Fuel / Carburetion System | Yamaha Outboard

What This Primer Bulb is Used For

A primer bulb is installed inline in an outboard fuel hose and acts as a manual fuel pump.

Squeezing and releasing the bulb draws fuel from the tank and pushes it toward the engine. Internal one-way check valves help keep fuel moving in the proper direction.

Primer bulbs are commonly used when:

• Starting an outboard after the fuel line has drained
• Priming a newly installed fuel-line assembly
• Refilling the line after fuel-system service
• Purging air from the fuel hose
• Replacing an old, hardened or damaged primer bulb

Compatible 3/8" Fuel Hose Options

Pro Marine stocks both Type A and Type B 3/8" marine fuel hose for use with the 8005 primer bulb.

3/8" Type B Marine Fuel Hose - 375

Bulk 3/8" Type B marine fuel hose for exposed and above-deck applications where Type B hose is appropriate.

Inside Diameter: 3/8"
Sold: By the Foot
Matching Clamp: Oetiker 4-185

View 3/8" Type B Fuel Hose

3/8" Type A Marine Fuel Hose - 375-1

Bulk Type A marine fuel hose for installations requiring the additional Type A fire-resistant classification.

Inside Diameter: 3/8"
Sold: By the Foot
Matching Clamp: Oetiker 4-185

View 3/8" Type A Fuel Hose

Correct Clamp for 3/8" Fuel Hose

Both the Type A and Type B 3/8" fuel hoses listed here use the same Oetiker 4-185 ear clamp.

Fuel Line Clamp and Installation Tools

Oetiker 4-185 Ear Clamp - 10 Pack

Matching clamp for both the 375 Type B and 375-1 Type A 3/8" marine fuel hoses.

View Oetiker 4-185 Clamp

Oetiker Standard Jaw Pincer Tool

Installation tool for properly closing Oetiker ear clamps on marine fuel-line connections.

View Oetiker Pincer Tool

Oetiker Clamp Pack with Tool

Complete assortment of commonly used Oetiker clamp sizes with the installation tool included.

A convenient option for marine shops, technicians and customers servicing multiple fuel-line sizes.

View Oetiker Clamp Pack

How a Primer Bulb Works

The primer bulb contains internal one-way check valves that control the direction of fuel flow.

As the bulb is squeezed and released, it draws fuel from the tank and moves it toward the engine. Repeated squeezes fill the hose and help purge air from the fuel line.

Primer Bulb Installation

Install the primer bulb with the fuel-flow arrow pointing toward the engine.

Secure the hose at the primer bulb and other barbed fittings using the correct Oetiker clamps.

When Should a Primer Bulb Be Replaced?

Fuel, heat, UV exposure and normal use can cause primer bulbs to deteriorate over time.

Inspect or replace the primer bulb if you notice:

• Cracking or visible deterioration
• A bulb that has become excessively hard
• A bulb that stays collapsed after squeezing
• A bulb that will not become firm while priming
• Fuel leakage around the bulb or fittings
• Air entering the fuel system
• Internal check-valve failure

Building a Complete 3/8" Outboard Fuel Line

Depending on the application, a complete 3/8" fuel-line setup may require:

• Pro Marine 8005 3/8" primer bulb
• 375 Type B or 375-1 Type A 3/8" fuel hose
• Correct tank-side fitting or connector
• Correct engine-side fitting or connector
• Oetiker 4-185 ear clamps
• Oetiker pincer installation tool

Type A or Type B Fuel Hose?

The Pro Marine 8005 primer bulb can be used with either listed hose because both use a 3/8" inside diameter.

Type B 375 is commonly used in exposed and above-deck applications where Type B hose is appropriate.

Type A 375-1 is used when the installation requires the additional Type A fire-resistant classification, including many enclosed and below-deck fuel-system applications.

Key Features

• Pro Marine 8005 marine primer bulb
• Designed for 3/8" ID marine fuel hose
• Compatible with 375 Type B fuel hose
• Compatible with 375-1 Type A fuel hose
• Used to manually prime outboard fuel systems
• Helps draw fuel from the tank toward the engine
• Both compatible hoses use Oetiker 4-185 clamps
• Oetiker pincer installation tool available
• Complete Oetiker clamp assortment with tool available

Need Help Building Your Marine Fuel Line?

Choosing the right marine fuel-line setup involves matching hose diameter, Type A or Type B classification, primer bulb size, fittings and the correct clamp.

Visit the Pro Marine Fuel Line Technical Center

FAQ

What size hose does the Pro Marine 8005 primer bulb fit?
The 8005 is designed for 3/8" ID fuel hose.

Can I use this primer bulb with Type B fuel hose?
Yes. It fits the 375 3/8" Type B fuel hose .

Can I use this primer bulb with Type A fuel hose?
Yes. It also fits the 375-1 3/8" Type A fuel hose .

Which clamp fits the 3/8" Type B hose?
Use the Oetiker 4-185 ear clamp .

Which clamp fits the 3/8" Type A hose?
The Type A hose also uses the Oetiker 4-185 ear clamp .

Do Type A and Type B 3/8" hose use the same clamp?
Yes. Both 3/8" hose options listed here use the Oetiker 4-185 clamp.

Which direction should the primer bulb be installed?
Install the primer bulb with the fuel-flow arrow pointing toward the engine.

