After seeing the amount of oil sitting in the intake and air filter I am thinking about doing a breather bypass. I do not fully understand the dynamics of the breather system so I want to ask a question. For those that know everything please humor me if this is a stupid question.

My understanding is the breather system is used to remove the built up pressure due to ring blow by. What I don't know is if the pressure in the crankcase pushes all the gasses out or if there is a vacuum created since the discharge tube is in the intake pulling the gasses out or a combination of both.

And the main concern is, if it is a combination, does running the discharge to atmosphere change the dynamic and could this in any way be related to the sumping issue? I also have to assume the system is designed to handle a specific amount of blow by. Could changing components and increasing piston size, reducing intake resistance etc. be related to the sumping issue.

And for the record, I have a 17 SGS and have not had any sumping or transfer issues in 10000 mile and want to keep it that way.

 

interesting .

 

about all I can offer is on this issue is that after we updated the SE High Flow AC breather tubes to their reconfigured ones that reposition them into the intake further the excessive combustion residue has made its way into the intake more effectively as it is designed to, instead of dripping down the backplate and onto the filter causing external messes. some folks can't tolerate this epa design and opt to use a catch can or vent to the atmosphere but I don't believe it's a significant enough amount to cause engine problems

 

And the main concern is, if it is a combination, to make the discharge into the atmosphere change the dynamics and this could somehow be related to the matter of sum?

 

I agree. I have yet to see a single engine failure or any other mechanical issue attributed to the intake breathing oil mist from the breathers. Yeah yeah, some folks will point to it causing the tops of the pistols to become ugly... Okay, what is that hurting??? To me it's a fix to a non-issue. Unless of course, it's dripping onto your engine and streaming down the side. I can understand that. Mine doesn't so I see zero benefit in doing a breather mod.

 

My understanding is that the breather system is used to remove the accumulated pressure due to blowing. What I do not know is whether the pressure in the sump pushes all the gases out or whether there is a vacuum created since the exhaust pipe is in the inlet pulling the gases out or a combination of both. are related to the summation question?

 

How does the exhaust create a vacuum when it's not connected to the intake or crankcase? It's my understanding that the pressure being vented from the crankcase via the breathers is from the pistons moving up and down. The exhaust is pushed out of the combustion chamber when the piston moves into it's up-stroke.

 

think PCV..allowing pressure build up an escape route is all

 

Is the gas released by the oil tank cap (with breather) the same gas that is released by the breather of the air filter?

 

Pistons moving up and down create the pressure/vacuum in the crankcase. There is also a bit of blow by that contains unburned fuels that is bad for the environment, thats why they stopped venting them to the atmosphere some 30 years ago. Every street legal vehicle has the same system.