FatCat dropped off his stock FL350
Engine the other day and a really cool liquid cooled top end, someone welded on a water jacket to the cylinder then used a Rands head, really cool.
Plan was to have me swap the top ends for him.
When he dropped it off he said he had a problem with it running lean last time he was riding, automatically "pressure test" comes to mind....
When he dropped it off it was caked up with years of dirt and grease so I sealed it up and washed the Engine to get the first layers of shit off before removing the top end.
After it was somewhat clean I added air, pump it to 10 psi and it almost instantly drops to 5 psi then to 0 psi in about 15 seconds, huge leak, I stick the vent tube from the balancer mod he did up to my ear can feel air coming out, not good, remove the balancer side cover sure enough the balancer side crank case seal is leaking.
A air leak or a leaking seal is a big thing if not fixed or noticed it can cost you hundreds of dollars, what happens is your sucking extra air into the Engine threw another passage and not the carb if the air is not flowing through the carb its not picking up the required amount of gas and this creates a lean condition then you end up melting your piston, if all you need is a new piston kit and gaskets and you can simply hone the cylinder your still looking at 200.00 min. not including the down time you suffered.
You don't have to pull the Engine to do the pressure test as seen in these pictures but you will need to pull the exhaust and at least the carb off the intake and unhook the pulse line to the fuel pump.
Its a pain but its not hard to do well worth the time you invest if you have a bad seal and suck dirt and air it can cost you hundreds of dollars if you discover this later on.