Aftermarket oil catch install advice

[fjs3]

Last week I installed an aftermarket oil catch can on my NA 2L to help keep blow-by gas from running into the intake. I test ran it for 30 minutes but found out that pressurized gas had caused the oil to spurt out of my oil cap. This was caused by the intake valves of the catch being too small—it was just 1/4" while the original on the valve cover and intake is 1/2". The image attached shows how I installed the can although it's not really working for now.

I uninstalled the hoses (took out one of the valves too as a sample) and returned the oem hose the solve the problem but I'm still keen on using the catch can. I'm going to replace the small valves with larger ones before running them through the engine again.

My question is, if the location of the can is too far from the engine? Since it's an NA, the fumes circulate only through the vacuum action of the engine. I'm not sure if the catch needs to be closer for it to work properly. Some advice would help. Thanks

 

[flash02]

Do you have a vent on the catch can, if not that is your problem.

 

[cody c]

Do you have a vent on the catch can, if not that is your problem.

His can vents gases to the air intake to burn them, venting the gasses to atmosphere instead kind of defeats the purpose of that.

It does sound like the ports are too small, but also maybe that you have a bit more pressure then you should, any chance youve checked your compression lately?

The easiset fix though as said above, would be to add a filter, though I would install larger fittings to the catch can or find a different one with bigger fittings first.

 

[fjs3]

His can vents gases to the air intake to burn them, venting the gasses to atmosphere instead kind of defeats the purpose of that.

It does sound like the ports are too small, but also maybe that you have a bit more pressure then you should, any chance youve checked your compression lately?

The easiset fix though as said above, would be to add a filter, though I would install larger fittings to the catch can or find a different one with bigger fittings first.

The compression is still fine. The engine isn't burning oil, overheating, or puffing out black smoke.

I'll try the larger fittings first because like you said, venting to atmosphere defeats the purpose of having a can in the first place. If it still doesn't work properly then I'll add a vent or just remove the whole thing.

 

[fjs3]

Finally got my catch can reinstalled over the weekend. The larger inlets did the trick and the engine's not getting any back pressure from the fumes anymore. I relocated the can closer to the engine so the fumes will circulate properly. Set-up looks good.