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1989 300SE, '03 E320 Wagon
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Discussion Starter #1 (Edited)
Need some help from the experts here. I have tried everything to get the 2-3rd flare adjusted out of my transmission. Its better, but still very much present. I have also noticed some metal in the pan, and its taking longer for reverse to engage.

I am on the look out for a replacement transmission. I have the 722.118, square pan, all vacuum trans. Tell me exactly what I can replace this with. Are there more than one model with the four bolt pan?

I have numbers stamped into the trans just above the pan on the passenger side (1232703201 722118 02110384). Am I looking for these exact numbers? I have seen pictures of transmissions with the numbers cast into the trans higher up on the drivers side....do I need to find those numbers on mine also?

I just dont want to ship the wrong transmission at $150 one way!!

As always, thanks for your help!!
 

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1981 W123 300D non turbo, 1992 190E 1.8 <=> 2.0
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Need some help from the experts here. I have tried everything to get the 2-3rd flare adjusted out of my transmission. Its better, but still very much present. I have also noticed some metal in the pan, and its taking longer for reverse to engage.
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A flaring transmission problem will most probably be related to vacuum.

See this thread for help =>

http://www.benzworld.org/forums/w123-e-ce-d-cd-td/1597891-diy-w123-transmission-diagnose-adjustment-722-a.html


Here's my notes about the other stuff (that I know more about than vacuum adjustments!)

See this thread for how the 722.118 looks when taken to bits

722.118 Automatic transmission rebuild (Monster DIY) - PeachParts Mercedes ShopForum


The reverse brake band is at the front of the transmission and is adjusted at point of assembly - often set in jointing compound - and is usually stuck and not easy to adjust again.

I've posted some pictures of this adjustment bolt in the peach parts thread linked above.

Before anyone tries to adjust that pesky bolt I reckon you are better off removing the oil pan and removing the valve body and then measuring the clearance of the brake bands - that starts on post 36 - you need compressed air to do the job properly...

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I am on the look out for a replacement transmission. I have the 722.118, square pan, all vacuum trans. Tell me exactly what I can replace this with. Are there more than one model with the four bolt pan?

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There are many different 722.1 transmissions.

You can see a list of them (with other data) here

FSM + EPC data => Chassis / model / transmission / drive train information - PeachParts Mercedes ShopForum

(I need to update this data but I reckon you've got a start with what's there)

The "problem" you have is that for most 722.1 transmissions there is a throttle linkage whereas you haven't got one. So that needs to be sorted. The next "problem" is that each transmission is mated to a specific engine and a specific differential ratio. The governor in each transmission is tuned to this configuration. Easiest way to ensure that you get the shift points you need for your car is to replace the transmission with a 722.118...

...but there are two types!

There's an earlier version with a throttle linkage as well!

The buggers - eh?

See this thread for how the 722.118 looks when taken to bits

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I have numbers stamped into the trans just above the pan on the passenger side (123270321 722118 02110384). Am I looking for these exact numbers? I have seen pictures of transmissions with the numbers cast into the trans higher up on the drivers side....do I need to find those numbers on mine also?

I just dont want to ship the wrong transmission at $150 one way!!

As always, thanks for your help!!
The number that matters is this one

123270321 - but I think there's a number missing - so check again

722118 is the same as 722.118 but I guess you figured that

02110384 should be a unique serial number for your transmission




All in all I'd say fix what you've got unless it has gone bang. It sounds like a simple vacuum problem - even though simple and vacuum shouldn't really be used in the same sentance.
 

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1981 W123 300D non turbo, 1992 190E 1.8 <=> 2.0
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Oh and I forgot to say =>

1) The metal in the oil pan will almost certainly be from the splined shafts that wear when a harsh shifting 722.1 transmission is left to fend for itself. See the peach parts thread for more information on that.

2) Most people seem to think that an upgrade to a 722.3 transmission is a smarter move - but again you've got the differential ratio / governor problem to sort out.
 

