Ultraflex S40 Splashwell Steering Cable Plate Mounting Kit

The Ultraflex S40 / 31917G Splashwell Steering Cable Mounting Kit is a complete articulated bulkhead support for compatible mechanical steering cables. It allows the steering cable to pass through the boat's splashwell or side bulkhead while maintaining a secure mounting point between the cable and outboard engine.

The S40 uses a corrosion-resistant splashwell mounting flange and an aluminium support tube. The supplied product data specify a 280mm tube length and 28mm tube diameter. The mounting assembly has a 90mm counterflange diameter, 78mm flange diameter and 44mm centre opening.

Product Identification

• Brand: Ultraflex
• Model: S40
• Manufacturer part number: 31917G
• Product category: Mechanical steering cable support
• Product type: Splashwell or bulkhead steering cable mount
• Supply type: Complete mounting assembly
• Primary function: Supports a steering cable where it passes through a splashwell bulkhead
• Mounting design: Articulated flange
• Support tube material: Aluminium
• Mounting flange: Corrosion-resistant construction
• Support tube length: 280mm
• Support tube diameter: 28mm
• Counterflange outside diameter: 90mm
• Flange outside diameter: 78mm
• Centre bulkhead opening: 44mm
• Opposed fixing-hole centres: 64mm
• Fixing holes: 4 x 6.5mm
• Steering type: Mechanical cable steering
• Typical application: Outboard splashwell installation
• Closest Multiflex functional equivalent: Multiflex S1
• Stainless-tube alternative: Ultraflex S40SS
• Replacement tube: Ultraflex S40T
• Steering cable included: No
• Engine link arm included: No

What Is the Ultraflex S40 Used For?

The S40 supports the stationary outer section of a compatible mechanical steering cable where the cable passes through the boat's splashwell or side bulkhead.

Securing the outer cable allows the moving cable output to transfer push-pull movement to the outboard engine through a separately selected steering link arm.

The S40 can form part of a correctly specified:

• Outboard mechanical steering installation
• Splashwell-mounted steering system
• Bulkhead steering cable pass-through
• New installation where a separate cable support is required
• Replacement of an existing articulated splashwell support
• Installation where the cable cannot be mounted directly through a suitable engine tilt tube
• Mechanical steering system requiring limited angular alignment at the bulkhead

The S40 is an engine-end cable support rather than a general-purpose intermediate cable clip. It does not replace the steering helm, steering cable or engine connection arm.

What Is Included?

• 1 x aluminium support tube
• 1 x ring nut
• 1 x articulated ball
• 2 x mounting flanges
• 1 x rear counterflange
• 4 x M6 x 40mm mounting screws
• 4 x elastic washers
• 4 x M6 nuts

Not included unless expressly stated:

• Mechanical steering cable
• Steering helm
• Steering wheel
• Dashboard bezel
• Engine steering link arm
• Engine tiller arm
• Engine-specific adaptor
• Transom clamp block
• Hydraulic steering cylinder
• Hydraulic hoses
• Other installation-specific steering hardware

What Are the S40 Dimensions?

• Support tube length: 280mm
• Support tube diameter: 28mm
• Counterflange outside diameter: 90mm / 3.54in
• Flange outside diameter: 78mm / 3.07in
• Opposed fixing-hole centres: 64mm / 2.52in
• Centre bulkhead opening: 44mm / 1.73in
• Number of fixing holes: 4
• Fixing-hole diameter: 6.5mm / 0.25in

The 90mm measurement refers to the outside diameter of the rear counterflange, rather than the support tube or front mounting flange.

The available Ultraflex product data do not state the tube thread size, flange thickness, maximum bulkhead thickness, maximum articulation angle, product weight, maximum steering load or maximum engine horsepower.

What Does the Articulated Ball Mount Do?

The S40 includes a ball positioned between the two mounting flanges.

This articulated arrangement allows the support tube to align with the steering cable and engine connection instead of forcing the cable to pass through the bulkhead at a fixed angle.

The ball-and-flange assembly helps provide:

• Controlled angular alignment
• Reduced side loading on the steering cable
• A secure bulkhead support point
• Alignment between the cable and engine tiller arm
• Limited movement as the steering system operates

The ball material and maximum permitted articulation angle are not stated in the available product data.

Which Steering Cables Are Compatible?

The Ultraflex S40 installation manual does not publish a definitive list of compatible steering cable models.

The selected mechanical steering cable must have a retaining nut and output arrangement that can:

• Pass through the S40 support tube
• Thread securely onto the support tube
• Seat firmly against the tube
• Move through its complete steering travel
• Connect to the engine through a suitable link arm
• Operate without exceeding its minimum bend radius

Before ordering, confirm:

• Steering cable manufacturer
• Steering cable model
• Cable retaining-nut thread
• Cable output-end design
• Cable travel
• Cable length
• Minimum bend radius
• Engine-side connection
• Required steering link arm
• Complete steering-system rating

Is the S40 the Ultraflex Equivalent of the Multiflex S1?

The Ultraflex S40 is the closest functional equivalent to the Multiflex S1 Splashwell Mounting Kit.

Both products are designed to:

• Support a mechanical steering cable at the splashwell
• Pass the steering cable through a side bulkhead
• Provide an articulated mounting point
• Use an aluminium support tube
• Connect the cable output to the engine through a separate link arm

The S40 should still be treated as a functional equivalent rather than an automatically interchangeable replacement.

Before replacing a Multiflex S1 with an Ultraflex S40, compare the tube dimensions, flange diameter, mounting-hole spacing, centre opening, cable retaining-nut thread, bulkhead thickness and engine link-arm geometry.

