BMW K75 | Glow descharges near inlet pipe,injectors
I got recently a 1996 BMW K75. The last owner left it on the sidewalk for three years, ‘cause not running any more. He says, an inlet pipe is cracked.
I’ve good experience in bike repairing, down to the crankshaft, but no one in injection.
After a first oil change (a second will follow after warming up the engine), I tried to start the bike.
It runs hardly, and I’m able to keep the engine on only through nervous throttle actions.
It “coughs” loud explosions from the upper engine area. In the darkness, glow descharges appear between inlet pipe and injector. At the beginning they seemed to come from the front cylinder. After swapping the first and the second injector, both cylinders flash. But it’s not easy to determine if the source is the inlet pipe or the injector.
Spark plugs are brand new and correct. They spark bright.
Valve clearances are correct.
Rubber pipes seem to be in good conditions, so far I can see and feel without desassembling the whole bike.
Is it possible that too much fuel is flowing down (fuel pressure regulator failing, i.e.)? What would ignite this exceeding fuel?
In case of stucking valves, do the pistons hit against them in a K-engine?
Btw., blowing compressed air in the spark plug hole moves the engine.
Please, need help. Any suggestion?
P.S.: Apologies for my English