So I locate the source of my coolant leak, and yep, it's at the firewall where the coolant flows to the heater core. The copper fitting that the hose goes over is pinched pretty bad. I tried to give it a beter shape with some pliers, but it's not holding. Anyone know the best way to take care of this?

 

Clean the pipe up really well with some acetone or other good solvent, get some black RTV and spread a good layer all over (enough to fill any voids that are created with the "kinks" in the hard line), and wiggle the hose back on, as straight as you can to prevent displacing the RTV that's filling the gaps. A new hose would be optimal, but if the old hose is cleaned internally fairly well, it should work (the coolant has oils in it- RTV doesn't like oily things). Let cure for at least 30 minutes before tightening the clamp, then perform a pressure test.

 

I had trouble sourcing that hose without special ordering it. IIRC I just used a piece of universal coolant hose from NAPA. That thing still leaks every now and then. Wayny's method should clear it up pretty good. The alternative would be to remove the entire dash and replace that pipe. Trust me, you'ld have to set asside MANY hours to get that done. goodluck/.

 

Yeah, removing the dash was something that I definately wanted to avoid.

Actually, that hose is only a few weeks old. I lost the old one due to the infamous oil filter pedastal O-ring leak, and got a new one from mazdatrix (~$30). That's when I first noticed that the fitting was mushed, but I figured that since it was holding before that...

Thanks for the fix, Wayne. I've got some red RTV at home, I'll pick up some black on the way from work.

 

Red RTV should also work, if you can't get your hands on any black. I use black for coolant hoses because it color matches better than red (duh), and because because it's a bit more pliable (rubbery) after curing...

Cleanliness before application is your best chance at success...

 

Hey wayne, you have a webpage or text that lists the different types of RTV and their characteristics?

 

damnit damnit damnit.

I can't get the stupid thing to seal. I'm going to try and replace that crappy hose clamp with a better one. Also, I'm using the blue flavor of RTV (says it's good for coolant related applications on the tube).

Got halfway to work today, and my favorite buzzer went off. When I got to work, my engine was steaming happiness, but it looked like coolant had escaped from the thermostat cap. Time to replace that, too.

Can I just use a standard pressure cap for this? I have an overflow line going from there to the reservoir, but I also have an overflow line going from the rad filler nedck to overflow...

 

As a temp fix, block off both heater core hoses on the radiator ends until you can get good means to fix the problem. There will be a bit of residual coolant flow out of the heater core from time to time, and you won't have heat-- but the car will be driveable--if its a daily driver.

 

Bump for closure.

I was about to do that, just so I could get to work and back (I was stuck here yesterday), but I'm thinking I just didn't close the thermostat housing cap all the way.

On a good note, the RTV fix seems to be holding. Thanks again, Wayne and Kenteth.