Ways The Oil Can Enter The Cooling System?

[hendrixgr]

I have a question that is bugging me for a long time, it is more of a theoretical question as my engine is working fine now.
When i had a blown head gasket tan colored oil sludge accumulated in the cooling system but not the opposite, i saw the head gasket and it was blown at cylinder #3 so combustion gasses were finding their way in to the cooling system.
My question is:
The Hayabusa transfers oil to the head externally and not through the head, i wasn't burning any oil so
how the oil found it's way to the cooling circuit?
Where in a normal engine the oil can enter the coolīng system?
Thanks in advance for your time.
Chis

 

[RedBull]

 

[hendrixgr]

I found the problem, here is the post

Oil Sludge In The Radiator And Hoses (solved) | Turbo

Hi. for at least 6 months i had a problem with my bike where oil sludge was detected inside the radiator water circuit, not much but enough to cause problems with the stock hoses. I thought that this might mean another blown head gasket but there where no air bubbles in the overflow tank like...

www.hayabusa.org

No it was not my wife....
Chris

 

[Danobusa]

Consider this......how does the engine oil return from the head to the pan?

 

[RedBull]

I found the problem ,
here is the post . . .

Oil Sludge In The Radiator And Hoses (solved) | Turbo

Hi. for at least 6 months i had a problem with my bike where oil sludge was detected inside the radiator water circuit, not much but enough to cause problems with the stock hoses. I thought that this might mean another blown head gasket but there where no air bubbles in the overflow tank like...

www.hayabusa.org

No it was
not my wife .

Chris

 

[hendrixgr]

By gravity as i found out, the cylinder block does not have any oilways AFAIK.
Chris

 

[202mphbusa]

By gravity as i found out, the cylinder block does not have any oilways AFAIK.
Chris

Correct oil hoses fed the top end gravity returns