PCV manifold or ported vacuum?

[Johnny Atomic]

Stupid question. Does the PCV go to manifold or ported vacuum?

 

[Johnny Atomic]

Currently it goes from #2 to a T and then to PCV

You must be registered for see images attach

 

[fast 99]

2 is PCV vacuum, hose on T should go to charcoal cannister.

 

[Johnny Atomic]

2 is PCV vacuum, hose on T should go to charcoal cannister.

Great, that's how it is. Could bad PCV valve cause massive oil consumption.

 

[fast 99]

If baffle is missing in valve cover yes, otherwise no.

If oil consumption started rather quickly could be intake gasket leaking on the bottom. There is a procedure to diagnose that.

 

[sidschev]

where does 4 go

 

[75gmck25]

What is the number on the side of your Quadrajet? Mine is a 1980 model, and it does not have that #4 connection.

PCV hose definitely does not go to the charcoal canister, but it is possible that the canister vent is T’d into the PCV line.

PCV hose is connected to a 3/8” fitting on the carburetor base plate, and the hose runs over to the PCV that is inserted into a grommet in the driver’s side valve cover. On the passenger side valve cover there is another hose fitting, and that hose runs up to a fitting on the air cleaner body. If someone switched to an aftermarket air cleaner, they may have a breather vent cap instead of the hose to the air cleaner.

PCV fitting on the carburetor sucks air from the crankcase (valve cover fitting) into the base of the carburetor when the PCV valve is open. Air then enters the crankcase through the breather in the other valve cover, so you are sucking air through the crankcase and removing moisture. It also prevents excess pressure from blowby in the crankcase.

 

[fast 99]

PCV hose definitely does not go to the charcoal canister, but it is possible that the canister vent is T’d into the PCV line.

Hose from T goes to charcoal cannister and may have additional vacuum supply to charcoal cannister at PCV itself. There are so many iterations depending on options, GVW, motor and year really need a vacuum diagram for the specific application. Available on this site.

 

[Johnny Atomic]

If baffle is missing in valve cover yes, otherwise no.

If oil consumption started rather quickly could be intake gasket leaking on the bottom. There is a procedure to diagnose that.

Thank you. Yes the smoking seemed to start after I had the valve seals replaced.

Where is that procedure???

 

[Johnny Atomic]

What is the number on the side of your Quadrajet? Mine is a 1980 model, and it does not have that #4 connection.

PCV hose definitely does not go to the charcoal canister, but it is possible that the canister vent is T’d into the PCV line.

PCV hose is connected to a 3/8” fitting on the carburetor base plate, and the hose runs over to the PCV that is inserted into a grommet in the driver’s side valve cover. On the passenger side valve cover there is another hose fitting, and that hose runs up to a fitting on the air cleaner body. If someone switched to an aftermarket air cleaner, they may have a breather vent cap instead of the hose to the air cleaner.

PCV fitting on the carburetor sucks air from the crankcase (valve cover fitting) into the base of the carburetor when the PCV valve is open. Air then enters the crankcase through the breather in the other valve cover, so you are sucking air through the crankcase and removing moisture. It also prevents excess pressure from blowby in the crankcase.

carb number 17083442.

Here is a photo of the vacuum diagram under my hood. It shows a hose from carb to T and one side of T goes to PCV, other side goes to Decel Valve (whatever that is), and small fitting on top of PCV valve goes to cannister.

 

[fast 99]

carb number 17083442.

Here is a photo of the vacuum diagram under my hood. It shows a hose from carb to T and one side of T goes to PCV, other side goes to Decel Valve (whatever that is), and small fitting on top of PCV valve goes to cannister.

Like I said there are lots of designs. Your is different than picture I added.

Checking for intake leak involves plugging all the engine vents to see if engine crankcase goes into vacuum.

Plug PCV valve cover hole and make sure oil fill cap seals. With engine running lay your hand over the breather vent on the other side. Hold it there for 10 seconds or enough time to determine pressure or vacuum. If vacuum is present intake is leaking. If pressure is felt intake gasket is likely ok.