Coolant usage in 2003 Forester

sennat

2003 Forester XS, 120K miles, head gasket replaced at 60K. I suspect the head gasket is again failing. Symptom is that it uses about a pint of coolant every 500 miles. I don't see it leaking, I think it's being combusted.

I replaced the coolant recently with Subaru Super Coolant, and added a bottle of the Subaru leak stop. I'd like to keep this car going until the Forester redesign in a year or two - say, 20K more miles. The question is, can I keep just topping up the coolant, or is this a doomed strategy and I need to pony up the $2k+ for another gasket? Can I add another bottle of leak stop?

Thanks
Sennat

Mr_Shiftright

Never use stop leak unless it's an absolute last ditch, emergency situation where you need the car to work for another few weeks or so.

Sure you can keep adding coolant but you'd better keep a sharp eye on things--if you overheat, that engine could be done for.

One thing you might do is pressurize the cooling system with a pump and then pull the spark plugs out one by one. If it's a head gasket, you'll see coolant on the tip of the plug. Pressurizing it might also reveal a hidden leak that isn't head gasket related.