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1989 300SE, '03 E320 Wagon
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Discussion Starter #4
Army, thank you for the info. I have hours of reading with all of this. I really want to learn more about these cars. I probably will never get to the point of doing a transmission rebuild, but I am going to pour over all this info.

You were correct, I was missing a number in the first group it is :

1232703201 I was missing the last '0' before the '1'.

I have had a new development overnight. My wife drove it a couple miles to the store and back and told mee it was 'slipping' in the last gears. I hoped in and sure enough, it now flares on 2-3 and then really slips at 3rd and 4th. I checked all vacuum which is good. Checked VCV which seemed good with no luck. I even put a spare VCV on to see if it would make a difference but it did not.

Looks like I might have to step up my search!

Again Army, my hat is off to you sir, thank you again!
 

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1981 W123 300D non turbo, 1992 190E 1.8 <=> 2.0
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...
I have had a new development overnight. My wife drove it a couple miles to the store and back and told mee it was 'slipping' in the last gears. I hoped in and sure enough, it now flares on 2-3 and then really slips at 3rd and 4th . I checked all vacuum which is good. Checked VCV which seemed good with no luck. I even put a spare VCV on to see if it would make a difference but it did not.
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OK hold up!

Slipping != flaring

Have a look at the "relationships" table on the first page of the monster DIY thread on peach parts. I'll link in the picture here - and perhaps it will stay there for a while - but I think BW kills links to other servers after a while - so if it isn't here anymore go to the source.



Gears slipping in 3rd and 4th indicates a problem with the K1 clutch.

On the basis of having taken two 722.118s to bits before I'd hazard a guess that the problem probably won't be the clutch surfaces themselves unless the transmission has done stellar mileages - I know that statistically speaking I should have taken 3 transmissions to bits to say this with confidence! But I'd have a look the valve body springs first - see that thread again for their positions - I think they are there (I'm being a bit lazy I haven't checked - so if you can't find them drop me a line)!



Please note - the information you've given of it slipping in both 3rd and 4th is important. If it only slips in 1,2 and 3 and has problems going into 4th say then my diagnosis would be B2 piston. Different bit - see the relationships table I talked about.


B2 piston is a common problem - a much more common problem - a much more likely to happen problem.


Be careful when you describe your observations and make sure you send the correct information - it will save you going off on a wild goose chase. I can advise (a bit) but I'm not doing the job. You are the real grown up here! You choose what you do to the car and I'm sorry to say that that makes you responsible. I say this because diagnosing transmission problems can be difficult. I don't want you to be disapointed.
 

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1989 300SE, '03 E320 Wagon
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Discussion Starter #6
I will have time tomorrow after work to drive it again and I will report back exactly what gears are doing what. I described 'slipping' instead of 'flaring' because it never flet like these gears shifted all the way, or 'locked in'. When in 3rd and 4th and driving normally it would maintain speed, but any touch to the skinny pedal it would rev, like slipping.
 

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2001 Volvo V40
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I checked all vacuum which is good. Checked VCV which seemed good with no luck. I even put a spare VCV on to see if it would make a difference but it did not.
How exactly did you check the vacuum? Can you describe it in a bit more detail?
 

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Discussion Starter #8
Ok test drive after work:

1 - it seems to be starting off in 2nd, not 1st like normal.

2 - next shift 2nd to 3rd seems to never complete. Trans slips and car is basically undriveable. I can manually put car back in first

3 - when I drove the other night I was able to get 4th, but any decent touch to the throttle and it would slip (engine turning higher RPMs without increasing any speed)

Today I tested vacuum again. I used my MightyVac and a vacuum guage.
Those results:

22 Hg at main T going to 3/2 and VCV
22 Hg into 3/2 switch
0 Hg out of 3/2 to VCV. Zero idle- Increases as throttle increases
22 Hg going to modulator, drops as throttle increases

Used MightyVac to test modulator, can pump to 20Hg and hold

Hope this helps, any other thing you want me to test, just let me know

THANKS AGAIN GUYS!!!
 

