(Advice) PCV Valve strange issue.

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Laqota

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So I have an 1983 Chevy C10 I bought from my grandpa.

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This recently started happening but the thing started vaping. I had to send it to its room and stuff and ground it for 3 months.

My oil pressure would drop when I ran the engine. I would take, wipe, and check my dipstick and almost all the oil was gone so I was thinking it was a head gasket leak. Right as I was ready to take apart the engine starting with valve cover I took out the PCV valve first. It was clean, still raddled, but when I took the tube off oil leaked all over. It had been drinking my oil straight from my PCV valve like a straw.

The look of the PCV valve was good. It Isn't rusty, isn't damaged. It raddles but it's allowing the engine to suck oil into my carbuerator. Should I replace it?
 

fast 99

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Gat an AC Delco or GM PCV. Have seen that many times. Rattling PCV will not flow as designed either.

A replacement PCV will not fix the oil use. Is the baffle in place? Excessive blow by?
 

Laqota

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1. What is a baffle.
2. I'm not sure how to test excessive blow by.
 

Ricko1966

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1. What is a baffle.
2. I'm not sure how to test excessive blow by.
The valve cover on the left,bottom 1/3 of the valve cover. That is a baffle,it's kind of like a sheet metal box below the pcv valve. It is not air tight but it prevents the pcv valve from having completely unrestricted access to the crankcase vapors and oil splash. Blow by is too open to the viewers discretion, it's the amount of pressure that blows by the rings and if you've got the oil cap off you can see how much it's venting. But if you don't know what normal looks like you won't know what excessive looks like. Run a compression test. How low on oil does it get? In how many miles?
 

Laqota

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Oh yeah. The Baffle is there. I didn't know what you meant lol. I ran the truck with the vacuum tube from the Carb > PCV off and plugged the carb with my finger (to stop vacuum leak while running). Nothing comes out of PCV it's only when it's got suction from the carbuerator that it sucks oil real bad. Like to the point where if I take the Vacuum tube off the PCV valve after a run oil drains out of the Tube. I have an edelbrock 1406.
 

Ricko1966

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Oh yeah. The Baffle is there. I didn't know what you meant lol. I ran the truck with the vacuum tube from the Carb > PCV off and plugged the carb with my finger (to stop vacuum leak while running). Nothing comes out of PCV it's only when it's got suction from the carbuerator that it sucks oil real bad. Like to the point where if I take the Vacuum tube off the PCV valve after a run oil drains out of the Tube. I have an edelbrock 1406.
Change the PCV valve,but somethings not right you shouldn't have that much oil vapor in a very short time. The PCV valve doesn't touch the oil only the vapor that gets past the baffle. That's why I asked how low does it get,in how many miles. Also still run compression check so we can get an idea what kind of shape the rings are in.
 

Laqota

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I ran it about 10 minutes or so. I think what I was looking at was the hole the PCV goes in. Is that the baffle? If your talking about something in the valve cover I'll have to take it off tomorrow and check. I'll need to rent a compression tester unless i got one.

Honestly. Could I just use a flashlight to look down in there. Wouldn't I just see the valves If I didn't have one lol
 
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Old Guy Bill

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What kind of valve covers are these? Are they the stock equipment?
The other valve cover, the one without the PCV valve, must have an opening for air to enter the engine….
Give us some pics!!
 

Laqota

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I replaced the PCV valve and it stopped drinking oil from the PCV. I did had a baffle, but for some reason the other one was just having enough suction to suck oil up. Nothing was replaced on this truck since 1983. It was not taken care of very well. I still have the ongoing issue of coolant and oil leaking in to the combustion chamber once the engine heats up, because my gaskets are MUSH. But besides that, at least it wont be ruining the carburetor I got!

Yeah, now it doesn't drink oil on startup, it just drinks oil when it's heated up because of the bad gaskets (im replacing soon). Which I prefer a lot more. I still haven't ran a compression test since I need to find one.
 
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JBswth

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I replaced the PCV valve and it stopped drinking oil from the PCV. I did had a baffle, but for some reason the other one was just having enough suction to suck oil up. Nothing was replaced on this truck since 1983. It was not taken care of very well. I still have the ongoing issue of coolant and oil leaking in to the combustion chamber once the engine heats up, because my gaskets are MUSH. But besides that, at least it wont be ruining the carburetor I got!

Yeah, now it doesn't drink oil on startup, it just drinks oil when it's heated up because of the bad gaskets (im replacing soon). Which I prefer a lot more. I still haven't ran a compression test since I need to find one.
Better replace those head gaskets right away. Coolant in the engine oil is bad, as when hot, it leaves a gritty residue in the oil and causes bad wear, as it is an abrasive.

J. B.
 

Laqota

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Better replace those head gaskets right away. Coolant in the engine oil is bad, as when hot, it leaves a gritty residue in the oil and causes bad wear, as it is an abrasive.

J. B.
The weird thing is I'm getting coolant blowing out of the side of my block on the passenger side, and coolant in my combustion (since the exhaust smells sweet, and is blowing white smoke). But currently, my engine oil still has not been affected. I was thinking it was my intake gasket (believe it or not. Was redone about 4 years ago), but I was just thinking of replacing them both (for my truck, it's about $64) since the truck is so old, and my grandpa used it since 2009, bought it from a guys forest, and drove it for work (painting in the MO area)
 

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