What tool installs the Oetiker clamp?
Use the Oetiker Standard Jaw Pincer Tool .

Do you sell a clamp assortment?
Yes. The Oetiker Clamp Pack with Tool includes common clamp sizes and the installation tool.

Searchable Part Numbers & Terms

8005, Pro Marine 8005, 3/8 primer bulb, 3/8 marine primer bulb, outboard primer bulb, boat fuel primer bulb, marine fuel bulb, outboard fuel bulb, 3/8 fuel line, 3/8 outboard fuel hose, 375, 3/8 Type B fuel hose, 375-1, 3/8 Type A fuel hose, Oetiker 4-185, 4-185 fuel hose clamp, marine fuel line clamp, Oetiker fuel line clamp, primer bulb fuel line, marine fuel system, outboard fuel line, boat fuel line

What This Primer Bulb is Used For

A primer bulb is installed inline in an outboard fuel hose and acts as a manual fuel pump.

Squeezing the bulb draws fuel from the fuel tank and pushes it toward the engine. Internal check valves help direct fuel flow in the correct direction.

Primer bulbs are commonly used when:

• Starting an outboard after the fuel line has drained
• Priming a new fuel-line installation
• Refilling the line after fuel-system service
• Purging air from the fuel line
• Replacing an old, hardened or damaged primer bulb

Compatible Fuel Hose

Pro Marine stocks both Type A and Type B 1/4" marine fuel hose for use with this primer bulb.

MPI 1/4" Type B Marine Fuel Hose - 315-014

Bulk 1/4" marine fuel hose for exposed and above-deck applications where Type B hose is appropriate.

Inside Diameter: 1/4"
Sold: By the Foot
Matching Clamp: Oetiker 4-133

View 1/4" Type B Fuel Hose

MPI 1/4" Type A Marine Fuel Hose - 314-1

Bulk Type A marine fuel hose for installations requiring the additional Type A fire-resistant classification.

Inside Diameter: 1/4"
Sold: By the Foot
Matching Clamp: Oetiker 4-170

View 1/4" Type A Fuel Hose

Correct Clamp for Each 1/4" Fuel Hose

Both hoses use a 1/4" inside diameter, but their outside diameters are different because of their construction and wall thickness. This means they require different Oetiker clamps.

Fuel Line Clamps and Installation Tools

Oetiker 4-133 Ear Clamp - 10 Pack

Correct clamp for the MPI 315-014 1/4" Type B fuel hose.

View Oetiker 4-133 Clamp

Oetiker 4-170 Ear Clamp - 10 Pack

Correct clamp for the MPI 314-1 1/4" Type A fuel hose.

View Oetiker 4-170 Clamp

Oetiker Standard Jaw Pincer Tool

Installation tool for properly closing Oetiker ear clamps when assembling marine fuel-line connections.

View Oetiker Pincer Tool

Oetiker Clamp Pack with Tool

A complete assortment of commonly used Oetiker clamp sizes with the installation tool included.

A convenient option for marine shops, technicians or anyone servicing multiple fuel-hose sizes.

View Oetiker Clamp Pack

How a Primer Bulb Works

The primer bulb contains internal one-way check valves. When the bulb is squeezed and released, these valves allow fuel to move in one direction through the fuel line.

Repeatedly squeezing the bulb draws fuel from the tank, fills the line and supplies fuel toward the engine.

Primer Bulb Installation

Install the primer bulb with the fuel-flow arrow pointing toward the engine.

A typical fuel path is:

Secure each hose connection using the clamp matched to the specific fuel hose being installed.

When Should a Primer Bulb Be Replaced?

Primer bulbs are exposed to fuel, heat and the marine environment and can deteriorate over time.

Inspect or replace the primer bulb if you notice:

• Cracking or surface deterioration
• A bulb that has become excessively hard
• A bulb that stays collapsed
• A bulb that will not become firm when priming
• Fuel leakage around the bulb or fittings
• Air entering the fuel line
• Internal check-valve problems

Building a Complete 1/4" Outboard Fuel Line

Depending on your installation, a complete 1/4" fuel-line assembly may require:

• Pro Marine 8002 1/4" primer bulb
• 1/4" Type A or Type B marine fuel hose
• Correct engine-side connector or fitting
• Correct tank-side connector or fitting
• Correct Oetiker clamps for the selected hose
• Oetiker pincer tool

Type A or Type B Fuel Hose?

The primer bulb works with either of the 1/4" hose options because both have the same 1/4" inside diameter.

The correct hose classification depends on the fuel-system installation.

Type B is commonly used in exposed and above-deck installations where Type B hose is permitted.

Type A is used where the installation requires the additional Type A fire-resistant classification, including many enclosed and below-deck fuel-system applications.

Key Features

• Pro Marine 8002 marine primer bulb
• Designed for 1/4" ID marine fuel hose
• Compatible with MPI 315-014 Type B fuel hose
• Compatible with MPI 314-1 Type A fuel hose
• Used to manually prime outboard fuel systems
• Helps draw fuel from the tank toward the engine
• Type B Oetiker 4-133 clamps available
• Type A Oetiker 4-170 clamps available
• Oetiker installation pincer available
• Complete Oetiker clamp assortment with tool available

Need Help Building Your Marine Fuel Line?

