Torque Converter Drain Plug - PeachParts Mercedes-Benz Forum

#1 02-20-2003, 11:23 PM

Have an 86 420SEL. What is the best method to get the drain plug to appear in the window so I can open it. Tried cranking the engine a touch to line up but after the umpteeenth time it still wouldnt line up so I could drain it. Any help would be appreciated

ericnguyen · #2 02-20-2003, 11:27 PM

Also, please answer my questions:

1) What tool + size is used to remove the torque converter drain plug on a 1994 c220?

2) How much ATF can be drained from a torque converter?

Thank you in advance.

Eric

MikeTangas · #3 02-21-2003, 01:42 AM

Size - all of the TC drain plugs I've seen have been 5mm allens.

How to get it in position. Wrench the engine over by hand using a 27mm socket on the crank bolt. Be sure to turn the engine clockwise. I've found the I can lay on my back, feel for the plug through the window with my left hand while wrenching the engine over with my right. Gets the plug centered every time. Trying to get the plug in view using the starter is like trying to hit big on a slot machine - it just don't happen too often.

How much fluid is in the TC, probably about half of the total fluid amount. 3-4 quarts on both of my cars.

engatwork · #4 02-21-2003, 08:10 AM

Quote:

I've found the I can lay on my back, feel for the plug through the window with my left hand while wrenching the engine over with my right.

This is the way I do it too.

I will caution - be particular when you are "feeling" for the drain plug as you rotate the engine. You do not want to be pressing too hard on the torque converter. The drain plug can get the end of your finger and catch it between the side of the housing (pinch point). Learned this the hard way

.

Eric - if this is your first time you fill as follows.

After fastening everything back together (don't forget to use new crush rings) you will want to pour 4 qts in the tranny, start up the car and add another quart. I always go slow adding it after I have about 5.5 qts in them to keep from overfillling. Anyway after 5 qts or thereabouts you will want to drive it some and get it up to temp. Then check/add as necessary.

Early Bird · #5 02-21-2003, 09:54 AM

I found the plug by taking small bites of the Converter through that open area under the housing with a large screw driver . There is little ribs on the converter that the screw driver can grab. Thats small bites , you don't want to break anything on the housing. It takes awhile for that plug to show up, almost thought I didn't have one. MB dealer just gave me the 2 small washers for the plugs (tranny pan & converter). They said it wasn't worth writing up a bill for such a cheap part ..It turns out to be a very easy job. Just DON'T over fill that tranny. Also the 2 plugs have a torque that I don't remember

GregS · #6 02-21-2003, 10:05 AM

Mark the harmonic balancer with white paint (or make a note of the timing mark) so you don't have to go through this again in the future.

Greg
'84 300D
'90 300CE

Kestas · #7 02-21-2003, 06:26 PM

I use a hand held mirror extensively when I work on my car. You may want to place one in a strategic location instead of feeling for the bolt when turning the engine.

ericnguyen · #8 02-21-2003, 07:15 PM

Thank you all for your precious help and tips.

This site is terrific!

Eric

#9 02-22-2003, 10:58 PM

Used your instructions and what took me a half hour before took about two minutes. Am draining the TC as we speak. Thanks again

daddiojiggy · #10 02-23-2003, 07:50 PM

when you say clockwise where are you and where are you facing?

Early Bird · #11 02-24-2003, 10:02 AM

Daddio, excellent question. I have always went by direction engine turns, by standing in front of car looking at engine. When I see the direction the engine is running, thats the direction I will turn it. That works for me, but now I see telling someone else the direction could be tricky.

Kestas · #12 02-24-2003, 10:15 AM

I know it's good form to turn the engine in direction of rotation, but what bad can happen if you turn it the other way?

Early Bird · #13 02-24-2003, 10:21 AM

MB says that you can do damage to the timeing chain and or other parts that have to do with the chain. A continue habit of going the wrong direction I'm sure will cause problems.

#14 02-24-2003, 10:30 AM

With a chain driven over head cam motor, if you turn it over backward, you will put a lot of stress on the tensioner side of things (which wasn't designed to deal with such stresses) because the chain will be pulling the cam through the side which ordinarily just floats along, and in a few cases enough slack may develop on the side which normally pulls, to cause things to jump a cog -- this is even more likely on belt-driven overhead cam motors. In a few rare cases, the cam profile on the closing side of the lobe may also be so radical as to cause galling or jamming if it has to lift the valve open. On the other hand, if you have a gear driven cam on a pushrod engine, like an old Volvo or some of the German Ford V6s (also used in Rangers and Aerostars) you can turn them any way you please with no problems, and the same is _usually_ true of mildly tuned pushrod American V8s and V6s which have very short chains to the cam in the valley between the cylinder banks.