Is my transmission failing? - Page 2 - PeachParts Mercedes-Benz Forum

Stretch · #1 05-07-2013, 12:34 PM

Quote:

Originally Posted by firstdiesel

biopete: I understand your thoughts, been mulling around with it for some time now.

Stretch: I think I've read your post about taking it to bits about 10 times already, and each time I get more courage to go all in! It seems relatively straight forward and for a few hundred more dollars I suppose you're right that it would be a rebuild. Fixing the parts that are somewhat "external" seemed safer than that brain with 50 springs!

...

Re-reading this thread I get a strange feeling that perhaps things aren't what they seem! The problem at the beginning was one of gears not engaging and now there's a problem with RPM related noises. Is there anything else that might be transmission related going on?

As for the thread you are talking about I assume you mean the 722.303 one =>

722.303 in bits photo shoot

If so please note this is just taking something to bits - there isn't any information about rebuilding it. You need to get hold of a manual for that.

Quote:

Originally Posted by firstdiesel

...
If time was spent everyday, not all day, how long would a rebuild take?

...

It depends on parts availability - I guess most people could rebuild a transmission in a weekend.

But do you really want to do this?

One of your problems might be fixed by changing the B2 piston (if that link I posted is correct). A rebuild might be overkill.

Quote:

Originally Posted by firstdiesel

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Is there a comprehensive list of parts, and what is a good US supplier?

...

At the top of the thread I started (link above) there are some links to part diagrams. I can tell you where to go and buy your parts in the US but the name will get XXXed out here!

Quote:

Originally Posted by firstdiesel

...

How different is my 722.315 than your rebuild post?

...and no, I wouldn't want to take it out twice after fixing part of the problem just for it to create more problems! Sound advice.

The .315 is very similar to the 722.303 - the biggest difference I have found is in the tail cone section where there's an "electronic" speedometer facility on the .303 whereas the .315 has a mechanical one (with a different lubrication system). That's about it.

biopete · #2 05-07-2013, 01:35 AM

I'd start with a valve body. You'll probably need that anyway. They are easy and can be cheap. I got one for 100.00 and another for 150.00. I wish I would have gotten a valve body when my trans first started acting up. Instead I spent a lot of money on flushing and additives. Then reverse went out and needed a new trans. Then after that I still needed a valve body. I think driving with the bad valve body accelerated the demise of my trans. And I think new fluid releases gunk in the valve body causing it to need real cleaning. Just thoughts though. I don't know anything about transmissions.

firstdiesel · #3 05-07-2013, 01:31 PM

Only thing different now, other than the noise, is more fluid leaking on the floor. That is what lead me to consider the seals and o-rings for the pump. Which in turn sent me down the T/C road (noise)....

Quote:

Re-reading this thread I get a strange feeling that perhaps things aren't what they seem! The problem at the beginning was one of gears not engaging and now there's a problem with RPM related noises. Is there anything else that might be transmission related going on?

I had a vac leak in the rear driver's side door lock actuator, but I replaced that with a new one and no vac problems at this time.
Here is a quick timeline:

Adjusted vac due to a quick 2-3 shift; fixed the problem
Starting off there seemed to be a slight hesitation before the transmission engaged
Started noticing fluid on the garage, small amt.
Changed fluid and filter (not TC, I know, idiot) and noticed foam that Stretch posted pics for me.
Seemed to be running okay
Started to lose 1 + 2 occasionally, not constant
Whining noise shows up a couple of days later at about 2000 rpms, not constant
More fluid leaking than originally
Whining becomes constant
Driving very gingerly and seems to shift okay and gets me around locally, 1-2 miles if needed.

As far as my thinking goes here, I'm no expert, just trying to think this through instead of just throwing $$$ and time at it in hopes of a solution. I do have access to another vehicle for 10 days or so coming up in a couple of weeks, which would be ideal for this project. That is why I was asking about length of time.

Quote:

As for the thread you are talking about I assume you mean the 722.303 one =>

722.303 in bits photo shoot

Any suggestions on where to get the proper manual?

