, drive around for 5-10 minutes, pull over, check the fluid while the engine is running), and I will also report the smell and color. I'm not sure what it's supposed to smell like, but it wasn't pleasant I know that. Not sure if it was burnt? Can't wait for the day we can send smells through the internet!

 

Wee,

The second to the last picture-the one with the orange rubber. Disconnect from the ball joint on the right of it, and test the spring action to see

About your oil, you do not have to buy fancy Mercedes oil as it recommends in the manual to Dexron II, but Dexron II is not available DexronIII is everywhere, and it is about 12usd for a gallon(about 3.7 liters per gallon) here in the US You can even find it at walmart.

Get a new dipstick when you can, I replace the dipsticks on all my cars when i acquired them.

I'll send you picture of the modulator with the B1 and B2, so you know what it looks like.

Martin

 

I think I have an idea of what the pistons you were talking about look like. Unfortunately, transmission oil is not that cheap here in Canada. Chepest DexIII fluid is 5 bucks per liter, 4 liters is 30 bucks, 20 liters is $55.

So if I do decide to drain the pan and inspect the filter and use NEW fluid, should I drain the torque converter as well? Or shall I just replace the volume that was drained from the pan only? Probably depends on the condition, right? Maybe I'll just drain the whole thing myself and change the filter...or maybe wait till tomorrow when I go to the lube place (I can get a top up there, but they will not replace the filter for me unless I provide a filter, gasket, and pay for the fluid).

Going out now to look at the fluid level and condition. Should not smell burnt and should be pinkish, if I'm not mistaken.

 

The fluid should be still reddish. You could strain the fluid with a "woman's panty hose"-ask the wife or girlfriend for a torn pair. If you have to buy some, get some with a sheer number around 20-30. I do hope you did buy Mercedes spec fluid for 722.9xx transmission as Mercedes will say it is compatible with the older Transmissions.

Martin

 

Martin,

Fluid is pink and reservoir was full. Did not smell burnt. I've sent you a PM with a video with some more information. I looked at the bowden and fiddled with it. If you could watch the video (about 2 minutes), and let me know if I didn't break anything, I would really appreciate it. I have not started the car or put it into gear so I can undo what I did. I remember the condition it was in before I changed it.

Thanks again.

 

Wee,

What you did is okay, but that adjustment will play a role on where the transmission shift points are. What I wanted to find out if when you disconnect the ball joint at the end of the Bowden cable from the throttle was springy? It should have a travel of an inch or so(the cable it self!).

Next, The vacuum lines should be connected too.

Martin

 

Sorry, I have no idea what the vacuum lines look like to be honest...look for them going into the transmission?

Also, I don't know how to disconnect the ball joint, it seemed pretty..stuck. But I can remove the whole piece and see if the cable moves. I will do that right now.

 

The ball head pops off with a flat screw driver-use two if you need to..Pry it from the bottom.

Send me your VIN, so I see where they are located on your transmission.

Martin

 

PM sent. So adjusting/reconnecting the cable on the throttle body fixed the first gear shift. She shifts from 1st to 2nd perfectly, but 2nd to 3rd is still strange (shifts at the correct rpm, but revs very high and then engages next gear). 3rd to 4th seems okay, but not as good as 1st to 2nd.

Let me know about the vacuum tubes.

 

Here is what I found EPC

Wee,

Here is what I found on EPC with the VIN:

Martin

 

I guess I spoke too soon; the cable I tweaked only made 1st to 2nd shifting better when the car wasn't in limp mode. But now, she goes into limp mode almost every time I drive her!

I'll look at the documents you provided. Thanks Martin.

As for changing the filter, the lube place I go to says if I find the filter and gasket, they'll charge 40 bucks to replace it and they'll use their own fluid (i.e., they won't charge me for fluid I guess). The filter/gasket kit will cost me $30-40. I'm not sure if I should just buy the kit and fluid myself and do it. Fluid will be $40 for 8 L of DexIII generic Canadian Tire brand ATF, or $55 for the same but 20L.

He said there was enough fluid, but it smells bad/burnt. I guess my idea of what it was supposed to smell like was incorrect. He also suggested that I use Lucas tranny fluid conditioner after the filter and new fluid is put in, even after mentioning that people [on these forums] generally suggest not using any of those cleaners, as they will make the problem worse.

I guess I'll have to get a new filter eventually. Which route should I take?

 

Yea, I'm against "Mechanics in a bottle" they do more damage in the end.

Take a sample from the dipstick, and smell it; Then smell a new bottle of transmission fluid. They should smell the same since you changed the fluid several months ago, or did the outfit that changed your fluid changed your fluid?

Martin

 

What do you mean "or did the outfit that changed your fluid changed your fluid?" It usually shifts out of 1st okay but will continue to slip and disengage from the crankshaft (i.e., go into neutral) occasionally. Then when that happens, I think it goes into limp mode, and to get out of limp mode, I just need to drive at normal speeds, then shift down into 2nd gear manually, the car jerks back a bit and revs higher, then put it back into D, and then it uses all 4 gears again. Shifting from 2nd to 3rd is still rough.

Anyways, I guess I need to get the filter changed, right? I'm willing to bet that won't solve my problem...what happens when I change the filter and fluid, and have the exact same problems a week later?

 

Wee,

Like others will say when people say "has the fluid and filter been changed", and can you qualify that-people for get-they might have forgotten to change the filter, or you those quick lube places that force-out the old fluid, and never change the filter.

Now, the figure of speech when one says "transmission fluid change" the assumption goes that the filter is changed too. Do not go to locations that that do not change the filter if you DIY-it, always change the filter.

If you do change the filter, get your old filter, and dissect it for particles or sludge. This may show your current problems, or show the future you may have with it.

Look at these video for 722.3 and 722.6 for the disassemble of the filter.

FixEuro.com - European Transmission Specialists - Our YouTube Channel

Martin

 

In addition to all these also check vacuum modulator valve on the driver's side of the transmission. Disconnect it's vacuum line from the manifold and check if it holds vacuum. If it is original from 1992 it will fail. You need to replace it and it may improve your shifting.
And in case you did not know - your transmission starts in second gear unless you floor the throttle or manually shift to first. Also, it doesn't have "limp home mode".

 

I'll do my best to check the vacuum lines but I'm not entirely sure about what I'm looking at. Yes I am aware of the car always starting in 2nd gear unless I either floor it, put it into B and then go back to D, or the cats are still warming up. Didn't know it doesn't have a limp mode, but all I do know for sure is that often times, it will not shift out of 2nd gear, and if I go half throttle, it downshifts to 1st gear and always goes back to 2nd gear at a very high rpm. The only way to get rid of this is to shift down to 2nd manually whilst driving, then the car jerks back and forth a bit and acts funny, then put it back into D, and it works fine again.

I will have the filter changed soon, and I will report back then.

 

wee,

This may work for you too.

http://www.benzworld.org/forums/w201-190-class/1361737-diy-mercedes-722-3-722-4-a.html

Martin