Vacupan (air pump) check valves and breathers

bigblockmark · 2025-09-28T13:02:06-0400

The early GM engines that used a A.I.R. pump (1970 and later) had check valves at the manifolds. It is what is used as part of the race car header/valve cover vacupan systems. Anyone got a part number that has a reasonable price that local parts stores can order? There were 2 sizes. The one that fits 5/8" hose and 1/2" female pipe thread is the one.

Also, the valve cover breathers that are used, part number?

POWERSTROKE · 2025-09-28T13:12:41-0400

something like this?

CRANKCASE EVAC. SYSTEM

Crankcase Evacuation System

www.moroso.com

bigblockmark · 2025-09-28T15:13:49-0400

Thank you. I already have the full system. I am looking for replacement parts without having to buy the complete kit all over again. Couple cars have check valves that do not check anymore and breathers that leak.

Chevelle-Guy · 2025-09-28T18:13:19-0400

They show the individual parts too. 🤷🏻‍♂️

POWERSTROKE · 2025-09-28T15:20:43-0400

Rock Auto sells individual check valves. Not sure on thread pitch or hose sizes with these.

https://shorturl.at/t79mp

POWERSTROKE · 2025-09-28T15:25:37-0400

Pretty sure all the mfgs used these same check valves in the smog pump era.

scott foxwell · 2025-09-28T15:46:40-0400

They're called anti-backfire valves.

juiced coupe 78 · 2025-09-28T18:22:52-0400

These are what I used.

Damn, they have jumped in price. However, they are generally considered to be one of the best.

https://www.napaonline.com/en/p/CRB229000?srsltid=AfmBOor8xfyWP4KkjOizF91wkc5km1dny-2J7uYzuMQTtwbHZDVcU99B

bigblockmark · 2025-09-28T18:28:01-0400

Thanks guys. A 1/2" pipe nipple is $3 at Rural King. Cut it at a 45 degree angle and notch it and ready to weld in. Those do not usually need replacing. The check/backfire valve at OEM parts stores are probably cheaper than $30 if I can get a good number to work with. But counter guys and gals do not seem to find them in their computers.

The Echlin CRB 229000 is a 3/4' hose size. Most breathers hose size are 5/8". Need a number for the 5/8" hose check valve.

Econo Dragster · 2025-09-28T18:33:23-0400

The breathers are 70's to 90's Chrysler items. Early ones were black and a complete cylinder and the later ones were silver and stepped like the pic in post 2.

mrdragster1970 · 2025-09-29T16:56:16-0400

Econo Dragster said:
The breathers are 70's to 90's Chrysler items.
Early ones were black and a complete cylinder and the later ones were silver and stepped like the pic in post 2.

That's what we used in the day.
Mopar parts.

.

POWERSTROKE · 2025-09-28T18:41:01-0400

AC Delco # 19307616 $16.32 ea. Rock Auto 🤷‍♂️

bigblockmark · 2025-09-28T19:27:51-0400

The notch is like a venturi in a carburetor. Supposed to increase the signal.

bigblockmark · 2025-09-28T19:36:19-0400

Summit has 19307616 in stock $21. Not sure what hose size. 5/8" or 3/4"? Rock Auto at $16 as above.

bigblockmark · 2025-10-01T15:20:31-0400

Car Quest Auto Parts here in town got me a 5/8" hose x 1/2" NPT female thread A.I.R check valve CRC1001. $32 with tax. Next time I will get Summit for less, but not as cheap as Rock Auto.

Vacupan (air pump) check valves and breathers

CRANKCASE EVAC. SYSTEM

Top Contributors this Month

Recommended Communities