Calling all auto tranny gurus - look what I found in my pan - PeachParts Mercedes-Benz Forum

Flounder · #1 02-08-2009, 01:43 PM

I dropped my tranny pan today to change the fluid and filter, and look what was laying in the pan:

I understand it's a broken piston from reading some of the info on this site, but which one? B2? Also, after I filled the tranny back up with fluid just 1/2 hour ago I drove it around and I don't notice a single symptom of a malfunction. It's getting all 4 gears and reverse just fine. I don't understand how that can be with a broken piston.

The only strange thing I've had going on lately is a 6-8 second delay engaging into gear on very cold mornings. But even then once out on the road it shifted fine.

What should I do about the broken piston? Just order a new one and pop it in? Again how can I tell which one to order?

Thanks in advance for any advice you can offer.

sixto · #2 02-08-2009, 02:49 PM

Good thing you were gone before they had a chance to reload

Sixto
87 300D

pelon · #3 02-08-2009, 02:56 PM

i was gonna say... look for the bullet hole in the pan.
that would happen i some areas up in ABQ for sure. richochete off the road into the tranny.

mobetta · #4 02-08-2009, 06:47 PM

maybe it was already repaired, but they forgot some extra parts in there.

compu_85 · #5 02-08-2009, 06:52 PM

I assume park works?

-J

deanot442 · #6 02-08-2009, 08:52 PM

it looks like the park lock pin

Flounder · #7 02-08-2009, 09:09 PM

Thanks guys. I hadn't thought of the Park locking pin. Although I'm pretty sure Park holds the car OK.

Can anybody ID this pin for sure?

BTW it's from my '81 CD, non-turbo.

Thanks!

81300sd · #8 02-08-2009, 09:48 PM

I just looked at my parts, park lock pin, B1 and B2 rod and the only one that had a tapered end as yours does was the B1 rod

B2 has a ball on both ends and the park rod doesn't have a tapered end.
Diameter of the B1 rod that I have is .250, park rod is .275 diameter.

Not sure what trans you have, but mine are from a 722.303

d71889b · #9 02-08-2009, 09:59 PM

maybe the end of the vacuum modulator? you say it shifts hard on cold mornings?

rs899 · #10 02-09-2009, 06:46 AM

Looks like one of the pistons. Whatever it turns out to be, if the transmission was basically working , I wouldn't worry about it. I am sure it must have failed and been replaced. Why it is still in the pan stumps me unless the tech never bothered to drop the pan...

Flounder · #11 02-09-2009, 08:51 AM

Thanks for all the replies. I took the car to work this morning (48 miles) and everything was fine. So maybe the piston was replaced 5 years ago and the previous mechanic just didn't notice it in the pan.

The other thing I found was the little metal pickup screen on the filter was about 70% clogged with crud, so I cleaned that off and I notice the delay engaging gear (when cold) is now gone. Maybe the tranny was just starved for fluid.

I'm going to order a filter kit from Phil and do the job right next weekend.

Thanks again guys.

rs899 · #12 02-09-2009, 08:54 AM

that part, whatever it is, actuates one of the two bands. When it went, it was pretty obvious....

vstech · #13 02-09-2009, 08:58 AM

I've got an 85 722 torn down, I'll look and see if I can match up a part on there...

ImBroke · #14 02-09-2009, 11:29 AM

Quote:

Originally Posted by vstech

I've got an 85 722 torn down, I'll look and see if I can match up a part on there...

Can I come down some weekend and get some trans training?

vstech · #15 02-09-2009, 11:42 AM

heh, I didn't tear it down, I had it in for a rebuild, and they told me there were too many broken parts to fix it... I know VERY little about working on auto's...