Oil catch cans are they needed?

If the canister got full then wouldn't any additional oil just get sucked into the engine just as if there was no canister?

HotLap said:

Bob, my thoughts as well...except if the canister was full it might suck liquid oil into the intake? Not sure if the oil could make it through the catch can filters or not...would like to know how For Performance addressed this...

Click to expand...

I have a Ford can on the passenger side and on it the crankcase inlet is lower than the outlet that connects to the engine air intake so if it fills up the overflow would just run back into the valve cover. On the JTL (on the drivers side of mine) both hoses are at the same level so as you said it's likely the engine will gulp oil through the intake manifold. Likely there would be periodic or maybe steady blue exhaust smoke. I know now I'll definitely be checking the JTL can more frequently from now on.

brad said:

Is the purpose of those cans to keep us from having to clean oil residue out of the intake? If this is a critical problem, wouldn't there be a simple black plastic can installed from the factory and the owner's manual would say empty it at every oil change?

I am seeking knowledge here, not commenting on those who have installed them.

Click to expand...

Yes, it is to keep the oil mist from entering the intake system. I believe the passenger side outlet dumps into the intake manifold after the throttle body and the drivers side dumps into the air intake just before (or maybe just after) the throttle body. Once the inside of the intake is coated with oil cleaning it would be big $$$.

As to why Ford didn't put the on in the factory I'm speculating that it might have to do with meeting emission requirements but someone more knowledgable than me may have better insight into this.

I suspect that without positive crankcase ventilation you might have issues such as failure of the crank seals.

HotLap said:

To report back on my JLT (passenger side) oil catch can. I just checked it yesterday and after approx. 400 miles the can was about 20% filled. While I didn't expect that much oil with only 400 miles, very happy that's not being sucked back into the intake/valves/combustion chamber. The car doesn't appear to be burning any oil (I have about 900 miles on it to date) as the oil level is still showing right at full.

Click to expand...

Roughly the same experience with my pass side JLT.

Lex said:

I recently purchased both driver/passenger side cans, but only installed passenger. My concern is making an already hard task of checking oil levels that much more difficult.

For those of you who have the driver side installed, can you share your dipstick removal/check/insertion method. Not much room behind the shock tower brace and with a hot engine...I really dont want to burn my hand.

Looking forward to learning from you. Thanks!

Click to expand...

Mine was a bit challenging at first but you’ll get the hang of it pretty quick. Just use a glove on your right hand and you’ll be fine