If you put alot of oil in it after you run, like I do, yes the oil will seep out of the front bearing. A leaky front bearing will rear its head after/during running. There will be a large pool of fuel/oil under the engine and on the block and you will have the symptoms of an air leak. However, if you check the front bearing for air leaks it will always leak. Bearings are not a seal, the fuel between the crank and the block is what seals the front of the engine. The engine is too lean on the bottom, richen it up and you should be fine. If you do decide to change the bearings TKO are very good and the price can't be beat for ceramics.