Yes. The red arrow is pointing at the Leather seals. When you order new seals they come with complete instructions and diagrams. I am happy to report that in 20 years no one has told me that they couldn’t make the primer work with a new set of seals.
To check the one way check valve, clean it off so you don’t get junk in your mouth, Then put the end with the hole up to your lips. When you blow air should not pass. When you suck ,air should pass freely. If not the little stainless steel ball inside is stuck from old varnish. Soak the valve in Acetone and or lacquer thinner and blast it out with compressed air until it functions as described above.
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