quote:The 5s engine was available in 2 different generations. The first 5sf engine used a block that is outwardly similar to the 3sf or 3sg, however it did not use a oil cooler under the filter, nor piston oil squirters. The 2nd generation of them used a totally different block, bulged out near the bottom and with counterbalance arrangement built in to the sump. These later engines have a crank to drive the counterbalance that is in the sump. Avoid these.