how can fuel get into the oil?

[rag231]

I came up with bad rings or very worn valve guides, any other suggestions. Thanks.

 

[KevinB]

I came up with bad rings or very worn valve guides, any other suggestions. Thanks.

PCV system not working properly is another.

 

[BuickTim]

A leaking injector after shutdown will also put fuel in oil.

 

[pacecarta]

so will running an overly rich tune

 

[blackmonte]

I am guessing with a fat tune 100% e85 same thing?

 

[pacecarta]

if the mixture is rich (rich is relative to the fuel being used and its stioch ) it doesnt burn completely the unburnt fuel has to go somewhere , when you can smell it at the tailpipe its way over rich the bulk of the fuel falls victim to gravity and cylinder pressure will push it to the cylinder rings where it will wash off and mix with the oil film on cylinder walls and end up in the pan


poor tune , worn rings , stuck-faulty- bad spraying injectors , bad o2 sensor ,weak ignition ,bad wires (misfires), too much fuel pressure , bad ecm coolant sensor ,bad maf , header or exhaust leaks , wrong chip for injectors
, running less boost than chip designed for ...all can lead to rich mixture and fuel in the oil

with a scantool like scanmaster (even better data with a DS or powerlogger)you can keep an eye on blms , o2 readings , clt temp ,maf reading and avoid problems before they get out of hand ,

 

[dr_frankenstein]

a poorly assembled engine will do this upon start up if the rings and pistons were overly lubed prior to installation. The result is a glazed cylinder at start up. and a ruined engine down the line.

A.j.

 

[XLR8]

I had a stuck-open stock injector cause that problem back in '88.