Hose size, Type A or Type B classification, primer bulb size and clamp selection all need to match the fuel-system installation.

Visit the Pro Marine Fuel Line Technical Center

FAQ

What size hose does the Pro Marine 8002 primer bulb fit?
The 8002 is designed for 1/4" ID fuel hose.

Can I use this primer bulb with Type A fuel hose?
Yes. It can be used with the MPI 314-1 1/4" Type A hose .

Can I use it with Type B fuel hose?
Yes. It also fits the MPI 315-014 1/4" Type B hose .

Which clamp fits the 1/4" Type B hose?
Use the Oetiker 4-133 ear clamp .

Which clamp fits the 1/4" Type A hose?
Use the Oetiker 4-170 ear clamp .

Why do the Type A and Type B hoses use different clamps?
Both hoses have a 1/4" inside diameter, but their outside diameters differ because of their construction and wall thickness. Clamp size must match the outside diameter of the specific hose.

Which direction should the primer bulb be installed?
Install the primer bulb with the fuel-flow arrow pointing toward the engine.

What tool is used to install Oetiker clamps?
Use the Oetiker Standard Jaw Pincer Tool .

Do you sell a clamp assortment?
Yes. The Oetiker Clamp Pack with Tool includes common clamp sizes and an installation tool.

Searchable Part Numbers & Terms

8002, Pro Marine 8002, 1/4 primer bulb, 1/4 marine primer bulb, outboard primer bulb, boat fuel primer bulb, marine fuel bulb, outboard fuel bulb, 1/4 fuel line, 1/4 outboard fuel hose, 315-014, MPI 315-014, 1/4 Type B fuel hose, 314-1, MPI 314-1, 1/4 Type A fuel hose, Oetiker 4-133, Oetiker 4-170, marine fuel line clamp, Oetiker fuel line clamp, primer bulb fuel line, marine fuel system, outboard fuel line

How to Order Bulk Fuel Hose

This fuel hose is sold by the foot. Enter the quantity based on the continuous hose length required for your installation.

For example, if your fuel-line run requires 6 feet of hose, order a quantity of 6.

Type B Marine Fuel Hose

Marine fuel hose classifications identify how the hose is intended to be used within a boat's fuel system.

Type B fuel hose is commonly used for exposed or above-deck applications where that hose classification is appropriate. It does not carry the same additional fire-test classification as Type A marine fuel hose.

If your fuel line passes through an enclosed area or the installation specifically requires Type A hose, use the Type A option linked below.

Complete Your 1/4" Fuel Line Setup

Build a complete 1/4" outboard fuel-line setup with the matching clamp, primer bulb and installation tools shown below.

Oetiker 4-133 Ear Clamp - 10 Pack

Matching Oetiker ear clamp for the MPI 315-014 1/4" Type B fuel hose.

Clamp Size: 4-133

View Oetiker 4-133 Clamp

Pro Marine 8002 - 1/4" Primer Bulb

Matching 1/4" primer bulb for building or repairing marine outboard fuel-line assemblies using 1/4" hose.

Hose Size: 1/4"

View 1/4" Primer Bulb

Oetiker Standard Jaw Pincer Tool

Installation tool for properly closing Oetiker ear clamps on marine fuel-line connections.

View Oetiker Pincer Tool

Oetiker Clamp Pack with Tool

Complete assortment of common Oetiker clamp sizes with the installation tool included. A convenient option for technicians and marine shops servicing multiple hose sizes.

View Oetiker Clamp Pack

1/4" Type A Alternative

MPI 1/4" Type A Marine Fuel Hose - 314-1

Use the Type A version when the installation requires the additional Type A fire-resistant marine fuel-hose classification.

Inside Diameter: 1/4"
Fuel Hose Type: Type A
Matching Clamp: Oetiker 4-170

View 1/4" Type A Fuel Hose

1/4" Fuel Hose Comparison

Why Do Two 1/4" Hoses Use Different Clamps?

The 1/4" measurement refers to the hose's inside diameter. It does not determine the outside diameter of the hose.

Type A and Type B hose use different constructions and wall thicknesses, so their outside diameters can be different even when both have a 1/4" inside diameter.

That is why the MPI 315-014 Type B hose uses Oetiker 4-133, while the MPI 314-1 Type A hose uses Oetiker 4-170.

What This Fuel Hose is Used For

MPI 315-014 1/4" Type B fuel hose can be used for building, replacing or repairing marine fuel lines where 1/4" hose and a Type B classification are appropriate.

Because this hose is sold in bulk by the foot, it can be paired with the correct primer bulb, fittings and clamps to create a custom-length fuel-line assembly.

Building a 1/4" Outboard Fuel Line

A typical 1/4" outboard fuel-line assembly may require:

• MPI 315-014 1/4" Type B marine fuel hose
• Pro Marine 8002 1/4" primer bulb
• Correct tank-side fitting or connection
• Correct engine-side fitting or connector
• Oetiker 4-133 ear clamps
• Oetiker pincer installation tool

The exact components required depend on the engine, fuel tank and overall fuel-system layout.

Primer Bulb Selection

Primer bulb fittings should match the inside diameter of the fuel hose. For this 1/4" hose, use the Pro Marine 8002 1/4" Primer Bulb.

