MG Tech – MGF LoLarm Installation

Head gasket failure is the nightmare that all MGF and MGTF owners face every time they drive their cars, such are the litany of horror stories about this happening to these models.

One way to detect if this may be about to happen and prevent serious damage is by fitting a system that warns the driver if the coolant level has fallen to a dangerous level.

One such system is the LoLarm II which can be bought online ( and installed by even the most amateur mechanic in less than two hours (or by experienced mechanics such as those at South Coast MG Rover in an hour) – it comes with full instructions and a simple wiring diagram.

The system comes with a copper float, a sensor, wiring to a fuse and earth, a warning buzzer and a green light.

To install start by removing the engine bay cover to access the coolant fluid bottle then remove the bottle itself (two 8mm bolts) being careful to empty any fluid into a container so that the anti-freeze can be re-used if necessary.

Next fit the copper float (which has a magnet) into the bottle and sticking  the sensor to the outside base of the bottle ensuring that it is located directly underneath the float – the system works by setting off an audible alarm if the magnet in the float moves close to the sensor indicating the fluid level has dropped significantly.

As an added precaution use a cable tie around the sensor and bottle to ensure it doesn’t become detached. The cable can also be used to run the wiring through to keep it neat and tidy.

The wiring has two ends, one which needs attaching to a good earthing point, the other has to be run under the engine bay and hood cover, down the vertical carpet behind the seats, under the floor carpets and then to the fuse box below the dashboard.

Drop down the fuse box cover and temporary remove to aid access. Wire the cable into the fuse box and then select an appropriate position for the green light and audible warning unit – the best place is probably on the side of the dashboard close to the interior light. Drill a hole and insert the light fitting and complete the connections.

Finally re-fit the coolant bottle and fill with antifreeze. As a test, use a pencil or similar object to push the magnet float towards the bottom of the bottle; this should activate the alarm.

LoLarm II costs £62.50 plus £5 postage and packing. Thanks to South Coast MG Rover for the installation work.