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Here is the vacuum scheme for the USA 300D.



At idle the full vacuum of the pump (22" Hg) is at nr. 62. It also connects to the underside of the 3/2 valve. At idle that valve is closed, so full vacuum is at the modulator and the EGR (C in the scheme). When you press the accelerator pedal, you actuate the 3/2 valve, so a connection is made with the VCV (nr. 65). Now the full vacuum is reduced by the VCV. If you measure at the red dot (remove line to the transmission and connect a gauge, or connect gauge with a threeway connector), you can measure the vacuum that is going to the transmission modulator (nr. 19). That should be 22" Hg at idle, than drop instantly to 10" Hg once the 3/2 valve is actuated. Vacuum should further reduce linearly to 0 at full load. If you disconnect the rod of the VCV you can simulate the full load condition without revving the engine, but the 3/2 valve must remain actuated.

It sounds like the vacuum is more or less working, but the amount of vacuum is crucial, as this is a vacuum-only transmission. The slippage in 2>3 and not starting in 1st gear can be a sign of the wrong vacuum signal. If the VCV isn't working properly, and that is not uncommon, the transmission will act normally.
 

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Discussion Starter #10
Ok I have been trying to post the 617.912 vacuum diagram and color coordinate to show what vacuum I have where, but Photobucket is not working for me.

I just tested vacuum as you suggested (red dot) and I do get 22Hg at idle, but it drops right off to 4Hg as soon as the 3/2 is activated, and to zero with more throttle
 

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That is not OK, although with such low vacuum, I would expect a hard and late shift, not slipping shifts.

The VCV needs to be cleaned and adjusted.
 

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Discussion Starter #12
Ok, I will tackle this next, I would love a harsh shift at this point....any shift!!
 

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Discussion Starter #13 (Edited)
I now have the VCV adjusted to when 3/2 activates, vacuum drops to between 9Hg-10Hg , and decreases as throttle is applied. I still have the same results. At this point it will not shift into third or fourth gear.
 

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The vacuum control is eliminated as a possible cause.

It could be a broken pin of the vacuum modulator (the pin is plastic) or other internal damage to the transmission (of which the metal shavings are an indication).
 

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Discussion Starter #15
I have a brand new modulator. I bought it months ago, but ended up replacing only the O-ring. I will try the new modulator as a last ditch effort! Does the modulator just unscrew? I have replaced a few on old American vehicles over the years.....

Again guys thanks for the help!!
 

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Does the new modulator have a pin? It is a seperate part which needs to be glued into the modulator. If the modulator holds vacuum, the modulator is OK.

The modulator unscrews alright, but oil will flow from the hole.
 

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Discussion Starter #17
It is the green style modulator. The pin(adjustment pin) is metal, looks like a simple key. Well then if it holds vacuum its ok, then mine is fine. I can put 20 Hg on it and it will hold. Looks like Im transmission shopping. :(

Not a huge surprize, I have kind of thought in the back of my mind with this 2-3 flare I was unable to adjust out that I had trouble coming.

I have my 124 gasser wagon to drive until I find a tranny....I just dont like driving it as much as my 123....she's my baby
 

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The pin is on the inside, the vacuum controls the movement of the pin. In the picture below it is not there, but it goes in the middle of the threaded end. Are you sure green is the correct colour? I will take a look in the German FSM if that is the correct colour.

 

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Discussion Starter #19
I was WRONG, mine is red. I am at work and dont have my hands on it, I was thinking green for some reason. This is my exact modulator. By 'pin' do you mean the metal thing that looks like a key? I have adjusted that pin to try to get some improvement.....counterclockwise turns

 

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Nope, it is the pin which is on the inside of the transmission, connected to the modulator. Once you remove the modulator, you'll see what I mean. Below you see a picture of the pin of a slightly newer modulator.

What you describe is the adjustment screw.
 

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