by ADRIAN » Sat Jun 13, 2020 4:41 pm
Remember that the early HB 1159cc engines did not have valve stem seals, and they cannot be fitted retrospectively. By early, I mean with 3/8th head bolts. Only heads with 7/16th head bolts have shoulders on the valve stems to fit seals. Perhaps yours is early 3/8ths and someone has fitted seals on the head incorrectly?
When you buy a head gasket set, 3/8th head sets do not have the 4 seals included in the packet, where 7/16th head gaskets sets do have them.
HB 1