View Pro Marine 8002 1/4" Primer Bulb

Key Features & Benefits

• 1/4" inside diameter
• MPI Products marine fuel hose
• Type B marine fuel-hose construction
• Commonly used in exposed and above-deck applications where Type B hose is permitted
• Sold by the foot for custom-length installations
• Matching Oetiker 4-133 clamp available
• Matching Pro Marine 8002 1/4" primer bulb available
• Type A 1/4" alternative available
• Oetiker installation tool available
• Complete Oetiker clamp assortment with tool available

Need Help Choosing the Right Marine Fuel Hose?

Choosing the correct marine fuel line depends on hose diameter, installation location, fuel-hose classification, fittings, primer bulb size and clamp size.

Visit the Pro Marine Fuel Line Technical Center

FAQ

What size is MPI 315-014?
It has a 1/4" inside diameter.

Is this hose sold by the foot?
Yes. Order the quantity corresponding to the total number of feet required.

What type of marine fuel hose is this?
This is MPI Type B marine fuel hose.

Where is Type B fuel hose commonly used?
Type B hose is commonly used for exposed and above-deck fuel-line applications where that classification is permitted.

Which clamp fits MPI 315-014?
Use the Oetiker 4-133 ear clamp .

Which primer bulb fits this 1/4" hose?
Use the Pro Marine 8002 1/4" Primer Bulb .

Can I use the same primer bulb with the 1/4" Type A hose?
Yes. Both the 1/4" Type A and Type B hoses use a 1/4" inside diameter, so the Pro Marine 8002 1/4" primer bulb is the matching hose size.

What if I need Type A 1/4" fuel hose?
Use the MPI 314-1 1/4" Type A fuel hose .

Which clamp fits the 1/4" Type A hose?
The Type A MPI 314-1 hose uses the Oetiker 4-170 ear clamp .

Why do the Type A and Type B 1/4" hoses use different clamps?
The 1/4" measurement is the inside diameter. Different hose construction changes the outside diameter, so the clamp must be matched to the specific hose.

Searchable Part Numbers & Terms

315-014, MPI 315-014, 1/4 fuel hose, 1/4 marine fuel hose, 1/4 boat fuel line, 1/4 outboard fuel hose, Type B marine fuel hose, Type B fuel line, marine fuel line by the foot, bulk marine fuel hose, above deck fuel hose, MPI fuel line, Oetiker 4-133, 4-133 fuel hose clamp, 8002, Pro Marine 8002, 1/4 primer bulb, marine primer bulb, outboard primer bulb, 314-1, 1/4 Type A fuel hose, Oetiker 4-170, marine fuel hose, outboard fuel line, boat fuel hose

How to Order Bulk Fuel Hose

This hose is sold by the foot. Select the quantity based on the total continuous length of hose required for your installation.

For example, if you need approximately 8 feet of fuel hose, order a quantity of 8.

What Does USCG Type B1/B2 Fuel Hose Mean?

Marine fuel hose classifications help identify where and how a hose is designed to be used within a boat's fuel system.

The "B" designation identifies marine fuel hose that does not carry the same USCG fire-test requirement as Type A hose. For that reason, Type B hose is commonly associated with exposed or above-deck fuel-line installations, while Type A hose is the appropriate choice where the installation requires the additional fire-resistant Type A classification.

The numbers "1" and "2" refer to fuel permeation performance. Type 1 is the lower-permeation classification and is the classification normally associated with fuel-feed hose intended to contain fuel continuously. Type 2 permits greater permeation and is used for applications such as certain fill and vent arrangements.

Complete Your 5/16" Fuel Line Setup

The correct hose is only one part of a reliable marine fuel-line installation. Pro Marine stocks the matching clamps, primer bulb and installation tools needed to build or service your fuel line.

Oetiker 4-153 Ear Clamp - 10 Pack

The matching Oetiker ear clamp for this MPI 5/16" Type B fuel hose. Provides a clean, secure connection at fuel fittings and components.

View Oetiker 4-153 Clamp

Pro Marine 8004 - 5/16" Primer Bulb

5/16" primer bulb for building or servicing a marine outboard fuel-line assembly using 5/16" fuel hose.

View 5/16" Primer Bulb

Oetiker Standard Jaw Pincer Tool

Installation tool for properly closing Oetiker ear clamps when assembling marine fuel lines.

View Oetiker Pincer Tool

Pro Marine Oetiker Clamp Pack with Tool

Complete assortment containing common Oetiker clamp sizes plus the installation tool. A convenient option for marine shops, technicians and customers servicing multiple hose sizes.

View Oetiker Clamp Pack

Mercury OEM 5/16" Fuel Hose Available

Mercury OEM 5/16" Silver Fuel Hose

Prefer the Mercury factory fuel hose? Pro Marine also stocks Mercury OEM 5/16" silver fuel hose sold by the foot.

The Mercury hose uses a different outside diameter than this MPI hose and therefore requires a different Oetiker clamp: 4-145.

View Mercury OEM 5/16" Fuel Hose

View Oetiker 4-145 Clamp for Mercury Fuel Hose

Why Doesn't Every 5/16" Fuel Hose Use the Same Clamp?

5/16" identifies the hose's inside diameter, not its outside diameter. Different hose constructions can have different wall thicknesses and therefore different outside diameters.

