What do you mean by "rings"? The core is a self contained unit. The air blowing through the fins is picking up leaking coolant and blowing it all over. You will need to remove the center console and then the black plastic heater box. This is not a fun job - but I don't see any other choice - except keep the bypass and forgo heat.
Good luck,
I was reading somewhere about there being some rubber rings in the core that could have deteriorated. I've never had one apart...like I said, maybe I read too much (into) things.
Luckily I don't really -need- heat where I am in SoCal but I also don't want anything to not work on this car so evenutally I'll fix it.
Guess I'll be able to get to the clock and fix it, too. The light at the clock works as does the light in the glove box. Only thing that doesn't work is the cigar lighter so I guess I'll work on it, the heater and the clock all at one time.
Are these hard to repair? I know that I'll probably just find a replacement one so i can get the job done in a day, but then I'll have the one that's leaking which I suppose I can get fixed and then sell off?