OCC lines collapsing

The_big_dill

Greenie N00B Member
Finally installed my mishimoto OCC with custom bracket and cheapo coolant hoses and am seeing some hoses collapse during idle. Logically speaking, it makes sense, but wanted to confirm with someone experienced with OCCs.

PERM PCV plate -> PCV Valve (orange half) -> (Green half of PCV valve) to IN port of OCC.
OUT port of OCC -> Check valve (pointing towards intake) -> Intake manifold PCV input bung.

The PCV valve and Check valve are mounted very close to the OCC.

When idling the hose between the PCV valve and OCC as well as the hose between the OCC and the intake manifold are collapsing, probably due to cheap hoses and strong Vacuum.

Any concerns with driving it like this until I get better hoses?

Worst thing I can imagine is the crank pressure isn't being evacuated properly.
 
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Crank pressure can do very bad things to engine seals and can lead to leaks, not to mention long term oil contamination.

Long story short, buy some better hoses.
 
Straight to the point with a solution. Thanks Johnny! Now I know the push on style listings.

Unfortunately majority won't ship to Canada. Those that do charge ~$20 just to ship a foot. :\ Rockauto has PCV hose for around $1/foot but shipping for the 25' reel is close to $80! I will keep looking.

I did some more thinking and I imagine I am building quite a bit of pressure in the crankcase with the hoses collapsing.
 
Thanks for the replies guys!

Crisis averted. I found someone local that would sell me braided line that fit. Everything else I would have to buy in bulk of 25'+
 
Crank pressure can do very bad things to engine seals and can lead to leaks, not to mention long term oil contamination.

Long story short, buy some better hoses.

Missed this message, sorry.

Thanks for chiming in, The shop where I work on the car is 30 mins from my house. I am spoiled with a hoist and wasn't sure if I should risk driving it back to the shop with the hoses.

I ended up carefully driving it to the shop anyways, shutting car down when I car to relieve some pressure.

As an OCC is a very healthy mod for the engine, it can also be dangerous. Not sure how you would check its function beyond seeing oil drained out the OCC. I removed my oil cap while engine is running and I feel pulses of pressure out of it, likely normal, but I am wondering if these engines normally push pressure out the cap?
 
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Missed this message, sorry.

Thanks for chiming in, The shop where I work on the car is 30 mins from my house. I am spoiled with a hoist and wasn't sure if I should risk driving it back to the shop with the hoses.

I ended up carefully driving it to the shop anyways, shutting car down when I car to relieve some pressure.

As an OCC is a very healthy mod for the engine, it can also be dangerous. Not sure how you would check its function beyond seeing oil drained out the OCC. I removed my oil cap while engine is running and I feel pulses of pressure out of it, likely normal, but I am wondering if these engines normally push pressure out the cap?
Yes they will and you will get a mist of oil spraying out if you leave the cap off which has enough force to hit the under side of the hood. "ask me how I know"
 
Yes they will and you will get a mist of oil spraying out if you leave the cap off which has enough force to hit the under side of the hood. "ask me how I know"
Haha. I remember doing an oil change on my Protege5 and couldn't figure out why my car smelled like burning oil for the whole trip to work and back. At first I thought I spilled oil on the exhaust manifold, but turns out I was just rust proofing my entire engine bay without the oil cap! :)
 
You forget to put the cap on once during an oil change when you're checking levels and you learn the spray oil pretty good...saw a "friend" do it lol. So yeah cars normally shoot out the oil cap don't be taking that off while it's running
 
You forget to put the cap on once during an oil change when you're checking levels and you learn the spray oil pretty good...saw a "friend" do it lol. So yeah cars normally shoot out the oil cap don't be taking that off while it's running

Was simply using it to check how much pressure there might be in the crankcase, but i guess thats inconclusive.
 
Could collapsed occ lines cause a rich at idle state ? Currently under going same issue where lines are collapsing on both in & out ports
 
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