That is why this MPI 315-056 Type B hose uses Oetiker clamp 4-153, while the Mercury OEM 5/16" silver hose uses Oetiker clamp 4-145.

Always match the clamp to the specific hose being installed rather than selecting a clamp based only on the hose's inside diameter.

What This Fuel Hose is Used For

This 5/16" bulk marine fuel hose can be used when building, repairing or replacing fuel lines in compatible marine applications where USCG Type B hose is appropriate.

Selling the hose by the foot allows boat owners and marine technicians to build the required length and add the appropriate primer bulb, connectors, fittings and clamps for the specific installation.

Building a 5/16" Outboard Fuel Line

A typical 5/16" outboard fuel-line setup may require:

• 5/16" marine fuel hose
• 5/16" primer bulb
• Correct engine-side fuel fitting or connector
• Correct tank-side fitting or connection
• Correctly sized Oetiker ear clamps
• Oetiker pincer tool for clamp installation

The exact components depend on the engine, fuel tank and layout of the boat's fuel system.

Key Features & Benefits

• 5/16" inside diameter marine fuel hose
• USCG Type B1/B2 rated hose
• MPI Products marine fuel line
• Designed for exposed and above-deck applications where Type B hose is permitted
• Sold by the foot for custom-length installations
• Matching Oetiker 4-153 clamp available
• Compatible 5/16" primer bulb available
• Type A 5/16" alternative available for applications requiring Type A hose
• Mercury OEM 5/16" silver fuel hose alternative available

Need Help Choosing the Right Marine Fuel Hose?

Hose diameter is only one part of choosing the correct marine fuel line. The hose classification, installation location, fuel-system design, fittings, primer bulb and clamp size should also be considered.

Visit the Pro Marine Fuel Line Technical Center

FAQ

What size is this fuel hose?
This hose has a 5/16" inside diameter.

Is the hose sold by the foot?
Yes. Order the quantity corresponding to the number of feet needed for your installation.

What does USCG Type B mean?
Type B marine fuel hose meets the applicable SAE marine fuel-hose performance classification but does not carry the same USCG fire-test requirement as Type A hose. It is commonly used in exposed or above-deck applications where Type B hose is permitted.

What is the difference between B1 and B2?
The number identifies the hose's permeation classification. Type 1 has the lower permeation limit and is normally associated with fuel-feed applications intended to contain fuel continuously. Type 2 allows greater permeation and is used for certain other fuel-system applications.

Can I use this hose below deck?
Fuel-hose requirements depend on the installation. For enclosed or below-deck installations requiring the Type A fire-resistant classification, use the 5/16" Type A fuel hose .

Which Oetiker clamp fits this hose?
Use the Oetiker 4-153 ear clamp with this MPI 315-056 hose.

Which primer bulb fits this hose?
The Pro Marine 8004 5/16" Primer Bulb is the matching hose size.

Do you sell a Mercury OEM 5/16" fuel hose?
Yes. Pro Marine stocks Mercury OEM 5/16" silver fuel hose by the foot. The Mercury hose uses Oetiker clamp 4-145 rather than the 4-153 clamp used with this MPI hose.

Why are there different clamps for two 5/16" hoses?
The 5/16" measurement refers to inside diameter. Hose outside diameter can vary depending on wall thickness and construction, so the correct Oetiker clamp must be matched to the specific hose.

Searchable Terms

315-056, MPI 315-056, 5/16 fuel hose, 5/16 marine fuel hose, 5/16 boat fuel line, 5/16 outboard fuel hose, USCG Type B fuel hose, Type B1 fuel hose, Type B2 fuel hose, marine fuel line by the foot, bulk marine fuel hose, above deck fuel hose, outboard fuel line, boat fuel hose, Oetiker 4-153, 4-153 fuel hose clamp, 5/16 primer bulb, marine primer bulb, Mercury 5/16 fuel hose, Type A marine fuel hose, Type B marine fuel hose

What is Type A1 Marine Fuel Hose?

Type A1 marine fuel hose is designed for fuel-feed applications requiring a marine hose with enhanced fire-resistant performance.

Type A1 hose is commonly used in permanent marine fuel systems and installations where the fuel line passes through enclosed or below-deck areas.

When selecting fuel hose, both the inside diameter and the required hose classification should be verified for the installation.

Why Use 1/2" Fuel Hose?

A 1/2" fuel line provides greater internal flow area than the more common 1/4", 5/16" and 3/8" marine fuel hoses.

It may be used in applications where the engine or fuel-system design requires a larger fuel supply line to support higher fuel-flow demand.

Always follow the engine or boat manufacturer's required hose diameter rather than increasing or decreasing hose size without verifying the fuel-system requirements.

Matching Fuel Hose Clamp

German-Style Hose Clamp - 4-4

Recommended hose clamp for the MPI 360-12 1/2" Type A1 marine fuel hose.

German-style hose clamps provide a secure connection for larger marine fuel-hose applications.

View German-Style Hose Clamp

Fuel Line Tools and Clamp Assortment

Oetiker Standard Jaw Pincer Tool

Useful installation tool for Oetiker ear clamps used throughout many marine fuel-line systems.

