My friend just got a 1987 Toyota pickup. At an idel, it drips this very strange brown water, Very Brown. Any clue to what this is.

I also must tell you that the rig has been sitting about 1 year, but the party he got it from clames that he did start it up once and a wile.

 

Sounds like residual moisture in the exhaust system. should clear up after running a while.

 

Soot on the inside of the exhaust making the condensation appear dirty would be my bet.

 

When a running engine is shut off, the change in temperature causes condensation inside the muffler (much like a chilled drink set out at room temperature) and therefore when restarted, this moisture is "pushed" out by the exhaust flow... this is the reason why mufflers rust out on cars, because they don't run long enough to evaporate all the moisture before being turned off again and the moisture sits in the muffler... my guess is the rusting process is being and the moisture is be tainted by the rust (turning the water brown)... this really isn't a big deal, just get a new muffler if it bothers you.