Lister TS1 air cooled Diesel 1 cylinder, 635cc 1985 - on No oil seals but includes valve stem seals. Equates to 657-32681 Weight of set and packing approximately 600g Pack size 310 x 430 x 40 The manufacturer recommends that the TS1 engine is overhauled after 6000 hours, including the replacement of all joints and seals. This proceedure will require a full gasket set.