Moroso 85469 Dual -12AN Aluminum Breather Tank Catch Can

Why Use a Remote Breather Tank?

Crankcase gases contain more than air.

Blow-by can carry:

• Oil mist
• Fuel vapor
• Moisture
• Combustion byproducts

Simply venting that mixture through open valve-cover breathers can allow oil mist to collect around the engine compartment.

A remote breather tank moves the venting and separation function away from the engine.

A typical racing arrangement becomes:

CRANKCASE → -12AN HOSE → BREATHER TANK → FILTERED ATMOSPHERIC VENT

Oil mist entering the tank is encouraged to separate from the airflow and remain inside the container.

The tank can then be drained during routine service.

Internal Oil Separation

A breather tank needs to do more than provide an empty aluminum container with a filter on top.

Its job is to reduce the amount of oil mist reaching the breather element.

Moroso uses internal separation features to encourage suspended oil to drop out of the airflow and remain in the tank.

That’s important because an oil-saturated breather filter can:

• Restrict ventilation
• Become messy
• Allow oil to escape
• Reduce effective crankcase breathing

The tank provides volume and separation before the gases reach the breather element.

Filtered Clamp-On Breather

Moroso includes a non-hooded clamp-on filtered breather.

The breather allows air to escape while helping trap residual oil mist.

Moroso lists its 68815 non-hooded filtered breather as the replacement component for this tank.

That means the filter element is serviceable rather than being a permanent part of the tank.

Inspect it regularly, particularly on engines producing significant blow-by.

Bottom Drain

Collected oil and condensation need somewhere to go.

The Moroso 85469 incorporates a bottom drain arrangement so accumulated fluid can be removed during routine maintenance.

Moroso lists the 97200 ball valve among the replacement/service components associated with the tank.

How frequently the tank needs to be drained depends heavily on the engine.

A healthy race engine may accumulate relatively little fluid.

An engine producing substantial blow-by may fill the tank much faster.

Watch What Comes Out of the Tank

The contents of a breather tank can tell you something about engine condition.

Pay attention to:

• Oil volume
• Fuel smell
• Water contamination
• Sudden changes in collection rate

A major increase in collected oil may indicate:

• Increased blow-by
• Ring-seal problems
• Excessive oil reaching the breather pickup
• Poor valve-cover baffling
• Vacuum-system issues

The catch tank shouldn’t simply be emptied without ever asking why its behavior changed.

Lightweight Aluminum Construction

Moroso manufactures the 85469 from aluminum to keep weight reasonable while providing a durable tank for competition environments.

The standard 85469 uses a raw aluminum finish.

That distinguishes it from the closely related Moroso 85753, which provides a dual -12AN configuration with a black powder-coated finish.

For builders who prefer a natural fabricated-aluminum appearance, the 85469 is the straightforward choice.

Moroso 85469 vs 85753

These two tanks are closely related and should be merchandised together.

Moroso 85469

Inlets: Dual -12AN male
Finish: Raw aluminum

Moroso 85753

Inlets: Dual -12AN male
Finish: Black powder coat

The primary purchasing difference is finish.

A raw aluminum engine bay may look better with the 85469, while a build using black valve covers, hoses and accessories may favor the 85753.

3-1/8-Inch Tank Diameter

Moroso specifies the 85469 tank at 3-1/8 inches in diameter.

That relatively narrow body helps the tank fit into crowded racing engine compartments.

But diameter isn’t the only measurement that matters.

The filter increases the total installed height substantially.

6-1/2-Inch Tank Height

The aluminum tank itself measures approximately 6-1/2 inches high without the filter.

Use that measurement when evaluating mounting locations around:

• Inner fenders
• Firewall
• Radiator support
• Roll cage
• Engine plate
• Dry-sump tank
• Vacuum pump
• Accessory drives

Leave enough space underneath to access the drain.

11-1/2-Inch Overall Height

With the filtered breather installed, Moroso lists the overall height at 11-1/2 inches.

That’s the measurement that matters most when checking vertical clearance.

Don’t design the mounting location around the 6-1/2-inch tank body and then discover the breather filter wants to occupy the same space as the hood.

Mounting Hardware Included

Moroso supplies mounting hardware with the 85469 to simplify installation.

