Tranny leak, not pan. - Page 2 - PeachParts Mercedes-Benz Forum

leathermang · #16 05-16-2015, 08:53 AM

I have seen leaks which ' continued' after a fix.. just from slowly making its way down the block or something... so that is your best bet now... and cross fingers...

Stretch · #17 05-16-2015, 09:24 AM

The procedure in the FSM - well the maintenance manual - can be found here =>

http://www.startekinfo.com/StarTek/outside/11832/Resources/201Create/PDF/80001a.pdf

It takes a long time to download.

Without a decent thermometer you are in danger of not getting a good reading on the dipstick - the when cold approximations are also given in the maintenance manual which are useful - but somewhere in chapter 27 (I think - EDIT also given in MM!) which is not widely available in the English translation there is mention of the correct fluid refill quantity. To my mind that's the easiest method of making sure you have the correct fluid - but hey each to his own.

leathermang · #18 05-16-2015, 09:45 AM

Quote:

Originally Posted by Stretch

..... To my mind that's the easiest method of making sure you have the correct fluid - but hey each to his own.

That would be correct for something like a rebuild...
you do not know if there are pockets of fluid which do not drain by gravity.. or how much just sticks the surface.. or how long it would take for ' all ' of that to drain out... that is why they give the method which is FAIL SAFE for adding in every other situation than a total rebuild.

Stretch · #19 05-16-2015, 10:56 AM

Quote:

Originally Posted by leathermang

That would be correct for something like a rebuild...
you do not know if there are pockets of fluid which do not drain by gravity.. or how much just sticks the surface.. or how long it would take for ' all ' of that to drain out... that is why they give the method which is FAIL SAFE for adding in every other situation than a total rebuild.

...and they also specify the total amount of fluid in the transmission and how much fluid you need to add for a refill!

Frank Reiner · #20 05-16-2015, 11:03 AM

Hounds:

Stretch made a very good point by mentioning the possibility of discharge of fluid from the vent. I agree with him. The vent is on the top of the trans case just forward of the output shaft/rear seal area. When fluid is discharged on the top of the case it can run back and drip off just above the output seal. If you are satisfied that fluid is NOT coming from the vent, then turn your attention to the seal, but a little patience now may save you the trouble of a seal replacement.

leathermang · #21 05-16-2015, 11:31 AM

Quote:

Originally Posted by Stretch

...and they also specify the total amount of fluid in the transmission and how much fluid you need to add for a refill!

Really.... how would they know whether someone had drained the torque converter ... things like that...
are the reason they give a ' bottom line ' measurement on the dipstick for the final word....the FAIL SAFE method which allows for accidental variances in the possible intervening variables....

Stretch · #22 05-20-2015, 07:10 AM

Quote:

Originally Posted by leathermang

Really.... how would they know whether someone had drained the torque converter ... things like that...
are the reason they give a ' bottom line ' measurement on the dipstick for the final word....the FAIL SAFE method which allows for accidental variances in the possible intervening variables....

You are making stuff up again.

The FSM gives two values - if you get stuck and you want to be sure - draining the transmission as specified in the FSM and then measuring the amount of fluid that goes back in is not a daft thing to do. You can then always compare that with reading on the dip stick at the correct temperature in accordance with the FSM if you wish.

leathermang · #23 05-20-2015, 07:36 AM

Quote:

Originally Posted by Stretch

You are making stuff up again.

The FSM gives two valves - if you get stuck and you want to be sure - draining the transmission as specified ......You can then always compare that with reading on the dip stick at the correct temperature in accordance with the FSM if you wish.

I assume you meant ' values' and not ' two valves' ....

You CAN do all sorts of things... you can compare anything you want... but you are making up things to do ..... as long as you end up not overfilling or underfilling according to the DIP STICK and proper checking conditions you will be in good shape... it is the bottom line fail safe requirement specified you know where.

Hounds · #24 05-20-2015, 08:56 AM

OK guys. Update.
First of all it seems I didn't tell-all in my original post. I DID measure the resulting amount I drained and put that much back in after about 20 minutes of draining.
HOwever, after driving it around some more for a longer period and at higher speeds the dipstick now reads about 1/4 inch above the high mark again AFTER I drained a bit more out a day or so ago.
It does not appear to be leaking anymore, or at least as MUCH. Should I continue to drive it for an hour , rechecking and taking more out if needed until dipstick reads in the middle of the H L marks? Since I don't have a surefire method to take the temperature at which it is supposed to be read, is there any 'more or less' method of time running at a certain speed or whatever?
Thanks. Its really getting me worked up now. lol
I think before I may not have driven it far and fast enough. In other words not hot enough to get a good reading ?
Thoughts?

Stretch · #25 05-20-2015, 09:36 AM

Quote:

Originally Posted by leathermang

I assume you meant ' values' and not ' two valves' ....

