Mechanical Installation Manual (750, 750 Quad)

5.3 Beam-Wise Location

There are several hull features that should be considered when determining the location of the Controllers in a beam-wise orientation.  

As a general rule, the OUTSIDE MOST Controllers must be mounted as far outboard as possible, up to the chines (if the hull has chines). Details on the precise beam wise location is in the following sections.  

Inboard Controllers should be mounted according to different priorities and should follow section 5.4. 

ATTENTION: Mounting the OUTSIDE MOST Controllers towards the centerline of the boat reduces the leverage the system has on the boat and severely reduces roll performance. 

Figure 20 – High Leverage – Left, Low Leverage – Right 
Figure 21 – Incorrect Installation Between Trim Tabs

Chines 

Note: In this instruction manual the term ‘Chine’ is regarding the intersection of the hull bottom and hull side with an abrupt change in deadrise angle. This is sometimes referred to as ‘Reverse Chine’.

Based on the considerations of engine spacing and transom appendages, some installations will require the Controllers to extend outboard of the inboard edge of the chine. An overlap of the outboard chine of 1.5 in. (38 mm) is acceptable. For overlaps greater than 1.5 in. (38 mm), performance may degrade rapidly. The figure below illustrates placement of the outboard edge of the Controller with the following color code: 

  • Green (Outboard of chine up to 1.5 in. (38 mm)) – Ideal
  • Yellow (Inboard of chine up to 1.5 in. (38 mm)) – Good
  • Orange (More than 1.5 in. (38 mm) from chine) – Acceptable*
  • Red (Overhanging Hull Side) – Unacceptable

*Controllers must NOT be mounted far enough inboard to reduce leverage, as outlined above.

Figure 22 – Chine Overlap 

Hull Side Spacing 

It is possible to have an installation where the Controller is mounted too far outboard causing water flowing around the hull side to interfere with the Controller and substantially reduce performance. 

To avoid this issue, the Controller should be mounted at least 1.5 in. (38 mm) inboard of the hull side, as shown below. 

Figure 23 – Hull Side Clearance 

Propeller Tunnels

In the event a hull has propeller tunnels and there is not enough beam to install a Dual Controller system outboard of the tunnel, it is possible to utilize a Quad Controller system.

The outboard controllers should be mounted outboard of the propeller tunnel.

The inboard controllers could be mounted in 2 locations. The inboard controller can be mounted on top of the propeller tunnel if there is a straight section of the tunnel to match with the controller seal plate. Alternatively the inboard controller can be mounted on the deadrise inboard of the propeller tunnel.

Review of other hull features like convex and concave hull bottoms and variable deadrise should be considered with this placement.