Flaming brakes + transmission wtf!?! - Page 4 - PeachParts Mercedes-Benz Forum

moon161 · #46 12-07-2013, 12:31 PM

PM & email sent.

arzueck · #47 12-08-2013, 10:37 AM

I do not know what diagnostic tests exactly were performed, as I won't be able to pick up the full report until tomorrow. The transmission is still in the car.

Interesting that the rear pump is considered "optional".

And I realize that $8k is an irrational number. The dealership does as well. Maybe I wasn't clear, but they were not actually trying to sell me that (or anything, really - they know that I can't afford anything more than the 2 hours labor they already charged me). I realize the part can be obtained elsewhere, or a replacement transmission.

Thanks again to everyone providing information and resources.

macdoe · #48 12-08-2013, 04:24 PM

Did the dealership get a pressure reading from the primary pump?

yvairguy · #49 12-08-2013, 10:57 PM

this is one of the reasons these cars end up in the hands of mechanics at the dealerships, someone brings in the car, they get a huge estimate and they drop off the pink because it's not worth the repairs so why bother paying the labor, just sign over the car....

Skippy · #50 12-09-2013, 05:33 PM

Sounds like a great excuse for a manual swap.

ROLLGUY · #51 12-09-2013, 08:55 PM

Quote:

Originally Posted by Skippy

Sounds like a great excuse for a manual swap.

Agreed. If this was all happening on the left coast, I might have already snagged up his TD and brought it back to life with the manual trans I have in stock!

arzueck · #52 12-10-2013, 08:37 AM

I may be getting a replacement tranny from CTH350. A manual would be great but I really only have a week or two to work with here.

The dealership's diagnosis was that the pump increased pressure which damaged the "clutches".

winmutt · #53 12-10-2013, 10:44 AM

$8k LOL. Just LOL. You can get a crate engine from metric motors for less than that... SMH. Good luck.

KCM · #54 12-10-2013, 08:25 PM

Quote:

Originally Posted by arzueck

I may be getting a replacement tranny from CTH350. A manual would be great but I really only have a week or two to work with here.

The dealership's diagnosis was that the pump increased pressure which damaged the "clutches".

Still don't understand how the pump could build up too much pressure and do damage when the transmission is designed to run on the pressure it builds. Maybe a pressure relief valve failed???

No matter. At least your getting right back up on the horse that bucked you off. I think all of us who work on or own these old cars feel beaten and ready to give up at one time or another. You just have to work your way through it. When you get it back on the road and cruisin', you'll feel much better.

97 SL320 · #55 12-10-2013, 09:49 PM

Quote:

Originally Posted by arzueck

I may be getting a replacement tranny from CTH350. A manual would be great but I really only have a week or two to work with here.

Have you found out what model trans you have?

Quote:

Originally Posted by arzueck

The dealership's diagnosis was that the pump increased pressure which damaged the "clutches".

?? ? First they said the rear pump was bad / not working and now it is a working rear pump that increased pressure resulting in clutch damage? Did they check line pressure with the engine running? How did they determine that the clutches were bad? Did they remove the trans pan?

A failed rear pump on a 722.3 trans won't cause loss of forward _and_ reverse motion. Also, all the "clutches" won't be damaged at once making the increased pressure diagnosis suspect.

Here is the apply chart for a 722.3 ( since no one has posted the actual trans model you have, I'm going with the .3 ) First and second do not use the same frictions as reverse. Also, first ( B2 + free wheeling unit ) and second ( B1 and B2 ) use brake bands, there isn't much friction here when released so the chances of them being damaged during towing is zero.

Reverse uses a brake clutch pack B3 + free wheeling unit + K2.

So, from a friction element standpoint, 1st / 2nd and reverse don't use _any_ of the same elements. The free wheeling unit is a one way sprag clutch ( like a starter drive ). This unit can survive on just a thin wipe of oil so there is no way towing hurt it.

