30. Radiator Sealants - Don't use them except in an emergency
For years, Jaguar recommended the addition of "Barr's Leaks" to the cooling system at every system flush. They don't recommend it any longer, and for good reason. This stuff settles down into the lower radiator and clogs it up good, requiring professional disassembly and cleaning. Don't use Barr's Leaks or any other radiator sealant except in an emergency. If your system has a leak, get it fixed. A clogged radiator will cause overheating, and overheated engines drop valve seats ($$$).
See our Jaguar Parts Store Catalog to order parts.