My wife's '86 sedan was running a little warmer than usual, so I take off the radiator cap & there's a black tarry substance all around the rubber on the cap & the top of the radiator where the cap touches. The radiator's clean, but unusually low. The stuff smells like rubber but the rubber on the cap is fine. The radiator's in great shape. I thought I smelled it leaking a while back, & thought that it was probably dripping onto the exhaust, so when I had it up on jack stands, I checked it out & everything was dry. I checked all of the hoses this time and snugged up one, that was a little loose. So what could that tarry stuff be? Any ideas? The car's running great. ('86 ea82 automatic sedan)

mabe the rubber seal on the radiator cap is decaying?

 

does your car smoke? (cigs)

hoses are rotting from the inside

hoses are rotting from the inside

 

That is what I am thinking also. How old are the hoses?

AHHHHH...light bulb clicks on, I should've thought of that....hoses rotting on the inside makes a lot of sense. I'll be replacing them this weekend Thanks!

 

Niku-Sama No my car doesn't smoke-- cigs or otherwise & the rubber on the cap looks good, except for that black dodo all over it. When I wipe it off, it looks fine. The hoses do to, but they are pretty old. I'm still losing some fluid, though. I just don't know where. I'll find it though. Thanks for the help, guys.

~Myles~