While this 1/2" hose uses the German-style clamp shown above, the pincer tool is useful when servicing other fuel-hose sizes that use Oetiker ear clamps.

View Oetiker Pincer Tool

Oetiker Clamp Pack with Tool

Complete assortment of common Oetiker clamp sizes with the installation tool included.

A convenient option for marine shops and technicians servicing different fuel-hose sizes throughout a boat or engine.

View Oetiker Clamp Pack

What This Fuel Hose is Used For

MPI 360-12 is used when building, repairing or replacing a marine fuel supply line requiring 1/2" Type A1 hose.

Typical applications involve larger marine fuel systems where increased fuel-flow capacity is required and the installation calls for Type A1 hose.

Typical 1/2" Fuel-Line Setup

Depending on the boat and engine, a 1/2" marine fuel-line installation may include:

• MPI 360-12 1/2" Type A1 marine fuel hose
• German-style 4-4 hose clamps
• Fuel tank pickup or shutoff valve
• Fuel/water separator or filter assembly
• Engine fuel-system connection
• Application-specific fittings and adapters

Primer Bulb vs. Larger Fuel Systems

Smaller outboard fuel systems commonly use 1/4", 5/16" or 3/8" hose with an inline primer bulb.

A 1/2" fuel supply line generally indicates a higher-flow fuel system, and a hand primer bulb is not normally part of that configuration.

The engine manufacturer's fuel-system requirements should always take priority when determining hose size, fittings, filters and priming components.

Fuel Hose Size Comparison

Key Features & Benefits

• 1/2" inside diameter
• MPI Products marine fuel hose
• Type A1 marine fuel-hose classification
• Designed for fuel-feed applications requiring Type A1 hose
• Suitable for higher-flow marine fuel systems
• Common choice for enclosed or below-deck fuel-line routing when 1/2" hose is required
• Matching German-style 4-4 hose clamp available
• Primer bulb normally not used with 1/2" fuel-line systems
• Fuel-system installation tools and clamp assortment available

Need Help Choosing the Right Marine Fuel Hose?

Fuel-line diameter, Type A or Type B classification, fuel-system flow requirements, fittings, filters and clamp selection all need to match the boat and engine installation.

Visit the Pro Marine Fuel Line Technical Center

FAQ

What size is MPI 360-12?
This fuel hose has a 1/2" inside diameter.

What type of fuel hose is 360-12?
It is Type A1 marine fuel hose.

What is Type A1 fuel hose used for?
Type A1 is used for marine fuel-feed applications requiring the additional fire-resistant performance associated with Type A hose.

Can this hose be used below deck?
Type A1 hose is commonly used in enclosed and below-deck fuel-system installations when the fuel system calls for this hose size and classification.

Which clamp fits this 1/2" hose?
Use the German-Style 4-4 Hose Clamp .

Does this hose use an Oetiker ear clamp?
The recommended clamp for this hose is the German-style 4-4 hose clamp.

Does 1/2" fuel hose use a primer bulb?
A primer bulb is not normally used in a fuel system requiring 1/2" hose. Larger lines are typically used in higher-flow fuel systems with a different priming and fuel-delivery arrangement.

Should I use 1/2" hose just to increase fuel flow?
Use the hose diameter specified for the engine and fuel system. Increasing hose size without verifying the complete system is not a substitute for following the manufacturer's fuel-system requirements.

Do you sell fuel-line clamp tools?
Yes. Pro Marine stocks the Oetiker Standard Jaw Pincer Tool for fuel-line applications using Oetiker ear clamps.

Do you sell a complete clamp assortment?
Yes. The Oetiker Clamp Pack with Tool includes commonly used clamp sizes and an installation tool.

Searchable Part Numbers & Terms

360-12, MPI 360-12, 1/2 fuel hose, 1/2 marine fuel hose, 1/2 boat fuel line, 1/2 Type A1 fuel hose, Type A1 marine fuel line, marine fuel supply hose, high flow marine fuel hose, large outboard fuel line, boat fuel hose, below deck fuel hose, enclosed marine fuel line, marine fuel line, German style hose clamp, 4-4 hose clamp, marine fuel hose clamp, bulk marine fuel hose, marine fuel system, fuel hose by the foot

What This Fuel Fill Hose is Used For

FILLHOSE-112 is intended for the fuel-fill portion of a permanently installed marine fuel system.

In a typical installation, the hose runs from the fitting directly behind the deck-mounted fuel cap down to the fuel tank's fill-neck connection.

Common applications include:

• Boat fuel tank fill hose
• Deck fill to fuel tank connection
• Replacement of aged or deteriorated marine fuel fill hose
• Boat restoration and fuel-system rerigging
• New permanent marine fuel tank installations

What Does USCG Type A2 Mean?

Type A2 is a marine fuel-hose classification used for compatible fuel-system applications including fuel fill and vent lines.

Under federal marine fuel-system requirements, Type A hose is constructed to meet a fire-resistance test. Type A2 is a Class 2 hose designation.

The important application distinction for this product is that Type A2 hose is suitable for a marine fuel fill or vent line. It should not be confused with the smaller Type A1 fuel hose commonly used in fuel-feed applications.

Matching 1-1/2" Fuel Fill Hose Clamp

German-Style Hose Clamp - 4-8

Matching clamp for the 1-1/2" fuel fill hose installation.

