22re Expert Needed. Front Oil Seal Leaking Options

[giggi]

i bought a 1993 2x4 4 cly toyota pickup about 2 mths ago. after i got it home, i noticed a big bolt laying on the frame under front of engine. turned out to be the crank shaft pulley bolt. i was told the head gasket was just replaced before i bought it. not sure if they would have to remove the pulley to replace head gasket but if they did, they forgot to put the bolt back in. i was driving for a mth without this bolt in, crazy i know. anyway, in the meantime it started leaking oil from what looks like the front crank seal. i have yet to tighten the crank bolt properly, just tightened it untill the engine turns over, got to get something to hold pulley. after all that my question is..... if the crank pulley is not tightened correctly, could this cause my oil leak? i read in places that the back of the pulley is part of where the seal sits.