It was both posts actually, the 303 and the Monster DIY.

Quote:

One of your problems might be fixed by changing the B2 piston (if that link I posted is correct). A rebuild might be overkill.

I'm kind of relieved to hear that a rebuild might be over the top.

Stretch · #4 05-07-2013, 03:12 PM

Quote:

Originally Posted by firstdiesel

Only thing different now, other than the noise, is more fluid leaking on the floor. That is what lead me to consider the seals and o-rings for the pump. Which in turn sent me down the T/C road (noise)....

I had a vac leak in the rear driver's side door lock actuator, but I replaced that with a new one and no vac problems at this time.
Here is a quick timeline:

Adjusted vac due to a quick 2-3 shift; fixed the problem
Starting off there seemed to be a slight hesitation before the transmission engaged
Started noticing fluid on the garage, small amt.
Changed fluid and filter (not TC, I know, idiot) and noticed foam that Stretch posted pics for me.
Seemed to be running okay
Started to lose 1 + 2 occasionally, not constant
Whining noise shows up a couple of days later at about 2000 rpms, not constant
More fluid leaking than originally
Whining becomes constant
Driving very gingerly and seems to shift okay and gets me around locally, 1-2 miles if needed.

As far as my thinking goes here, I'm no expert, just trying to think this through instead of just throwing $$$ and time at it in hopes of a solution. I do have access to another vehicle for 10 days or so coming up in a couple of weeks, which would be ideal for this project. That is why I was asking about length of time.

Any suggestions on where to get the proper manual?

It was both posts actually, the 303 and the Monster DIY.

I'm kind of relieved to hear that a rebuild might be over the top.

I don't really know what is best - all I can do is give you some advice that might help and then hope that I'm not wasting your time. At the end of the day you and only you are responsible for all of this...

...I think you need to do the following instead of going down the rebuild route. There's always time for that if it doesn't work out - and what I'm going to suggest doesn't add to the cost of a rebuild. So although you could loose time; at least you won't loose money! I can't provide a solution that will stop you from loosing both => if anyone else can please say.

I reckon you need to get some hydraulic pressure gauges to measure what is going on. I can provide the test pressure data you'll need. You also need a vacuum gauge if you don't have one.

(After rebuilding a transmission you'll need these gauges anyway 'cos you have to set it up)

You need to find what's leaking - this might dictate transmission removal anyway in which case other things could be considered.

Replacing the B2 piston is a relatively simple task. If you struggle with this then you at least know that rebuilding a whole transmission yourself is something you probably shouldn't be doing. Furthermore this could fix the problems cheaply - it could - it just might - there's a glimmer of hope!

Also I feel that changing the fluid completely with a filter is a small monetary gamble that might pay off.

Stretch · #5 05-07-2013, 03:17 PM

Sorry forgot to say =>

Type this into google

ATSG 722.3 filetype:pdf

firstdiesel · #6 05-07-2013, 03:33 PM

Quote:

At the end of the day you and only you are responsible for all of this...

Stretch, no truer words could be spoken!

I've done front suspension rebuilds, took axles off, changed flex discs, rebuilt brake calipers and at some point I will be removing the rear subframe(a little while after tackling the transmission.) of course after referencing your thread on that! So mechanically, I get it, but I'm no mechanical engineer. Just a regular guy who likes to get his hands dirty and do some wrenching. I have a firm grasp of complex systems, flying turbo fans for the better part of 12 years, but I've never gone toe-to-toe with an automatic transmission!

Sounds like a good strategy, small steps and if it needs to be rebuild I will have those parts already.

Thank you for your time and help. Course you might get a PM if I screw something up!

