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Maximum Security

Maximum SecurityPassenger and Road User safety is of paramount importance to AL-KO Kober and through product design and development, the company has released a range of products and accessories to meet the needs of their customers.

Engineers have studied the relationship between the component parts to understand how they work together, enabling them to design products to maximise safe operation on the road. Continuity of design ensures each component performs correctly and safely in its environment.

AL-KO’s forward thinking innovations are tested in accordance with Government legislation and conform to EC Regulation 94/20.

To ensure safe travel and coupling, the use of the AL-KO AKS3004 Stabiliser and Tow Ball significantly improves the connection between towing vehicle and trailer. The stabiliser grips the tow ball via the four friction pads inside the coupling mechanism. The friction pads generate a stabilising force, reducing snaking and pitching of the trailer.

Stabilisers and Coupling Devices

The use of a stabiliser is becoming the favoured method of coupling, gradually replacing the standard coupling head design as the main form of hitching. To engage the standard coupling head (Fig.1 above), it is positioned over the tow ball and lowered until the handle locks it in position. A safety indicator (Fig.2) tells the user that the head is correctly located onto the tow ball and a wear indicator (Fig.3) shows whether the tow ball or coupling mechanism has worn and needs replacing.

Maximum Security

Stabilisers reduce pitching and snaking of a trailer more effectively than standard coupling devices. The use of the AL-KO AKS3004 Stabiliser provides improved towing stability, ride comfort and optimum road safety and allows the car and trailer to be stabilised quickly in an emergency situation such as sudden heavy winds or overtaking HGV’s.

The AKS3004 Stabiliser can be fitted to most overrun assemblies up to 3000kg. The safety indicator signals that the stabiliser has located correctly onto the tow ball, once the coupling handle has been set. The stabiliser lever can then be lowered, constricting the four friction pads around the tow ball and securely gripping it, to reduce movement. A wear indicator at the base of the coupling handle determines the condition of the front and rear friction pads, whilst wear control for the side pads can be monitored via two arrowhead indicators on the stabiliser lever.

Maximum Security

The stabiliser must be used in conjunction with a 50mm diameter tow ball as per EC directive 94/20 (DIN 47058) to ensure proper coupling between the two vehicles.

The AL-KO AKS3004 Stabiliser provides improved towing stability, ride comfort and most importantly optimum safety on the road.

Stabilisers and Coupling Devices

When using the AL-KO AKS3004 Stabiliser, it is important to fit a tow ball (Fig.7) with sufficient clearance of at least 60mm between the centre of the ball and the base of the neck and 68mm from the centre of the tow ball to the nearest obstruction on the towing vehicle e.g. bumper, to ensure correct operation. This will allow the stabiliser to perform a 25° axial rotation movement (Fig.8).

Maximum Security

There are many tow balls on the market that do not have enough clearance and should not be used with the AKS3004 Stabiliser. The risk of vehicles becoming un-hitched, damage to the stabiliser occurring, or a very serious accident happening, is much greater if an incorrect type of tow ball is fitted.

A number of designs of tow balls are available in the market including, swan neck, bolt-in and the flange type (two bolt fixing). The swan neck, including both fixed and detachable versions, can accommodate the use of the stabiliser, as they have a long, tapered neck giving plenty of clearance. Bolt-in styles are permissible only if the fixing thread is locked or welded to prevent turning. The AL-KO flange type tow ball also conforms (Witter part no. Z13).

Maximum Security

To ensure correct function, the tow ball should have any paint or protective coating removed right back to the bare metal. Any paint or coating left on the ball can, under friction, form tiny ball-bearing like deposits that score or pit the ball, creating excessive wear, resulting in a reduction of performance from the stabiliser. In all instances it is imperative that the tow ball height is correct in accordance to EC regulations. Measurements taken on a level surface from the ground to either the centre of the tow ball or the centre of the coupling head should not exceed heights indicated below.

Caravans should not exceed: 430mm +/-35mm
Cars should not exceed: 385mm +/-35mm

Monitoring Wear

To maximise performance of both tow ball and stabiliser, it is essential to monitor wear of both products and to carry out periodical maintenance.

To assess the amount of wear in the friction pads, couple the AKS3004 onto the tow ball, without activating the stabiliser. When correctly coupled, the safety indicator button on the head will be in a raised position. At the front of the coupling handle, the wear indicator (Fig. 10) will show if there is any wear in the front and rear pads. If the green section is visible when coupled, the pads are OK. If the red section is visible, then the following conditions may apply:

  • The stabiliser is okay, but the towball has reached its lower limit of 49mm.
  • The stabiliser is worn.
  • The tow ball is the correct diameter, but the front and rear friction pads are worn.
  • A new tow ball can be utilised to ascertain which condition exists.

Wear of the side friction pads needs to be checked independently by removing the red handle on the stabiliser and then applying each arm separately. Both arms have an arrowhead, which needs to line up at the start of the corresponding rectangular groove on the red cover (‘Soft-dock’). When an arm is activated, the friction pads within the head will grip the tow ball. Check the position of the arrowhead in relation to the rectangular groove (Fig.12). If the arrowhead has reached the bottom line of the rectangular groove, the pads are worn and need replacing. Anywhere between these two points, the pads are OK.

Maximum Security

Maintenance and Cleaning

Regular maintenance will improve the service life of both the tow ball and stabiliser. It is recommended to clean the tow ball with thinners, white spirit or brake cleaner to remove grease or other residue. The surface of the tow ball must be free of grooves, rust or seizing marks. If the tow ball is coated with paint or similar, this must be completely removed using 100 or 120 grain emery paper, otherwise excessive wear to the friction pads could cause damage to the stabiliser. If the friction pads in the stabiliser are heavily contaminated, they should be replaced and not cleaned. At no point should grease be used near the friction pads, as this will seriously reduce the effectiveness of the stabiliser. Before each journey, lightly rub the tow ball with fine grade emery paper and the friction pads to keep rust deposits or contaminates to a minimum and optimise performance of the stabiliser.

It is essential to monitor wear and to carry out periodical maintenance.

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