The tank should be mounted securely to a structural surface.

Avoid attaching it to thin sheet metal that allows the tank to vibrate excessively.

Remember that the tank becomes heavier as it collects fluid.

It also has large -12AN hoses attached to it, which can transfer additional loads into the mounting point.

Mount the Tank Vertically

A breather tank generally works best when installed upright.

That allows separated oil to collect at the bottom while gases continue upward toward the filtered vent.

Vertical mounting also keeps accumulated fluid near the drain.

Position the tank where the breather remains accessible for inspection and replacement.

Don’t Mount It Near Extreme Heat

Keep the breather tank and hoses away from excessive exhaust heat.

Avoid placing it directly beside:

• Headers
• Turbocharger turbine housings
• Downpipes
• Exhaust manifolds

Heat can degrade hoses and unnecessarily increase the temperature of the collected oil and vapor.

If proximity to exhaust components is unavoidable, use appropriate thermal protection.

Excellent for Dual Valve-Cover Venting

One of the most straightforward uses for the 85469 is a dual valve-cover breather system.

A large-displacement racing engine may use one -12AN connection from each valve cover.

The opposing fittings on the 85469 make this arrangement particularly clean.

The layout becomes:

LEFT VALVE COVER ↘

** MOROSO 85469 → FILTERED VENT**

RIGHT VALVE COVER ↗

This allows both cylinder-bank areas to breathe into one remote tank.

Valve-Cover Baffling Still Matters

Large -12AN fittings don’t eliminate the need for proper valve-cover baffling.

If the breather connection sits directly in heavy oil splash from the valvetrain, the hose can carry excessive liquid oil into the tank.

A properly baffled valve-cover fitting helps separate bulk oil before crankcase gases enter the hose.

This reduces the amount of oil the remote tank needs to handle.

Useful With External Vacuum Pumps

The Moroso 85469 is also useful with external racing vacuum-pump systems.

For example, the Moroso 22641 4-Vane Vacuum Pump actively evacuates crankcase gases from purpose-built racing engines.

In that type of installation, a breather/catch tank provides a controlled destination for the pump’s discharge.

The system may look like:

ENGINE CRANKCASE → VACUUM PUMP → BREATHER/CATCH TANK

The exact plumbing depends on the engine and vacuum-pump configuration.

Why Vacuum Pumps Need Oil Separation

A racing vacuum pump doesn’t move perfectly clean air.

The gases pulled from the crankcase can contain suspended oil.

Without proper separation, that oil can reach the discharge side and create a mess.

A remote breather tank allows oil mist to separate and collect while the gases vent through the filter.

That makes the tank an important supporting component rather than simply a decorative aluminum bottle.

Works With Wet-Sump Racing Engines

A wet-sump racing engine can use the 85469 as part of either a passive breather arrangement or an external vacuum-pump system.

The engine’s oil remains in the oil pan, while the remote tank handles crankcase ventilation.

A simple passive arrangement might use:

VALVE COVERS → -12AN HOSES → 85469

A vacuum-pump arrangement changes the routing according to the pump manufacturer’s requirements.

Useful With Dry-Sump Systems

Moroso also identifies remote breather tanks for use with dry-sump tanks.

Dry-sump systems move oil into an external reservoir and can carry a significant amount of entrained air.

The tank’s ventilation needs to be properly managed.

A remote breather tank gives that vented oil mist somewhere to separate rather than coating the surrounding engine compartment.

Dry-sump plumbing should always follow the tank and oil-system manufacturer’s specific recommendations.

Rear-End Vent Applications

Moroso also identifies the 85469 for applications such as rear-end ventilation.

A racing differential can generate internal pressure as the gear oil heats and expands.

A remote breather arrangement can move the vent point away from the housing while helping contain any oil carried through the vent line.

That’s especially useful in competition vehicles where fluid containment matters.

The tank’s dual connections also make it possible to collect from more than one compatible source when the system design allows it.

This Is Not a Typical Street Catch Can

The term catch can now covers a very broad range of products.

A small street-car oil separator installed between the PCV valve and intake manifold is fundamentally different from the Moroso 85469.

A conventional closed PCV catch can generally operates inside the engine’s emissions-controlled crankcase ventilation system.

