87 300TD will not shift out of first - PeachParts Mercedes-Benz Forum

old goat · #1 03-18-2010, 04:55 PM

I posted a thread a while back about the vacuum modulator on my son's car going bad. I have replaced the modulator and the vacuum measurement is perfect. The tranny's fluid level is right up to snuff but it will not shift out of first.

For history, the car has over 260K on it and the trans was replaced with a rebuilt unit via Adsit. The shop that did it, an old Mercedes mechanic, always used Adsit. Anyway, the trans worked perfectly for maybe 5K miles and on a trip of 225 miles, at about 200, the tranny started having issues with shifting. It was driven the last 25 miles on 2 lane roads shifting difficulty from 1st to 2nd to 3rd and finally 1st to 2nd only. Towed the car home and went through tests and discovered the vacuum issue. Replaced the modulator valve but can not get it to shift. Bowman cable appears free and working. Does anyway one have suggestions as I am now totally clueless as to what is going on??

Thanks, Frank

compress ignite · #2 03-18-2010, 05:02 PM

Adsitco (Nothing Good can Ever come of them taking your money)

http://www.peachparts.com/shopforum/showthread.php?t=233610&highlight=adsitco

Look underneath the Accelerator pedal...Is there an Electric "KickDown Switch"?
Unplug it and see if the Upshifting problem goes away.(BAD Kickdown switch)

Picture of the little bugger below (Less than $20 part)

If that's not the problem...Any chance the Box is still in warranty?

old goat · #3 03-19-2010, 09:14 AM

Thanks for the input. I had forgotten about that switch. I am not holding out hope at the moment but will keep the fingers crossed.

As for Adsit, I would not have taken it from them. This is my son's car that good old dad is trying to repair. The trans was replaced in Albany NY area and apparently the guy had dealt with them for years. Yes, it is still under warranty BUT as the Peachtree site says, I have to get another one....plus pull and replace the trans. Know anyone that would like a really good condition wagon that needs a trans....I will sell it cheap!!

Thanks, Frank

compress ignite · #4 03-19-2010, 02:14 PM

Brother,

Put it in the Cars section,if you really want it gone.
The Wagonistas are a really rabid subset of Mercedes owners.
(Some of them mount spare Hoods on the outside of their garage doors)

The nice thing about the W124 Wagons is they're mostly pickup truck,too.

[Thanks, RRGrassi . I was looking @ vehicles in his signature]

Check and see if Adsitco's warranty covers R+R under warranty (It Should)
(And Lawyers always tell the truth,Too)

This member has the Transmission bugaloo down...Stevebfl ,Continental Imports
(Independent MB shop in Gainsville,Fl)

http://www.peachparts.com/Wikka/TransVacTune

I would PM him after you'd tried everything else.Before you unload it.

Here's a Mitchell's on the 722 series tranny somebody found in Russia:
http://w126.pp.ru/akp722.pdf

GSXR posted this:

http://www.w124performance.com/docs/mb/other/tranny_722_repair.pdf

And this be Roy's everything including the Kitchen sink:
http://www.peachparts.com/shopforum/showthread.php?t=142395

rrgrassi · #5 03-19-2010, 02:18 PM

I think this is a w124 wagon. If I was not in Texas, I would snap it up!

old goat · #6 03-19-2010, 04:07 PM

Thanks for the various links. Some I already had and some I need to go through. Maybe several reads will bring a "that's it!" out of all of it. I have tried a few of these but so far I am flummoxed as to what is going on. I just may have to give Roy a call as well.

To RRGrassi....hey, Texas is not that far....and yes it is a wagon. I flew down to Houston to pick up the 86 300SDL!!

Anyway, if I find no reasonable solution, I may just sell it.

Adsit pay the shipping??? I am not holding my breath!

Thanks, Frank

mplafleur · #7 03-19-2010, 10:14 PM

If it's not the kickdown switch, it may be the kickdown solenoid in the transmission body. It is located somewhere near the back of the tranny. Mine was stuck once when I first got the SDL running. It was like it only had first gear and wouldn't shift into second. I had to stomp on the kickdown switch a few times before the solenoid unstuck.

Haven't had a problem with it since.

vstech · #8 03-19-2010, 10:30 PM

I wish you much luck with the transmission. if you do decide to dump the car cheap, I am a little closer than texas... I've driven to chicago for a car before...

old goat · #9 03-20-2010, 12:01 PM

Thanks Michael....fabulous suggestion as that is exactly what I did and the unit is shifting once again. It has some "clunk" to it but I have not checked the trans pressure yet but shall do so soon. I will also double check the vacuum levels again.

Thanks for all the suggestions and input. And my apologies to anyone thinking they could buy this car cheap. Except for one year, it spent its life in the south and was purchased from the original owner who took very good care of it. There is not even a crack in the dash!

Frank

vstech · #10 03-20-2010, 12:25 PM

Sweet! there are a ton of threads here on clunk shifting adjustment. try that "critical adjustment of vacuum" thread... perhaps someone here will post the FSM info on your transmission.

biopete · #11 03-20-2010, 01:21 PM

Quote:

Originally Posted by vstech

Sweet! there are a ton of threads here on clunk shifting adjustment. try that "critical adjustment of vacuum" thread... perhaps someone here will post the FSM info on your transmission.

I have the W124 FSMs. Would gladly post -- but where is it in there. I can find nothing on transmission.

Thanks

compress ignite · #12 03-20-2010, 03:06 PM

Ici:

http://www.ps2cho.net/downloads/MB%20CD/W124/Index/Groups/27Transmission.htm

and the adjustment subset:

http://www.ps2cho.net/downloads/MB%20CD/W124/Index/Resources/27-110trans_Bowden_adjustment.pdf

ANNNNNNND Stevebfl's tutorial:

http://www.peachparts.com/Wikka/TransVacTune

SMR's "Critical" Tranny post:

http://www.peachparts.com/shopforum/showthread.php?t=158216

My Version of THE Forum must be the Alternate Universe Model,It has
Two particular sections that No One else has:

SEARCH button
and
RESOURCES Link

EDIT:
REPOST

old goat · #13 03-21-2010, 10:17 AM

Does anyone know what the specified pressure is for a 722.317 transmission should be??? I can not seem to find that number anywhere.

Thanks, Frank

Mazootpusher · #14 03-21-2010, 11:23 AM

If you are asking for the "Modulator Pressure" for 722.317 is 46 psi.

Line Pressure 75-90 PSI in Drive @ Idle160-195 PSI @ Stall in Drive
Governor Pressure: 1/2-2/3 of Road Speed Example @30MPH Governor Pressure Should be Approx. 15-20 PSI.

old goat · #15 03-21-2010, 12:11 PM

Thanks a lot!! Just the information I needed.

Frank