Coolant disappearing: Heater core leaking?

[wertyu78]

Hey!


I've been trying to figure out why my coolant has been disappearing for the last 3 weeks. The entire cooling system is only 14,000 miles old. I'm talking everything. I checked again tonight and no sign of leaking. It seems that every 50-60 miles I drive, the coolant warning light comes on. Sure enough, the float in the overflow tank is at the bottom.


So I'm thinking where is it going? I begin to think it could be a small headgasket leak, so I check the tailpipe and no white smoke. Pull the plugs and they look fine. Pistons are dry as should be. Put a pressure tester on the expansion tank and run the car, indicates head gasket is fine.. as it should be! Rebuilt the head 3,400 miles ago!

Okay, so it's not the head gasket and it's not the cooling system....but why does the gauge show I'm losing 3.5 lbs of pressure?

It's leaking somewhere..... I begin to remember last winter. I had a terrible problem with fogging windows and a very unpleasant smell. Perhaps it is in fact the heater core leaking. I dunno... help me out here!

[Avetiso]

Gonna hope for your sake it's not the heater core.

[wertyu78]

Gonna hope for your sake it's not the heater core.

I'm not looking forward to having to do it, if it is the heater core. But if it must be done then I gotta do it!

[Hermes]

put some newspaper down under your car when you get home and see where the wet spots are.

[wertyu78]

Drove it for 30 minutes last night to get it up to operating temp. Parked it in the garage and came out this morning to a clean floor.

[danewilson77]

Drove it for 30 minutes last night to get it up to operating temp. Parked it in the garage and came out this morning to a clean floor.

Obviously the splash shield underneath was removed.

[wertyu78]

Obviously the splash shield underneath was removed.

Yes, I took it off months ago.

[danewilson77]

I ran into a similar situation with a hailine crack in my expansion tank. You could not see the crack with the expansion tank installed. To make matters worse and even tougher to diagnose was the fact that it would only leak after the car was warm, and I was driving around.....so like you....I never saw anything in my troubleshooting, but level always slowly went down.

[wertyu78]

I ran into a similar situation with a hailine crack in my expansion tank. You could not see the crack with the expansion tank installed. To make matters worse and even tougher to diagnose was the fact that it would only leak after the car was warm, and I was driving around.....so like you....I never saw anything in my troubleshooting, but level always slowly went down.

Thanks Dane! Found some white residue on the inside of the expansion tank today. Hopefully it's as simple as that.


Still, I lost a whole expansion tank full of coolant in 15 hours....

[ejp2fast]

Thanks Dane! Found some white residue on the inside of the expansion tank today. Hopefully it's as simple as that.


.

so i would say expansion tank is culprit for small crack - thus replacement. keep us informed.