So, I take off my fuel pump realy to resolder it and find that it is full of dirty old water. Now considering how it was clipped on(sideways), and that the plastic housing is intact, how could this happen? I have had this car for about two years, and I am surprised this relay has worked this long. It is wasted. Any logical explanation?

This happened to my 87 last year. The cause was water entry at the wiper motor. I had just replaced the wiper motor (typical bad ground) and a week later a heavy rainstorm killed the relay. Mine was hanging loose on the harness- the water ran right down it into the upside down relay. Filled it completely and burnt it all up. Not saveable. If yours is not corroded too much, you could probably save it, but you might want to get a spare just in case. Costs less than a tow, that's the way I look at it.
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Rob Bareiss, New London CT ::: "Roterande Fläkt Och Drivremmar!"

Well, better damn well drain it and refill with 50% antifreeze or it could be a problem.

Well, I crossed my fingers and peeled back the carpet. Not only was it dry, it was the most rust free part of the car! The relay wasn't really full of water, it just had a little in there. I put the car through the wash a few days ago so I think if water was getting in it the carpet would still be wet. So I am chalking it up to 18 years of condensation. I resoldered and it works, also did the OD, and got a new one off of ebay for the glove box(just in case). Thank you Brickboard!

If it's really full o' water then - ahoy matey, she's takin' on water!!

So basically I agree with Don. I would put some tissue around and through that wire bundle and really soak the corner of the car (or the whole front including firewall) with a waterhose on full blast...then start finding where the water is getting in.

I have had some small condensation in my relays, but where I live is extremely wet.....and I doubt this is your case.
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www.fidalgo.net/~brook4

I bet the foam carpet underlayment is saturated. Maybe the floor has already rusted and the water simply runs out the holes.

Somewhere -- maybe around the windshield or around the wiper or around a through-the-firewall harness grommet -- water is sneaking in.

You can probably restore your relay by thoroughly washing its internals with warm soapy water and then rinsing, rinsing, rinsing. And then drying, drying, drying.

And then resolder the relay. Remount it so the lugs point downward (which is the normal orientation).

And also find and fix the leak.

Check your wiper relay for the same problem. It's on the driver's side, extreme left, under a metal plate under the carpet -- about where a tall driver's left foot might rest near the firewall. You can see wiring harnesses disappear behind the metal cover from up under the dash.

Pull the harness up and you'll find one or two relays plugged on the ends. The relays are usually wrapped in plastic foam.

Look under your car for rusty floorboards, maybe even the foam sagging through.
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Don Foster (near Cape Cod, MA)

The same thing happened to mine about 4 years ago(before I discovered this forum). Anyway, the car wouldn't start so I had it towed to the dealer. It was really cold and the water inside of the relay froze and stopped the relay from working. The mechanic opened up the relay, saw that it was and ice cube, and put it in the freezer to show me. Is it possible that these relays accumulate condensation over time? I am sure that my brick isn't taking on water from the passenger side firewall area.
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'86 240(original owner), 225K, Boulder, CO.

I can't imagine why condensation would select only the fuel pump relay to the exclusion of other relays. Keep in mind that condensation requires moisture-laden air to enter a cold area -- a spot where the ambient temperature is below the dew point. Only then will water gas become water liquid.

The fuel pump relay has two coils in it which generate a modest amount of heat when they're "pulled in." Moreover, the pump current flowing through the relay creates heat from the contact resistance.

I expect that the fuel pump relays run quite warm. This should depress the %RH inside the plastic housing, preventing condensation.

I think it's more likely that you have a tiny leak somewhere and the water was sneaking along the harness to drip into the relay (capillary action). The proper orientation for that relay is with the tabs downward. This forces the harness into a "U" configuration -- any water should drip off the low spot.
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Don Foster (near Cape Cod, MA)

Don, i had this happen to me as well. I remembered your trick with the paper clip, took me home 25 miles. Now I travel with a paper clip, spare relay, and have turned the relay upside down. Working on the leak source. Thousand thanks.

What's the paperclip trick? Sounds like an important one.
Jon 83 245