Originally Posted by Maximo

When a bearing leaks it usually breaths inwards, not leaks outwards...weeping fuel is of no concern, that the engine likely ingested dirt thru the front bearing is a much larger concern...do a test...fire the engine up, and while it is idling spray behind the flywheel with a shot of nitro spray...if the engine stalls then you know your engine is breathing thru the bearing...this can be a huge issue if you run on a dirty dusty track, as the engine will breath in whatever unfiltered air there is...usually causing flameouts and premature engine wear....ever wonder how guys can wear out a engine in under a gallon ? ingesting dirt thru the bearing will cause engines to wear extremely fast....what is even worse is that any dirt particles brought in thru the front bearing will get ground up extremely fine, which means it passes thru the engine without any of the telltale signs of ingesting dirt...the dirt gets ground soo fine in the bearing that it acts much like a lapping compound......it leaves no scratches or heavy wear marks, it just wears the engine out..... the silent killer of nitro engines..... if you run in dirty dusty conditions you need to make sure your engine is not breathing thru the front bearing...the brake cleaner test is a easy way to test this.... I think many people will be surprised by what they find when they do this test....