If you can get to the timing cover, you can clean around it very well with MEK, must be oil free, and then smear on some silicone sealer with your hand.I recommend that you ware disposable rubber gloves.I have done this in the past and it is only a temparay fix.If it is leaing around the crank shaft you are out of luck.:
FORDS WILL STILL BE RUNNING WHEN ALL THE GENERAL MOTORS JUNK IS ON THE SCRAP HEAP!
Something else to keep in mind. If you have an oil leak that just wont quit. There may be another cause. The crank case builds pressure. If this pressure is not vented (pcv valve), you will have oil coming out of the weakest sealing area. If your engine has a few miles on it, this is most likely to be the valve covers, front seal or rear main seal. They all have an abundance of oil being splashed on them constantly.
A troubleshooting aid is to take a piece of paper about the size of a dollar bill. Remove the oil filler cap and lay the paper over the opening. Watch to see if the paper is being blown up or being sucked down. If it is being sucked down, your pvc system is working the best it can. If it is being blown up, check the valve for vacuum and flow.