Surprisingly clean intake valves at 187k miles

[SHOZ]

Originally Posted By: VeryNoisyPoet
Originally Posted By: SHOZ
Put a catch can on it inline between the PCV valve and intake manifold to catch the oily vapors that make the crud.


Easier said than done because of the forced induction. PCV is sent either directly into manifold or into turbo inlet depending on operating conditions. Would take some hacking to get a system that behaves correctly in both modes (two catch cans?), and I'd have to deal with being CARB compliant because I may end up moving to California in the near future.

Good news is the factory PCV system does have a built-in oil separator that drains oil to the sump, and the intercooler has a weep hole that ejects some of the oil that makes it through the turbo.

It definitely could be better, though I'm not surprised at how much crud is there after two decades of use.
I have a turbo with two cans. There is a definite difference in what is collected. The turbo side is almost pure oil from the mist under he valve cover. The PCV is mostly gasoline and water. It's the gasoline and water that gets baked into the intake.

Here's a pic of a typical 5k catch can drain. The dark oil on top is from the turbo side, all the rest is from the PCV side.

 

[VeryNoisyPoet]

Originally Posted By: SHOZ
I have a turbo with two cans. There is a definite difference in what is collected. The turbo side is almost pure oil from the mist under he valve cover. The PCV is mostly gasoline and water. It's the gasoline and water that gets baked into the intake.

Here's a pic of a typical 5k catch can drain. The dark oil on top is from the turbo side, all the rest is from the PCV side.



Very interesting! Thanks for the info. I'd really want to try that, but things aren't looking good for passing CA smog because it modifies the PCV system.

"Don't move to inspection-crazy Cali" isn't an answer either, since that's where my girl lives and spending 11 months out of the year apart is not fun.

I may just have to deal with the manifold needing a clean every decade or so

 

[SHOZ]

Originally Posted By: VeryNoisyPoet
Originally Posted By: SHOZ
I have a turbo with two cans. There is a definite difference in what is collected. The turbo side is almost pure oil from the mist under he valve cover. The PCV is mostly gasoline and water. It's the gasoline and water that gets baked into the intake.

Here's a pic of a typical 5k catch can drain. The dark oil on top is from the turbo side, all the rest is from the PCV side.



Very interesting! Thanks for the info. I'd really want to try that, but things aren't looking good for passing CA smog because it modifies the PCV system.

"Don't move to inspection-crazy Cali" isn't an answer either, since that's where my girl lives and spending 11 months out of the year apart is not fun.

I may just have to deal with the manifold needing a clean every decade or so

Both my cans are out of sight. All you can see are some hoses.

 

[Trav]

The cleaners in the fuel are doing their job well, everything post injector is nice and clean pre injector where the fuel has no direct contact not so nice. A lower Noack oil may help.