B2 Piston W124

[lino]

I am finally ready to deal with the B2 Piston problem with my W124.

Here is some information about my car:

Vehicle: 1989 300CE
Engine: 103.983
Chassis: 124.050
Transmission: 722.358 (4speed / 6 Bolt / Large Case)

According to the link below:
http://transmission.articles.mbz.org/b2/

I will need the following parts (Prices in Canadian Dollars):

107 270 04 32 ___B2 Piston $163.50
005 997 70 48 ___B2 Piston Seal Ring (to the cover) $5.20
126 277 08 50 ___Plastic Bushing for Updated B2 Piston $5.63
006 997 73 47 ___Seal that holds in the bushing $5.15
126 270 44 77 ___K1 Spring Kit NO PICTURE - $15.22
126 277 25 55 ___Seal - Not sure if I will need this one PART # CHANGE – 140 277 03 55 $8.00
126 271 11 80 ___Transmission Oil Pan Gasket $13.78
126 277 02 95 ___Transmission Filter Kit $33.30
xxx xxx xx xx ____Transmission Fluid REGULAR ATF
xxx xxx xx xx ____3 New Front Crossmember Bolts





Questions:

1. Does anyone here have experience with a B2 Piston repair on a W124 and were you able to do it with the transmission still on the car?

2. Does anyone have any suggestions or comments about the parts list I am about to order? Am I missing any parts?

Thank You

[nglitz]

There's this

best of luck,

[lino]

Thanks Norm. I already had that link from before and it is a good one.

Today's update:
I went to 3 Mercedes dealers and spoke with their top mechanics and 2 of them said that I will need the B2 band and 1 said it is the B2 Piston. This is without looking at the car just by my description of the problem I am experiencing. The B2 band requires the removal of the transmission and taking it apart (6 hours to remove and reinstall). Replacing the B2 Piston according to the 3 people I spoke with can be performed while the transmission is still on the car (2 hours). So I ordered the following parts today:

107 270 04 32 ___B2 Piston $163.50
005 997 70 48 ___B2 Piston Seal Ring (to the cover) $5.20
126 277 08 50 ___Plastic Bushing for Updated B2 Piston $5.63
006 997 73 47 ___Seal that holds in the bushing $5.15
126 270 44 77 ___K1 Spring Kit $15.22
126 277 25 55 ___Seal - Not sure if I will need this one PART # CHANGE – 140 277 03 55 $8.00
126 271 11 80 ___Transmission Oil Pan Gasket $13.78
126 277 02 95 ___Transmission Filter Kit $33.30


According to the link below:
http://transmission.articles.mbz.org/b2/

It is recommended to buy 3 New Front Crossmember Bolts. Will someone please call Rusty at 1-800-741-5252 and ask him what the part numbers are. The car is a 1989 300ce. That telephone number doesn't work for me.

Thank You

[C32AMG]

The problem is not removing the B2 piston; it’s removing the piston seal and bushing. Those tutorials do not tell you how to do that.

[lino]

Originally Posted by C32AMG

The problem is not removing the B2 piston; it’s removing the piston seal and bushing. Those tutorials do not tell you how to do that.

How hard is it to replace the piston seal and bushing?

[C32AMG]

.
It is very heard to remove them thru the piston bore, from the out side. The space is limited, even if you made a hook type puller the B2 band would be in the way.
The easiest method that I found is to remove the valve body and plate, Then remove the B2 band guide by pulling it out of the case, once removed you will have greater assess to the B2 piston seal and bushing. With a brass drift punch, tap the original aluminum bushing and seal out of the case. If you are lucky the seal and bushing will pop out if not then from the piston side crush the seal in, too loosing it then tap the bushing until it comes out. Caution: the B2 seal and updated plastic bush gets installed from the out side of the case, thru the piston bore. Before you start make sure you have adequate clearance. I would post some pictures but they are not up on my web site yet.

[pwogaman]

Nice thread!

[ps2cho]

I can recommend sun valley mercedes for rebuilt transmissions. They rebuilt my 722.3 and its been running like a dream. Got 3k on her so far.

[JamesDean]

Hey everyone,

I just came across this thread in a search for (what I believe to be) my 300D's B2 piston failure.

Yesterday I changed the engine oil and a coil spring. After the oil change I drove the car around the block and all was good. Normal shifting and everything.

Today I went to get some food and bam, only first gear.

Its good to know that getting to the B2 is not as impossible as I thought. Maybe it was the 123 that its rather hard to access...

[tbomachines]

Originally Posted by JamesDean

Hey everyone,

I just came across this thread in a search for (what I believe to be) my 300D's B2 piston failure.

Yesterday I changed the engine oil and a coil spring. After the oil change I drove the car around the block and all was good. Normal shifting and everything.

Today I went to get some food and bam, only first gear.

Its good to know that getting to the B2 is not as impossible as I thought. Maybe it was the 123 that its rather hard to access...

B2 would be no forward gears at all, like if you were in neutral.

[JamesDean]

Originally Posted by tbomachines

B2 would be no forward gears at all, like if you were in neutral.

Its kinda like that up until you get to 3-4k rpms. Then it'll start to pull.

VERY similar to what happened with my 300SD a few years ago.

[pwogaman]

Did you ever get a final diagnosis?