Engine/Crankcase Breathers

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Jacob789456

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Hi all,
I am in the final stages of my jeep project and the last thing I am stuck on is trying to figure out where the crankcase breather hoses go. Do they even have hoses? I am talking about the hose barb looking things on the back of each valve cover right behind the last spark plugs. If they have hoses I cannot find a place that they would connect into. My intake system does not have the resonator box, it just has the straight pipe and elbow to the throttle body that apparently came with some 3.7's because it says "Jeep" and "3.7 V6" on it. Also the air filter box has some sort of sponge inside with a little hose connector on the exterior of the box. Thanks for any help!
 

jnaut

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Hi all,
I am in the final stages of my jeep project and the last thing I am stuck on is trying to figure out where the crankcase breather hoses go. Do they even have hoses? I am talking about the hose barb looking things on the back of each valve cover right behind the last spark plugs. If they have hoses I cannot find a place that they would connect into. My intake system does not have the resonator box, it just has the straight pipe and elbow to the throttle body that apparently came with some 3.7's because it says "Jeep" and "3.7 V6" on it. Also the air filter box has some sort of sponge inside with a little hose connector on the exterior of the box. Thanks for any help!

The sponge inside the airbox with the hose is the PCV valve hose.

The manual suggests there are breather hoses for the engine:

The cylinder head covers (Fig. 16)(1,2) are made of
glass re-enforced thermoset plastic, and are not interchangable
from side-to-side.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the resonator assemble and air inlet
hose.
(3) Disconnect injector connectors and un-clip the
injector harness.
(4) Route injector harness in front of cylinder head
cover.
(5) Disconnect the left side breather tube and
remove the breather tub


I wish I could give you more exacting information. There are some really knowledgable folks here who can probably help you more.
 

mmc757

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That barb fitting on the air box is where they go. They come together at a tee first, then join the PCV line, then enter the air box.
 

DadOSix

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That barb fitting on the air box is where they go. They come together at a tee first, then join the PCV line, then enter the air box.
^ this.

each pcv attaches to a defunct plastic tubing, so you can do it with hose. Left side engine has an elbow, comes fwd and crosses to the right side, just in front of the throttle body. A tee overtop the right valve cover - back to right pcv - forward to airbox. Airbox has / needs a foam/fiber element. There is no direct one anymore. My local autozone rep showed me his breather elements and i picked the closest thing.
 

duderz7

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If you need a new sponge bob (as they're called around here) in your airbox, they're quite easy and cheap to replicate out of a lawnmower air filter, just cut to shape. Mine had been lost sometime before I owned it and someone had put what looked like pink fiberglass insulation, it was nasty.
 

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