Pro Marine's 4-8 German-style clamp has a 27-51mm / 1.05-1.99" clamping range and is made from 316 stainless steel.

Secure the hose at the deck-fill fitting and fuel-tank fill neck according to the requirements of the installation.

View 4-8 German-Style Hose Clamp

1-1/2" Chrome Gas Deck Fill

Chrome 1-1/2" Gas Deck Fill - 3-5740

Universal 1-1/2" chrome gas deck fill for compatible marine fuel systems.

The fuel fill hose connects to the hose barb beneath the deck fill and routes gasoline down to the permanent fuel tank.

View 1-1/2" Chrome Gas Deck Fill

1-1/2" and 2" Fuel Fill Hose Options

Need 2" Fuel Fill Hose?

2" Type A2 Fuel Fill Hose - FILLHOSE-2

Larger Type A2 fuel fill hose for marine installations using a 2" tank fill and deck-fill connection.

View 2" Fuel Fill Hose

German-Style Hose Clamp - 4-9

Matching clamp option supplied for Pro Marine's 2" Type A2 fuel fill hose.

View 4-9 Hose Clamp

Fuel Fill Hose Installation Tips

• Match the hose inside diameter to the deck fill and fuel-tank fill connection.
• Use marine fuel hose specifically designed for fuel-fill applications.
• Use properly sized corrosion-resistant hose clamps.
• Make sure the hose is fully seated on each fitting before clamping.
• Avoid sharp bends that can restrict fuel flow while filling the tank.
• Route the hose so it cannot be crushed by batteries, storage or other equipment.
• Keep the hose away from sharp edges and moving components.
• Inspect the entire fill hose for cracking, hardening and deterioration.
• Check all connections for fuel seepage after installation.

When Should Marine Fuel Fill Hose Be Replaced?

Fuel fill hose should be inspected whenever the fuel tank, deck fill or surrounding rigging is serviced.

Consider replacement if you find:

• Cracking in the outer hose
• Dry, hardened or brittle hose
• Soft or swollen areas
• Abrasion or chafing
• Fuel odor around the fill-hose area
• Visible fuel seepage
• Damaged or heavily corroded clamps
• Hose that no longer fits securely on the fill fitting or tank

How the Marine Fuel Fill System Works

When gasoline is added through the deck-mounted gas cap, it travels through the large-diameter fuel fill hose and into the permanent fuel tank.

A separate fuel-tank vent system allows displaced air to escape while the tank is being filled.

The fuel fill hose, deck fill, tank connection and vent system all need to remain correctly routed and unobstructed for reliable refueling.

Key Features and Benefits

• 1-1/2" marine fuel fill hose
• USCG Type A2 hose
• Designed for deck-fill to fuel-tank applications
• Large diameter for marine fuel filling
• Matching 4-8 German-style clamp available
• Matching 1-1/2" chrome deck fill available
• 2" Type A2 fuel fill hose also available
• Useful for new fuel-system installations and replacement projects

FAQ

What size is FILLHOSE-112?
FILLHOSE-112 is 1-1/2" inside-diameter marine fuel fill hose.

What is this hose used for?
It connects the boat's deck-mounted fuel fill to the fill connection on the permanent marine fuel tank.

Is FILLHOSE-112 Type A2?
Yes. This hose is listed as USCG Type A2.

Can I use this as the fuel hose from the tank to the engine?
This product is intended as large-diameter fuel fill hose. Use the proper marine fuel-supply hose specified for the tank-to-engine portion of the fuel system.

Which clamp fits the 1-1/2" fuel fill hose?
Pro Marine pairs it with the 4-8 German-Style Hose Clamp .

Do you stock a 1-1/2" fuel deck fill?
Yes. Pro Marine stocks the 3-5740 Chrome 1-1/2" Gas Deck Fill .

Do you have 2" fuel fill hose?
Yes. Pro Marine also stocks FILLHOSE-2 2" Type A2 Fuel Fill Hose .

How do I know whether I need 1-1/2" or 2" hose?
Measure or verify the hose connection size on both the deck fill and the fuel tank. The replacement hose needs to match the fittings used in the boat's fuel-fill system.

Searchable Terms

FILLHOSE-112, 1-1/2 fuel fill hose, 1.5 inch fuel fill hose, Type A2 fuel hose, USCG Type A2 hose, marine fuel fill hose, boat gas fill hose, fuel tank fill hose, deck fill hose, gas tank filler hose, 4-8 hose clamp, 3-5740, FILLHOSE-2, marine fuel tank hose

What This Fuel Fill Hose is Used For

FILLHOSE-2 is intended for the fuel-fill section of a permanently installed marine fuel system.

In a typical installation, the hose connects the fitting underneath the deck-mounted gas fill to the fill neck on the fuel tank.

Common applications include:

• Boat fuel tank fill hose
• Deck fill to fuel tank plumbing
• Replacement of old or deteriorated fuel fill hose
• Boat restoration and fuel-system rerigging
• New permanent marine fuel-tank installations

What Does Type A2 Fuel Hose Mean?

Type A2 is a marine fuel-hose classification commonly used for fuel fill and vent applications.

The Type A designation indicates a hose intended for marine fuel systems where fire resistance is required. The A2 classification is used for specific fill and vent applications rather than the smaller engine fuel-feed line.

