Cylinder head breather

[Slimboybinz]

Good wishes to all Street Gliders out there.

Some time ago I posted about high oil consumption and clouds of white smoke out of my SGS with only 2000 Km.

I did find that the pipe from the cylinder head breathers that should go into the air filter had been squashed between the throttle body and the airfilter .

When I corrected this the smoking disappeared and the oil seem to have stabilised.

Whilst this is good news, I would really like someone to explain exactly what happened and how a blocked pipe would cause my problem.

SLIM

 

[hulkss]

Blocking the breather caused excess crankcase pressure forcing engine oil past the piston rings on the intake stroke of the engine. This oil then burns on the following power stroke and exits the exhaust as white smoke.

From the factory service manual:

 

[BluesBelly]

Oil Inside the HD engine is pumped and pressurized into a mist that circulates throughout providing lubrication and also cooling before returning to the oil tank. Any excess oil that remains in the valve cover cavity is blown/sucked through the blow by tubes and into the throttle body mixing with fresh air to be burned in combustion cycle. Because it mixes with enough air to dilute it the oil burn will not smoke white. If the tube is pinched off the pressurized oil mist travels Down the valve stems and past the rings into the combustion chamber and burns in the combustion stroke. Without the benefit of added air the combustion charge is heavily laden with oil and burns white.

 

[BluesBelly]

Hulk said it best

 

[Slimboybinz]

Thank you both for your time taken.
This explains exactly my problem bluesbelly.
I am just amazed that my dealership couldn't solve my problem instead of just filling the oil up and asking me to monitor it!

 

[PROCK]

Can you just remove the rubber tubes and run without them? I

Sent from my SM-N920V using Tapatalk

 

[buckshot85]

I don't suspect you could block them because your motor needs to vent. If you let them vent to the outside you will have a mess.