She just won't move??!! - Page 2 - PeachParts Mercedes-Benz Forum

rs899 · #16 03-05-2009, 09:36 AM

You need to find the problem first. My thinking is that it is going to be either the TC and/or the front pump. Pull it out and let us know what you find....

bio350 · #17 03-05-2009, 02:22 PM

Okay, the rain finally broke so now I can get back to my hobby.
The torque converter spins fine with the flex plate, no problems there. I definitely do not have pressure.
I don't know how the tabs could not be lined up with the pump if it went together so easily.
If I do have a "big slug of air" how would I bleed that out?
I am ready to drain the fluid, drop the pan and recheck the filter to make sure it was seated properly.

kingdoc1 · #18 03-05-2009, 05:00 PM

Some questions:
1. Why did you change the torque converter at all?
2. Are you sure the two converters are 100% interchangeable?
3. When you installed the converter, did you fill it with fluid first?
4. When you installed the converter are you sure it was completely seated in the front pump, exactly the same distance from the front edge of the transmission as the old one?
5. Did you replace the front pump seal?
Just some things to think through, and the answers to these questions might help us to pinpoint the problem. I'm leaning toward the diagnosis that the torque converters LOOK the same but they are not interchangeable. If you have researched that angle already, then we could look at either improper installation, or the unlikely (IMO) that your front pump simply picked this time to fail.

sixto · #19 03-05-2009, 05:23 PM

Someone else asked but I didn't see an answer - did you install the 300 torque converter dry? Did you drain it before removing it?

At this point I'd drain the tranny and torque converter and make sure at least 7 quarts goes back in.

Sixto

bio350 · #20 03-05-2009, 05:49 PM

I put the two converters side-by-side and they were identical. I didn't know if I should go with the one that came with the motor or the one that came with the transmission. I decided to go with the one that matched the plate.
I drained the TC before putting it in. I just got in from draining the transmission and removing the pan. Everything looks okay.
But I will also drain the TC and then start over from that point, before dropping the transmission and starting over even further in.

sixto · #21 03-05-2009, 06:08 PM

Stall speed can vary between identical looking torque converters. I'm sure there are other parameters that can be different as well. The differences between 300 and 350 torque converters wouldn't be significant enough to cause the issues you're having.

Sixto
87 300D

kingdoc1 · #22 03-05-2009, 06:18 PM

Were you able to drive the donor car before you did the swap? Is it possible the converter you put in was bad and you had no way of testing it? After reading your original post, it seems you did add fluid as needed, kind of seems unlikely it is just low on fluid. If the converter was empty, the pump should fill it, thus lowering the fluid level in the pan, I would think, so you would notice low fluid when you checked it. I don't know if it is possible for the pump to "lose its prime" so to speak if the converter was completely drained, but it doesn't make sense because I have never heard of anybody having these issues with a fluid change when they drained the converter as well. Maybe an obstructed (or defective) filter?

bio350 · #23 03-05-2009, 06:47 PM

Yes, I drove the donor car home on the freeway, it ran beautifully. What a ride (350SDL) compared to my 350SD. Smooth!!!!!
I just drained all the fluid from the TC and am in the process of checking over the filter. Getting ready to button it all back up and try it out.

babymog · #24 03-05-2009, 07:04 PM

I would have used the 3L torque converter on the 3L engine also. Its stall speed is likely matched to the output of the 3L engine, not the lower power curve of the 3.5L.

Good luck, I hope you get it ironed out.

kingdoc1 · #25 03-05-2009, 07:04 PM

I sure hope the fluid change works. The problem really has to be related to changing the converter or filter, since both transmissions were functioning just fine before the swap and the only things you have changed on the trans is the converter, the fluid and filter.

bio350 · #26 03-05-2009, 08:01 PM

ARRRRRRGH!!!!! The fluid change didn't work. I still have no pressure and no movement at all.

I have to work for the next 48 straight so hopefully Sunday I can get to it. It's probably better that I have a couple days away from it.
I'll drop the transmission pull the TC off and put the other one it.

By the way, yes, I did replace the front seal.

kingdoc1 · #27 03-05-2009, 08:10 PM

Well, it looks like you have narrowed it down to one of two things, either the front pump is not being driven by the drive lugs on the torque converter hub, or the pump has failed completely. At least you have another trans that works if you have to swap them.

bio350 · #28 03-05-2009, 09:19 PM

I just wanted to be done!!! I have to put a new Injection Pump and pull and clean the injectors in my sons Dodge 250.

I am using my Dodge 350 as a commute vehicle. At least with the Gear Vender it gets 28mpg. And on biodiesel it's not so much the fuel as it is the beating I take going down the freeway.
I miss my Benz!!!!

DeliveryValve · #29 03-05-2009, 09:33 PM

Hopefully it is a simple thing like the torque converter is not seated properly in the slot and all other things are good.

Oracle12345 · #30 03-05-2009, 09:38 PM

was it working before the engine swap?

If was doing it before the swap then its something with the tranny but if just started now then you messup somewhere and need to retrace your steps

looking at some bulletins could be a few things. To see if your oil pump is working put the car in P then D and loosen the lines to the ATF cooler in radiator and see if ATF comes out if it does not then you have found your problem

You may have a stuck shift valve in the valve body of the tranny