Quote:

Sorry forgot to say =>

Type this into google

ATSG 722.3 filetype:pdf

Will do.

firstdiesel · #7 05-07-2013, 03:38 PM

Oh, that's nice! Thank you.

junqueyardjim · #8 05-07-2013, 04:36 PM

Well I think the OP is on the wrong tract. He is short of funds and he needs transportation. If he can get this one on the road with external low cost fixes, great. If he really doesn't know if he is capable of even pulling the transmission, how in the world is he going to overhaul it. It ain't going to get done. STRECH is a very special individual. He has a life time hobby of taking things apart and putting them together correctly. He has developed skills. Few people other then highly trained technicians can do those overhauls. Look here on the forum and try to buy a known functioning used one. If none is available get one from the junkyard. Try to find one on a wrecked car - your chances of having a working transmission is better if the car was wrecked in the not to distant past. Don't worry to much about an exact match. If you can find one that looks good on an 84, good, go for it. But if it is another model year, it might be a little different, but it will work. For an untrained person to jump into overhauling an automatic transmission is just plain nuts. Don't do it. After you install a used one and have your car back on the road, well then it might be the time to look into that transmission just for the fun of it. But for most folks that would not even be fun!

Stretch · #9 05-08-2013, 03:16 AM

I think it will be OK Jim! I think firstdiesel is planning on doing some more investigative work before starting on a semi-rebuild. Depending on from where the leak(s) is/are leaking and from where the weird noise is coming, and the outcome of some pressure tests; the most adventurous fix will probably be the B2 piston.

firstdiesel · #10 06-10-2013, 01:27 PM

In a word, YES!

Well, I removed the transmission to reseal the front pump using DIY articles from here and when I removed the pump, voila!

This is where my knowledge of this situation comes to a screeching halt, and I humbly bow to the expertise and wisdom of the forum.

What now?

I see three options:

Rebuild
Replace w/ rebuilt
Replace w/ used lower mileage trans and try my hand at a rebuild with no specific time constraints as a matter of learning and keep it for a later date.

I am leaning toward the latter for cost purposes, but I do not have a line on a reputable source in South Florida and I can't imagine that shipping is inexpensive, these things are heavy!

Stretch, would you tell me what part of the lubrication system differs on the .303? Can I still use it and swap the tail cone from my current trans? I'm just thinking of options if I have trouble locating a lower mileage .315.

I eagerly await your replies.

Todd

Stretch · #11 06-10-2013, 05:00 PM

That's buggered - sorry. The brake drum will be damaged as well. That's the same trouble with the .303 I've taken to bits so I can't even send you parts I've got (well I could but they won't help you 'cos they are knackered too).

Do you have a .303 as well then?

Get in touch with vstech about the tail cone swap - he's done it I think. Going from transmission to the other is OK but the other way round isn't - I can't remember which and I've never done it.

If I were you I'd do a WTB ad here on the forum and see if anyone can help. Shipping won't be mega cheap but you never know the whole package might not break the bank.

Stretch · #12 06-10-2013, 05:04 PM

Not cheap but includes shipping

Mercedes 300D 300CD 300TD Transmission re Manufactured | eBay

firstdiesel · #13 06-10-2013, 05:08 PM

Quote:

Originally Posted by Stretch

Not cheap but includes shipping

Mercedes 300D 300CD 300TD Transmission re Manufactured | eBay

I was looking at that one earlier this week. Found another online site I mentioned earlier in the post that has a good warranty as well. I was just hoping for a recommendation.

firstdiesel · #14 06-10-2013, 05:06 PM

No, I don't have any other transmission at this time, but when I find some options I just wanted to know what I can get.

I'll see if some of the other members may have one they are willing to sell and if anyone knows a good, trustworthy place in S.Florida I'd be mighty appreciative.

Thanks for the offer Stretch, but I think shipping from your neck of the woods would be even more!:-D

Stretch · #15 06-10-2013, 05:09 PM

Quote:

Originally Posted by firstdiesel

No, I don't have any other transmission at this time, but when I find some options I just wanted to know what I can get.

I'll see if some of the other members may have one they are willing to sell and if anyone knows a good, trustworthy place in S.Florida I'd be mighty appreciative.

Thanks for the offer Stretch, but I think shipping from your neck of the woods would be even more!:-D

Well I wouldn't get the almost right one (.303) if it wasn't especially cheap.