Messed up master cylinder install w124

[jdulle]

I was not very careful while installing a new master cylinder on my 90 300d. I put in the new cylinder somehow without the plunger going into the correct spot on the master cylinder. When I went to pump the brakes, I heard a clunk and dirty fluid dripped down in the foot well. When I took out the master cylinder I realized my mistake, but now the plunger is separate from what it is supposed to attach to inside the booster to the pedal. I am looking at the metal rod and wondering if I can re attach it somehow, but I can't see where it is supposed to attach. Perhaps I may need a new booster too.
Does anyone know how this fits together and what parts I might need?
thanks!

[jdulle]

It's funny because no one else seems to have had this problem. (I should have held my finger on it while I was sliding the new master cylinder in).

[BillGrissom]

If like my 1985 300D, I'm not picturing what you did wrong. There is no way I can think of for brake fluid to get past the booster to drip in the cabin. If the booster's output rod is flopping around, it may have separated from the large rubber diaphragm. I recall one booster where the output rod slips into a hole in the diaphragm assembly so can be removed, but might have been one of my 1960's Mopars. Like most such thin "pancake" boosters, there is a rubber vacuum seal between Master Cylinder and booster.

[jdulle]

So I think the fluid I am seeing is not from the master cylinder but from a separate cylinder in the footwell. I think the seal between the master cylinder and booster is fine. There is a black seal in the footwell, which I either popped off or tore that covers a wider cylinder that goes through the firewall. The part that is supposed to push the rod on the master cylinder has fallen off on the brake booster side and am not sure how to re attach it. I am trying to go from the other side to take it apart and see what is broken and figure out how to put it all back together.

New question: What is the easiest way to remove this cylinder? I have taken off the pin that holds the linkage to the pedal, but the assembly still won't slide toward the cabin. Do I need to remove the brake pedal assembly to continue?

[jdulle]

I am thinking I destroyed my booster. All the new parts images I see have the footwell boot as part of the booster, and I dont think the rod that engages the m/c rod is supposed to separate from the pedal/booster assembly.

[jdulle]

Maybe the fluid that came out was from the old master cyl? I am hoping...

[jdulle]

Just to follow up, I removed the booster, and found it partially full of brake fluid (a surprising amount). In a way I am glad that rod separated, because otherwise I wouldn't have known it was full of brake fluid, and might have rusted out anyway.