For this product, the important point is that it is designed as a large-diameter marine fuel fill hose.

Matching 2" Fuel Fill Hose Clamp

German-Style Hose Clamp - 4-9

Matching clamp for Pro Marine's 2" Type A2 fuel fill hose.

Use properly sized corrosion-resistant clamps to secure the fuel fill hose at the deck-fill fitting and fuel-tank connection.

View 4-9 German-Style Hose Clamp

1-1/2" and 2" Fuel Fill Hose Options

Need 1-1/2" Fuel Fill Hose Instead?

1-1/2" Type A2 Fuel Fill Hose - FILLHOSE-112

Smaller Type A2 marine fuel fill hose for installations using 1-1/2" deck-fill and fuel-tank connections.

View 1-1/2" Fuel Fill Hose

German-Style Hose Clamp - 4-8

Matching clamp for the 1-1/2" Type A2 fuel fill hose.

View 4-8 Hose Clamp

1-1/2" Chrome Gas Deck Fill

1-1/2" Chrome Gas Deck Fill - 3-5740

Pro Marine also stocks a 1-1/2" chrome deck fill for compatible marine fuel systems using 1-1/2" fill hose.

This deck fill is not the matching 2" connection for FILLHOSE-2, but it is available for installations using the smaller 1-1/2" hose system.

View 1-1/2" Chrome Gas Deck Fill

How a Marine Fuel Fill System Works

The fuel-fill system provides the path from the deck-mounted fuel cap to the boat's permanent fuel tank.

During refueling:

1. Fuel enters through the deck fill.
2. The fuel travels through the large-diameter fill hose.
3. The hose delivers the fuel to the tank's fill connection.
4. The tank's separate vent system allows displaced air to escape.

The deck fill, fuel fill hose, tank connection and vent system all need to be correctly sized and routed for reliable filling.

Fuel Fill Hose Installation Tips

• Verify the deck-fill and tank-fill connection size before ordering hose.
• Use hose specifically rated for marine fuel-fill service.
• Make sure the hose fully seats over each hose barb or fitting.
• Use properly sized corrosion-resistant clamps.
• Avoid tight bends and kinks that can restrict fuel flow.
• Plan the routing before cutting the hose.
• Keep the hose away from sharp edges and moving parts.
• Do not allow batteries or stored equipment to crush the hose.
• Check both ends for leaks or seepage after installation.

Why Fuel Fill Hose is So Heavy Duty

Fuel fill hose is much larger and more heavily constructed than the smaller fuel hose used to feed an engine.

It has to handle:

• Large volumes of fuel during refueling
• Marine vibration and movement
• Fuel exposure
• Heat and environmental exposure
• The bends required between the deck fill and fuel tank

Because of its construction, fuel fill hose can be relatively stiff. Planning the routing before installation is especially important.

When Should Fuel Fill Hose Be Replaced?

Inspect the fill hose whenever the deck fill, fuel tank or surrounding rigging is serviced.

Replace the hose if you find:

• Cracks in the outer surface
• Hard, dry or brittle rubber
• Soft or swollen areas
• Abrasion or chafe damage
• Fuel seepage
• Persistent gasoline odor near the hose
• Loose, damaged or corroded clamps
• A hose that no longer fits tightly on the fittings

Key Features and Benefits

• 2" marine fuel fill hose
• Type A2 construction
• Designed for deck-fill to fuel-tank plumbing
• Large-diameter marine fuel-system application
• Matching 4-9 German-style clamp available
• 1-1/2" Type A2 fuel fill hose also available
• Suitable for replacement and new fuel-system installations
• Helps provide a dedicated path from the deck fill to the fuel tank

FAQ

What size is FILLHOSE-2?
FILLHOSE-2 is 2" inside-diameter marine fuel fill hose.

What is FILLHOSE-2 used for?
It is used to connect a compatible deck-mounted fuel fill to the fill connection on a permanent marine fuel tank.

Is this a Type A2 hose?
Yes. FILLHOSE-2 is a Type A2 marine fuel fill hose.

Can I use this as the fuel-supply line to the engine?
This product is intended as large-diameter fuel fill hose. Use the correct marine fuel-supply hose for the tank-to-engine fuel line.

Which clamp fits this hose?
Pro Marine pairs FILLHOSE-2 with the 4-9 German-Style Hose Clamp .

Do you have a smaller fuel fill hose?
Yes. Pro Marine also stocks FILLHOSE-112 1-1/2" Type A2 Fuel Fill Hose .

How do I know whether I need 1-1/2" or 2" hose?
Verify the hose-barb diameter on both the deck fill and the fuel tank. The hose size needs to match the fittings used in the boat.

Why is fuel fill hose so stiff?
Marine fuel fill hose is heavily constructed for its application, which makes it less flexible than smaller engine fuel hose. Plan bends and hose routing before installation.

Searchable Terms

FILLHOSE-2, 2 inch fuel fill hose, Type A2 fuel hose, marine fuel fill hose, boat gas fill hose, deck fill hose, fuel tank fill hose, marine gas tank hose, rigid fuel fill hose, 4-9 hose clamp, FILLHOSE-112, 1-1/2 fuel fill hose, boat fuel hose, marine fuel tank plumbing