The 85469 uses a filtered atmospheric breather.

Moroso explicitly states that the 85469 is:

Not legal for sale or use on pollution-controlled vehicles.

That’s an important distinction and should remain visible in the product description.

Racing Breather Tank vs PCV Catch Can

Street PCV Catch Can

Typically installed in a closed PCV circuit.

Its job is to separate oil from crankcase gases before those gases enter the intake.

Moroso 85469

A remote racing breather tank with an atmospheric filtered vent and large dual -12AN connections.

Its job is to collect oil mist while allowing crankcase or system gases to vent.

They may both collect oil.

That doesn’t make them interchangeable.

Universal Fitment

The Moroso 85469 should be classified as universal, not vehicle-specific.

Compatibility depends on the system being built rather than the vehicle’s year, make and model.

Important considerations include:

• Available mounting space
• -12AN hose compatibility
• Number of ventilation sources
• Crankcase configuration
• Vacuum-pump configuration
• Dry-sump layout
• Racing regulations

That makes a universal fitment classification much more accurate for ecommerce.

Not Legal for Pollution-Controlled Vehicles

Moroso explicitly marks the 85469 as not legal for sale or use on pollution-controlled vehicles.

That warning matters because the filtered breather vents to atmosphere.

Do not market the 85469 as a universal street-car PCV upgrade.

It is best positioned for racing and other appropriate competition applications.

Made in the USA

Moroso’s current USMCA documentation identifies part number 85469 as manufactured in the USA.

That’s a useful specification to include in the product data.

Moroso 85469 Specifications

Part Number: 85469

Product: Remote Breather Tank / Catch Can

Construction: Aluminum

Finish: Raw aluminum

Number of Inlets: Two

Fitting Size: Dual -12AN male

Fitting Position: 180 degrees apart

Tank Diameter: 3-1/8 inches

Tank Height Without Filter: 6-1/2 inches

Overall Height: 11-1/2 inches

Breather: Non-hooded clamp-on filtered breather

Mounting Hardware: Included

Drain: Bottom drain arrangement

Replacement Breather: Moroso 68815

Optional/Replacement Drain Valve: Moroso 97200

Fitment: Universal

Country of Origin: USA

Street/Emissions Status: Not legal for sale or use on pollution-controlled vehicles

About the Listed 1-Quart Capacity

Some reseller listings describe the Moroso 85469 as a 1-quart breather tank.

Moroso’s current 85469 product page does not specify a one-quart capacity.

For that reason, I would not use 1 Qt as a primary product specification unless you have separate current Moroso documentation confirming it.

Use Moroso’s published physical dimensions instead:

3-1/8-inch diameter

6-1/2-inch tank height

11-1/2-inch overall height

That avoids publishing an unverified capacity simply because it has propagated through marketplace listings.

Who Should Buy the Moroso 85469?

The Moroso 85469 makes sense for competition vehicles that need a high-flow remote breather with two large inlet connections.

Strong applications include:

• Drag cars
• Pro Street builds
• Race engines
• Dual valve-cover ventilation
• Vacuum-pump systems
• Wet-sump race engines
• Dry-sump systems
• Big Block Chevy race engines
• Small Block Chevy race engines
• High-output LS race engines
• Ford race engines
• Rear-end vent systems

It is particularly useful when two separate vent sources need to terminate at one lightweight remote tank.

Final Verdict

The Moroso 85469 Dual -12AN Aluminum Breather Tank is a straightforward racing solution for systems that need substantial ventilation capacity and oil-mist containment.

Its dual -12AN male fittings are positioned 180 degrees apart, simplifying large-hose routing from two sources, while the narrow aluminum body provides a compact remote collection point.

Moroso also includes the mounting hardware and filtered breather, with a drain arrangement at the bottom for routine servicing.

Most importantly, the 85469 shouldn’t be confused with a little street-car PCV catch can.

This is a large-line, atmosphere-vented racing breather tank designed for systems where moving air and separating oil matter more than fitting neatly between the windshield-washer bottle and factory airbox.

Give it good plumbing.

Give it proper baffling.

Mount it vertically.

And occasionally drain the thing.

Because discovering that your catch can is full only after it starts catching absolutely nothing is an unnecessarily traditional form of race-car maintenance.