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Engine Hose from carb to valve cover is loose

Engine Hose from carb to valve cover is loose

Jride

Jeeper
Posts
25
Thanks
0
Location
New York
Vehicle(s)
1986 CJ7 Laredo. 4.2 liter, straight 6 cylinder
There's a hose that connects the carb to the valve cover - near the back of the engine / firewall. This hose fits really really lose. Is that OK? Or is it suppose to be tight to create some sort of vacuum? I am pointing to it in the attached photo. thanks!

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Parts stores usually have those in stock on one of the fix it aisles.
 
After looking at the engine agin more closely (and doing more research) I realize I misspoke on the connections and want to clarify something. The hose near the back of the valve cover (the one I'm pointing to in the original photo) goes into the bottom of the air filter that sits atop the carb. The hose at the front of the valve cover goes into (what i think is) the top of the intake manifold.

So i think the set up is:
Back hose = fresh air intake into crankcase (this is loose fitting)
Front hose = PCV return (this is nice and snug)

My questions:
1. Is it important for that fresh air intake hose to be snug with the valve? It's kinda loose right now
2. The PCV hose is connected to a small metal wired cylinder before continuing to the intake manifold. Any idea what this is? A sensor? (New photo attached)

Video explanation here

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That is the PC (positive crankcase) valve. It's used to evacuate gasses from the engine that are generated while running (blow-by). If you shake it in your hand you will feel a clunking. That is normal. If not, just get a new one.
 
So normally at the rear of the valve cover (where you were pointing in the first photo) should be a hose connection to a filter inside the air cleaner housing for fresh air to be "sucked" into the engine when the PCV valve opens. At the front of the valve cover should be the PCV valve which is then connected via a "tee" into manifold vacuum. Technically it really doesn't matter which is at the front and which is at the back of the valve cover other than hose routing and possible lengths. The other part of that "tee" goes to the purge port on the charcoal canister. When the PCV valve is open (the "rattling" moving part inside) engine vacuum via the manifold connection sucks in air and vapor mixture, which is comprised of vapors from engine blowby and fresh air via the other hose at the rear going to the air cleaner, through the valve cover. This same manifold vacuum connection is also purging vapors from the fuel tank as well (that "teed" connection at the charcoal canister). Here are a few shots of the stock hose routing for the PCV and related vacuum lines.

I think that device in the second photo is the EGR/canister Solenoid; but that device shouldn't be connected to the PCV/Purge port, it should be connected to the charcoal canister Purge Signal port. Check my third pic below. So I'm either wrong on what that is or you have a hose routing issue.

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