Lets assume that the trans was towed forward with the shifter in reverse. The B3 and K2 would apply and should run the engine backwards. If the rear pump didn't make enough volume it could let those frictions slip, but not damage anything else leaving forward gears unaffected.. However, there might be a reverse apply interlock that drops everything into hydraulic neutral over X MPH.

If it was towed in a forward gear, the engine should rotate in the normal direction and the front pump will make pressure. At that point it isn't any different than driving with engine running.

Before you pull the trans, please do a few tests to that could possibly save you work. With engine running, pull the trans dip stick and see if it is very high or very low. Very high points towards sheared front pump lugs, at that point it is a trans out repair.

Very low points to an external leak / failed modulator as which point you will need to add fluid and try to run the car. ( Adding fluid and checking immediately will net a smeared stick so wait a bit for things to settle. )

Test line pressure with engine running, if zero, the front pump lugs are sheared, if very low it is a line pressure regulator problem.

With engine off, put trans in park and try to turn the drive shaft with a wrench. Having an output flange come loose then wear the splines out is common on high mile cars. Replacing the output flange is an in car repair.

sixto · #56 12-10-2013, 10:10 PM

An '85 TD would have a 722.315.

Sixto
87 300D

ROLLGUY · #57 12-11-2013, 01:11 AM

Quote:

Originally Posted by sixto

An '85 TD would have a 722.315.

Sixto
87 300D

The last time I did a trans service on an '85, the pan gasket was the wrong one (it had a 722.4 trans). The guy at NAPA said it was the correct kit for an '85, but the gasket was different. I had him look up a '95 E300, and it had the correct gasket. It seems that #126-271-11-80 (for 722.3) was the wrong gasket. The one that fit was #201-271-03-80 (for 722.4). The moral of this story is check the trans model before ordering parts, and don't trust NAPA's computer!

arzueck · #58 12-11-2013, 03:38 PM

Got the car back today. Sick to my stomach frustrated and stressed out by all of this.

97SL320:
Fluid was actually a little low now when I checked today. I added some, hoping for a miracle but no go. I'm asking the dealership now why it would be low, when it wasn't beforehand, and they stated it was enough. Trying to find out exactly what they did. I can't see where any has leaked externally.

I can't get under the car right now enough to find the numbers for the trans ID. I gave up for the moment when I sprayed brake cleaner in my eye. I don't have any of the tools for the pressure test at my disposal. Is it really possible that it's simply the regulator? How can one explain the incredibly bizarre timing for that part to go bad?

Shopping for Y2K era Subarus right now, which is depressing. Unless something miraculous happens I just don't have the time to work on this car right now + go through all the legal steps to try to get some money back from the tow company.

The insurance company wants a mechanic to pull the trans and "tear it down" so an adjuster can inspect. But if they rule it was not caused by tow them I'm on the hook for that too.

Anyone on Long Island have a line on a replacement trans? Manual conversion would be great too. CTH350 was in touch and was going to help me with a replacement trans, but has been incommunicado for 48 hours.

Zacharias · #59 12-11-2013, 05:21 PM

CTH has been around Mercedes forums for a long time and is an honourable person. If he said he would help, I am sure he is doing it but there are no overnight fixes stuff like this.

Really if you are that upset, I would just put it behind me and drop the insurance claim. If the company is demanding the trans be torn down, then it seems to me you are not dealing with a firm that is going to easily come to a settlement.

To even get it torn down you are into labour charges to remove it from the car and a shop may not be enthusiastic about having a complete trans laid out for inspection taking up space as they wait for an adjuster to arrive then poke around and quibble over what broke versus what wore out on an old transmission.

Sometimes disasters happen and it's just best to fix it and move on. The insurance company has a lot more time, money and experience in arguing than you do. (Voice of experience.)

ROLLGUY · #60 12-11-2013, 06:01 PM

I would suggest you replace the trans first (or manual it), and then have the autopsy done on the old one. I would not wait for the insurance company to pay for a trans rebuild before getting your car back on the road.