Which genoa track and cars are typically fitted on a Hallberg-Rassy Monsun 31?

The Hallberg-Rassy Monsun 31 was factory-fitted with either 25mm (1-inch) or 32mm (1¼-inch) Lewmar T-track and basic pin-stop genoa cars. If your track remains structurally sound, you can slide on modern Lewmar or Barton replacement cars, but severely corroded tracks require full replacement using through-bolted marine-grade aluminium extrusions.

Identifying Original Hardware

Between 1974 and 1982, Hallberg-Rassy sourced deck hardware primarily from Lewmar. Most Monsun 31 hulls feature standard silver-anodised Lewmar T-track mounted on the side decks. Take a pair of vernier calipers and measure across the top flat section of the 'T' to determine your exact size. It will measure either 25mm (Size 1) or 32mm (Size 2). Countersunk machine screws spaced at 100mm intervals fasten the track to the deck.

Over four decades of saltwater exposure, the original anodising wears thin and leaves a pitted grey surface. You can save the track if the corrosion remains purely cosmetic and the edges stay intact. You must replace the entire extrusion if the track bends, shows deep pitting or causes the cars to snag.

Replacement Genoa Car Options

Upgrading the cars on a salvageable track improves sail trim. You have two main routes depending on your budget and sailing style:

• Direct pin-stop replacements: Barton Marine manufactures composite and aluminium T-track cars for a simple cruiser setup. A Barton 32mm genoa car with a plunger stop costs around £85. Modern Lewmar Size 1 or Size 2 pin-stop cars drop straight onto the original track and cost roughly £140 to £180 each.
• Towable genoa cars: A towable system lets you adjust the car position from the cockpit under load. This requires a car with control line sheaves, track end-fittings with blocks and cam cleats routed aft. Lewmar and Harken offer towable retrofit kits for 25mm and 32mm T-track. Expect to spend upwards of £500 per side for the complete setup.

Always measure your track thickness (the vertical height of the 'T' lip) before ordering to ensure the new car sliders slide freely. Some early 1970s tracks have a thicker lip than modern extrusions. This requires a light sanding of the car's nylon inserts for a proper fit.

Removing Corroded Track

Removing a 40-year-old genoa track proves difficult because the stainless steel countersunk bolts galvanically weld themselves to the aluminium track. You need an impact driver, a heavy hammer and a butane torch to break the bond. Apply heat directly to the bolt heads to break the sealant grip. Keep a wet rag nearby to protect the gelcoat from scorching.