PCV Valve

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WendyB73Mach1

Member
Joined
Nov 1, 2024
Messages
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Location
Ontario Canada
My Car
1973 Mustang Mach 1
I have a 351C Q code I’m trouble shooting. Can you tell me where the PCV valve is? A picture would be amazing. I’m experiencing a gas smell from the engine compartment so I’d like to replace anything that may be responsible for this. Thanks!
 
The valve should be in the oil fill cap on the left valve cover. It should have a formed hose attached. If you smell gas, it is likely a leak at the carburetor or attaching hose section. Chuck
 
The valve should be in the oil fill cap on the left valve cover. It should have a formed hose attached. If you smell gas, it is likely a leak at the carburetor or attaching hose section. Chuck
This is my oil fill cap. I’m not sure that I see a valve or is it the entire elbow?
 

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You have some custom previous owner work done there. The PCV is likely in the opposite corner on the passenger side valve cover.
 
This is on the passenger side. Would this be the PCV valve and if so how do I remove it? Thanks again everyone.
 

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Here's the PVC valve on a couple of mine. Its just pushed down into the oil cap, on the driver's side valve cover. You just pull it straight out.

For a replacement, I like the ones that come off at 90 degrees like this. I wanna say its a GM part. The original ones for our cars were straight, and used a 90 degree hose. Its a little more compact if you use the PCV valve with its own 90 degree. And if you use a universal one, it may come with 2 ports and a cap that you put on one of them.

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This is my oil fill cap. I’m not sure that I see a valve or is it the entire elbow?
Yeah, this is where your PCV should be, in the cap. I can see from your picture that the rubber hose from your fill cap connects to a steel line that I assume goes to the back of your carb, with another short section of hose. That's the pcv line. I can't tell in your picture if your elbow in your oil fill cap has a valve in it or not, kinda looks like it's just an elbow without a valve. But this is where one would go, at least on my 73 Q-code. Here's pictures of mine.

The other picture you posted in your other "PCV Location" thread on your passenger side valve cover is just a vent line to a filter on the side of your air cleaner not for the PCV, as it doesn't go directly to the carb. I've also attached the Ford description of how all this works together. Note though, that this is showing a simplified 6 cylinder valve cover versus our V8.
 

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@WendyB73Mach1 - I merged your two threads, it's easier to follow along in a single thread, rather than multiple threads on the same subject.

The passenger side is the factory valve cover to air filter breather hose. Nothing wrong there.

Can you take a pic of the driver's side hose and tube setup with the air cleaner removed?

Regarding another thread you created about gas smell, that blue nipple sticking out the side of the air filter is for the vapor line. It's normally connected via a hose to the charcoal canister on the back of the passenger shock tower. That could easily be the source of the odors.
 
I just wanted to say a huge thank you to everyone who shared their insight and photos. I finally found my PCV valve about half way between the oil filler cap and the back of the carb. It has a larger hose on one side and a smaller diameter hose on the other. It’s certainly an unusual location for it, but I’m happy to finally know where it is and more importantly to learn what a helpful community I now belong to. Thanks everyone!

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