You CAN do all sorts of things... you can compare anything you want... but you are making up things to do ..... as long as you end up not overfilling or underfilling according to the DIP STICK and proper checking conditions you will be in good shape... it is the bottom line fail safe requirement specified you know where.

Thanks for pointing out the spelling mistake - I have corrected it

Quote:

Originally Posted by Hounds

OK guys. Update.
First of all it seems I didn't tell-all in my original post. I DID measure the resulting amount I drained and put that much back in after about 20 minutes of draining.
HOwever, after driving it around some more for a longer period and at higher speeds the dipstick now reads about 1/4 inch above the high mark again AFTER I drained a bit more out a day or so ago.
It does not appear to be leaking anymore, or at least as MUCH. Should I continue to drive it for an hour , rechecking and taking more out if needed until dipstick reads in the middle of the H L marks? Since I don't have a surefire method to take the temperature at which it is supposed to be read, is there any 'more or less' method of time running at a certain speed or whatever?
Thanks. Its really getting me worked up now. lol
I think before I may not have driven it far and fast enough. In other words not hot enough to get a good reading ?
Thoughts?

A casual observer reading the FSM might assume that checking something as simple as a dipstick is indeed a simple process! Unfortunately you are not the first person (or probably the last) to struggle with this. Mercedes transmissions can be pretty tricky beasts. (Meaning it isn't "you")

If you can borrow one of those fancy (now quite cheap) IR thermometer guns then you should be able to get a quite reliable temperature reading on the underside of the transmission oil pan. Failing that an old fashioned thermocouple and a multimeter would mean a fair amount of scrabbling about under the car. The Mercedes special tool goes down the dip stick tube for this job.

As for the leak - I would hope by now that it would have stopped dripping. If it has not I think you need to spend some time cleaning and investigating to make sure it is residual fluid and not new fluid leaking out.

Zulfiqar · #26 05-20-2015, 10:03 AM

there is a page in the FSM that tells you the fluid level on the dipstick with cold ATF, cold meaning that the transmission had an ATF recharge 5 minutes ago. On my 722.4 - that level is right where the dipstick curls up and becomes a pointing arrow. - Something like 11mm lower than the 30C mark.

After a good long run it always shows up right at the 80C mark.

The 722.3 have something like a 5mm below 30C mark measurement.

Stretch · #27 05-20-2015, 01:16 PM

Quote:

Originally Posted by Zulfiqar

there is a page in the FSM that tells you the fluid level on the dipstick with cold ATF, cold meaning that the transmission had an ATF recharge 5 minutes ago. On my 722.4 - that level is right where the dipstick curls up and becomes a pointing arrow. - Something like 11mm lower than the 30C mark.

After a good long run it always shows up right at the 80C mark.

The 722.3 have something like a 5mm below 30C mark measurement.

This is shown in the maintenance manual (for link see above) - still need to have a pretty good idea of the temperature =>

SD Blue · #28 05-20-2015, 01:26 PM

Quote:

Originally Posted by Hounds

OK guys. Update.
First of all it seems I didn't tell-all in my original post. I DID measure the resulting amount I drained and put that much back in after about 20 minutes of draining.
HOwever, after driving it around some more for a longer period and at higher speeds the dipstick now reads about 1/4 inch above the high mark again AFTER I drained a bit more out a day or so ago.
It does not appear to be leaking anymore, or at least as MUCH. Should I continue to drive it for an hour , rechecking and taking more out if needed until dipstick reads in the middle of the H L marks? Since I don't have a surefire method to take the temperature at which it is supposed to be read, is there any 'more or less' method of time running at a certain speed or whatever?
Thanks. Its really getting me worked up now. lol
I think before I may not have driven it far and fast enough. In other words not hot enough to get a good reading ?
Thoughts?

What I've found works best is to set the level to the minimum mark, at operating temp. This gives you room for expansion when the tranny really heats up.

Zulfiqar · #29 05-20-2015, 02:29 PM

Quote:

Originally Posted by Stretch

This is shown in the maintenance manual (for link see above) - still need to have a pretty good idea of the temperature =>

when I first did the ATF change on my E300D I simply followed the technique I wrote, it was perfect.

I think that is more to do with the fact that cold for me meant ambient temperature which was about 25C, I believe the ATF was the same temperature too.

I later found the temperature probe of my multmeter which I put in an open ended plastic tube and sent it down the dipstick tube, I tested the temperature before starting in the morning and it was only 2 degrees colder than ambient

Stretch · #30 05-20-2015, 02:45 PM

Quote:

Originally Posted by Zulfiqar

when I first did the ATF change on my E300D I simply followed the technique I wrote, it was perfect.

I think that is more to do with the fact that cold for me meant ambient temperature which was about 25C, I believe the ATF was the same temperature too.

I later found the temperature probe of my multmeter which I put in an open ended plastic tube and sent it down the dipstick tube, I tested the temperature before starting in the morning and it was only 2 degrees colder than ambient

Oh to live in a climate like that=> I bet the average temperature for most parts of the year is closer to 5 degrees C round here!