what are symptoms of b2 piston failure
 

my 87 sdl with 164k will not shift out of first or is itreally second,i can put it into neutral and then bcak to drive to get it to go to 3rd and it also can have difficulty going to 4th.this has happened before,fluid was changed in the last year.do i need to get a rebuild?current problem just began,before that it had been running well,no leaks in trans.i have looked at diy linkd about b2 piston,but am not sure that is my problem.

pretty much NO first gear. Reverse will be fine. If you can rev the motor and get it into 2nd to move you should be able to drive at speed. I bought my beater with a broken B2 and didn't have a clue. But thats all it was. Good luck. Thanks

i have a gear to begin driving but it wont shift to the next gear without putting into neutral and then back to gear,this is also happening on 3-4 shifts.im thinking this is not sounding like b2 psiton symptoms.reverse is fine.i am really hoping not to need a rebuilt.

not a B2 problem
 

As you noted, something "broke" on your car, it DOES NOT NEED a bunch of random adjustments.

A B2 failure (bad seal, broken piston, etc) has NO first gear. If reverse works, your pump, filter, etc are likely good. Check the fluid level. Then check the bowden cable that connects the the pedal linkage and goes down to the tranny.

Grab two flat screwdrivers and a pair of pliers. Stand at the left front tire. The attached picture shows the inspection area. The green circle is the adjuster--leave it alone. The red circle shows the accordion bellows around the cable; inside it is a small "pull" cable like a bicycle shifter or brake. Use the two screwdrivers to pry the ball (blue circle) off its connection. Grab the ball end of the cable and pull it out (total travel about 1.5 inches 40 mm) with your fingers. It should be "springy" and pull itself back in as you release it. To reassemble, just pop the ball back on by positioning it over the mating ball and lightly pinch with the pliers.

If nothing seems awry with this system, you might check the kickdown switch (under the "gas" pedal, unplug it) and solenoid (right rear of transmission case).

Start with the easy stiuff first. It doesn't sound like a B2 at all. Next is the vacuum on bowden cable. If it has the gears then I wouldn't think rebuild I would think what shifts it. When did it and how did it start???Thanks

Honestly it sounds like your fluid is miserably low - symptoms are consistent with very low fluid level. Check that first before anything.

this began a few days ago when i manually shifted down to second going up a hill,after that it began having difficulty getting out of ist,and also at 3-4 shift.i have other cars to drive and tried to see if a day mad a difference and it has not.before this it was shifting well.

ill check fluid tonite as well- i agree startwith simple things,would a bowden cable misadjustment make it really difficult to get out of ist?

i checked fluid when i got home ,it was ok.imstarting to think i need to change out trans. 87sdl doesnt have a bowden cable does it?

Dude I thought we talked. Simple things first, but if you want to swap it out go for it. Thanks

WTF? Why did I spend twenty minutes today taking pics of my 1987 300SDL and writing a diagnostic description???:mad:;:confused:

Waste someone else's time tomorrow.

take it easy a little patience ,boise benz your images were not attached (please attach again)to your comments,i will go out per your written description and check.dont give up on me yet.

okay bowden cable doesnt seem to have much spring to it,what do i do in this case.?im used to bowden on my 300d completely different

little Bowden effect?
 

Now we need a "WTF?" to the operator of this computer and the interwebs for not posting the picture yesterday. You've already discovered the Bowden stuff, but here's the pic anyway.

I just disconnected my cable and drove around. It had little effect except for removing any kickdown (except floored, which is the electrical pedal switch and trans solenoid). It ran right through the gears 1-2-3-4, though the shift points and firmness were somewhat different. The 0.5"-of-throttle 1-2 shift was at about 7 MPH.

Now what, folks?

With the cable disconnected, it will shift early. With the cable seized or otherwise held in the open-throttle (extended) position it will start in first gear and shift late as if you were driving with full-throttle.

I'm currently dealing with the same issue in one of my cars; starts in second and doesn't upshift to 4th, ... I'm thinking either throttle-body or hydraulic pressure in my case. If you're starting in second you might be in the same boat and the next step is to test pressures. If you're starting in first and shifting late/won't upshift it can be the bowden cable is not returning, the downshift switch is stuck (un-plug to test), or the downshift solenoid is leaking/stuck open.