Help! Hit dip and now my brakes are gone!
 

Ahhh, I need help!

This afternoon I was cruising in my 1980 450SL and I came up on a hidden dip in the road...the front end bottomed out pretty hard and then my brakes suddenly stopped working.

When I hit the brakes, it doesn't go all the way to the floor, and I have to press down REALLY hard to make it stop at all.

I took a look under the car and nothing is hanging or seems to be broken loose, and nothing is dripping or leaking.

Does anyone have any thoughts on what the problem may be, or what to look for to test?

Thanks!

Hard pedal is a result of a problem with the brake booster...

Alright, I guess that's a start.

Can you give me any direction in what I need to do to address this problem? Would it be something I can fix or do I need to replace the booster?

Any help is greatly appreciated.

Thanks!

Booster works of vacuum - did you knock a line off somewhere?

I'm not sure, I haven't gotten a chance to look very close yet.

Should I just look for a loose line between the vacuum reservoir and the booster?

Locate the vacuum line at the booster and work back towards the engine.

But don't discount a line knocked off somewhere else that is robbing the vac supply to booster. If that model has a tranmission modulator - take a look underneath at that line.

Found the problem!
 

Thanks everyone for your help with this, I had no idea where to even start looking, but after some of the responses I got, I was able to locate the problem!

As soon as I looked under the hood, by the Master Cylinder, I noticed that the check valve on the brake booster vacuum hose had completely broken in half. I ordered the part the other day and expect it to come in any day now. In the meantime I was able to temporarily fix it with duct tape, to ensure no vacuum loss, and now I have brakes again.

Thanks again!

Good deal. Everyone likes an inexpensive fix.