How Does the S40 Differ From the S40SS and S40T?

Ultraflex S40 / 31917G

• Complete splashwell mounting assembly
• Corrosion-resistant articulated flange
• Aluminium support tube
• Includes flanges, ball, counterflange and mounting hardware

Ultraflex S40SS / 41552Z

• Complete splashwell mounting assembly
• Same general mounting application
• Stainless-steel support tube

Ultraflex S40T

• Replacement tube only
• Does not include the ball, flanges, counterflange or complete mounting hardware

Does the S40 Replace an Engine Tilt Tube?

The S40 provides an alternative cable-support arrangement where the steering cable must pass through a splashwell or bulkhead instead of being supported through a suitable engine tilt tube.

It should not be treated as a universal replacement for every tilt-tube installation. Correct use depends on the splashwell structure, steering cable interface, cable travel, engine tiller position, link arm and available steering and tilt clearance.

Does the S40 Include a Steering Link Arm?

No. The engine steering link arm is not included.

The required link arm must be selected according to:

• Outboard engine manufacturer
• Engine model
• Engine production year
• Steering cable output end
• Engine tiller mounting point
• Required arm length
• Mounting-hole diameter
• Steering travel
• Engine tilt clearance

Can the S40 Be Used with Hydraulic Steering?

No. The S40 is a mechanical steering cable support.

It is not a hydraulic steering cylinder bracket, hydraulic hose bulkhead fitting, hydraulic helm component, hydraulic tie bar or hydraulic engine mounting plate.

How Is the S40 Installed?

1. Screw the articulated ball onto the longer threaded section of the support tube.
2. Position the two flanges over the ball.
3. Screw the ring nut onto the shorter threaded section of the tube.
4. Insert the steering cable into the preassembled support tube.
5. Tighten the steering cable retaining nut against the support tube.
6. Place the steering cable at half stroke.
7. Connect the moving cable end to the engine tiller arm.
8. Use this position to locate the mounting flanges on the boat bulkhead.
9. Drill the bulkhead using the S40 drilling template.
10. Position the counterflange behind the bulkhead.
11. Install the four M6 x 40mm screws.
12. Secure the assembly with the elastic washers and M6 nuts.
13. Check the complete steering and engine tilt movement before use.

Construction and Design

• Ultraflex S40 splashwell steering cable mount
• Manufacturer part number 31917G
• Complete articulated mounting assembly
• Designed for mechanical steering cables
• Suitable for splashwell or side-bulkhead installation
• Corrosion-resistant mounting flange
• Aluminium support tube
• 280mm support-tube length
• 28mm support-tube diameter
• Articulated ball mounting
• Two front flanges
• One rear counterflange
• One retaining ring nut
• Four M6 x 40mm mounting screws
• Four elastic washers
• Four M6 nuts
• 90mm counterflange diameter
• 78mm flange diameter
• 64mm opposed fixing-hole centres
• 44mm centre opening
• Four 6.5mm fixing holes
• Steering cable supplied separately
• Engine link arm supplied separately
• No hydraulic components
• No electrical components

Installation and Safety

• Confirm that the installation requires a splashwell or bulkhead steering cable mount
• Verify the exact S40 / 31917G model
• Confirm compatibility with the selected mechanical steering cable
• Check the cable retaining-nut thread against the S40 tube
• Verify the required cable length and travel
• Position the steering cable at half stroke before locating the flanges
• Connect the cable end to the engine tiller before drilling
• Use the official S40 drilling template
• Check that the bulkhead is structurally suitable
• Check the 90mm counterflange clearance behind the bulkhead
• Drill the 44mm centre opening accurately
• Drill four 6.5mm fixing holes on the specified 64mm centres
• Assemble the ball, flanges and ring nut in the correct order
• Ensure the cable retaining nut seats fully against the tube
• Install the counterflange behind the bulkhead
• Tighten the M6 fasteners evenly
• Do not distort the flanges or mounting surface
• Maintain the steering cable's minimum bend radius
• Avoid forcing the cable sideways
• Turn the steering fully from port to starboard
• Check that the engine reaches both steering positions without binding
• Repeat the steering check throughout the engine's tilt range
• Ensure the cable, support tube and link arm do not contact the splashwell
• Recheck the fasteners after the initial steering test
• Inspect the assembly regularly for corrosion, cracking or looseness
• Do not operate the boat if the steering cable or S40 assembly binds

Marine steering is safety-critical. Installation should be completed according to the current Ultraflex, steering-cable and engine instructions by a competent marine technician.

Key Features

• Ultraflex S40 splashwell steering cable mounting kit
• Model S40
• Manufacturer part number 31917G
• Complete articulated bulkhead support
• Allows a mechanical steering cable to pass through the splashwell
• Corrosion-resistant splashwell mounting flange
• Aluminium support tube
• 280mm support-tube length
• 28mm support-tube diameter
• 90mm counterflange outside diameter
• 78mm flange outside diameter
• 44mm centre bulkhead opening
• 64mm opposed fixing-hole centres
• Four 6.5mm fixing holes
• Articulated ball supports cable alignment
• Two mounting flanges included
• Rear counterflange included
• Ring nut included
• Four M6 x 40mm screws included
• Four elastic washers included
• Four M6 nuts included
• Closest Ultraflex functional equivalent to the Multiflex S1
• S40SS available with a stainless-steel tube
• S40T is a replacement tube only
• Steering cable supplied separately
• Engine link arm supplied separately
• Not intended for hydraulic steering
• Cable fit and installation geometry must be confirmed before drilling