1985 380SE W126 Stalling - Fuel Pump Relay ?

[gmercoleza]

85 380SE approx. 130K, suddenly stalled on me today. Had done it only twice in the last 2 months and approx. 5,000 miles of driving since I got it, all I did was cycle the ignition key off and back on and it started right back up (did this while rolling both times, no need to pull over). Today, cycling the ignition didn't help and I ended up pulled over on the side of the highway. Thought I ran out of gas (fuel gauge not the most accurate) so had a friend pick me up, got gas can, added 2 gals., and it started right up.

On way to gas station, it stalled again. Same deal - wouldn't start back up. A fellow motorist helped me push into a parking lot. Called my wife to bring VOM and service manual, checked out diagnostic for fuel pump relay, and jumpered - car started right up. Removed jumper and put fuel pump relay back, car wouldn't start anymore. Replaced jumper, car started right up. Ran to store, got box of paper clips for 38 cents, stuck a paper clip in there and did the same test, swapping relay back in, and each time the relay was in it wouldn't start. Put paperclip back in and drove it all the way home without incident. Had to pull the paper clip when I got home because the fuel pump kept running (I guess that's why MBZ put a relay in there and not a paper clip).

I just ordered a fuel pump relay from fastlane because I'm 99 percent sure this is the problem. But can anyone else out there confirm my diagnosis? Is there anything else I should be looking at? FWIW, previous owner experienced something similar a few years back and resoldered the fuel pump relay - he said it never happened again after the soldering job and I know he drove it quite a while after doing so. When I pulled the relay out I noticed there is still clear silicone from when he re-sealed it. So I'm guessing something other than the solder joints failed inside the relay, like maybe the contacts or something?

Maybe the relay, after 21 years, is just finally ready for the bone yard... Any comments?