Engine only seems to leak when the crankcase is full.. Like after a change for a few days..LIke its leaking out of a certain point when the oil is full. I though the owner was nuts, but I did an oil chage and hes right. Any though on where to start looking?
Thanks

 

clean everything down with engine degreaser, top the oil up and then look for leaks. maybe a pan gasket or a dipstick tube seal.