My 2002 Freelander with 120,000 miles has a real small coolant leak. Have to add a little to reservoir about once a month. No coolant in oil and no external leaks so assume it is a small head gasket or manifold leak. Plan to pull the heads and install new gaskets and check the cylinder liners when I change timing belt at 140,000 miles. Want to find a good sealant to add to coolant to seal the small leak in the meantime so it doesn't become an issue. Any recommendations as to what does (or doesn't) work? Does Land Rover recommend anything? Dozens to choose from ranging from the simple silver crystal type to the high dollar Blue Devil which requires removing thermostat and flushing the system. Don't want to use anything that will clog the thermostat or cause any new problems.

 

1. Don't use Blue Devil sealer. Ever.

2. You may not need sealer. The Freelanders have more hose clamps per pound than any Rover vehicle. And of course any could leak. You can rent/borrow a coolant pressure tester and pump it up to 15 PSI and wait for 30 minutes for leak to appear. Easier to hunt for leak when engine is not whirling aound.

3. If your cooling system is brand new, maybe no problems. With 120K, you may have some build up of calcium in the radiator. Add any band of sealer, and those partially blocked rows can become fully blocked, and you have 2/3 of a radiator.

4. I would just add the little each month.

 

Don't use any sealer. The Freelander engines are notoriously failure prone, there's no way I'd add anything to hasten that inevitable event.
Rent a cooling system pressure tester and find the leak.

 

I agree with Tom, never use a stop leak product in your engine, better off to add coolant every week or so and start saving your money.
BNy the way, where is the leak located.

 

For those interested, here is the cooling layout of a Freelander, you count the clamps....