Fuel Tank Cap Replaces 510482078 531003399,51049-2091 for Husqvarna 125BT, 145BT, 155B, 155BT, H140B for Poulan: PP442, BP402LE Black

What It Is

This is a direct replacement fuel tank cap designed for Husqvarna and Poulan handheld trimmers, blowers, and brushcutters. It seals the fuel tank to prevent leaks and evaporative emissions, and it includes a built-in vent to maintain proper fuel flow.

Fitment & Compatibility

• Replaces OEM part numbers: 510482078, 531003399, and 51049-2091.
• Fits Husqvarna models: 125BT, 145BT, 155B, 155BT, H140B.
• Fits Poulan models: PP442, BP402LE.
• Before buying: Confirm your mower’s model number (stamped on the engine shroud or under the fuel cap). This cap is a universal fit for most Husqvarna/Poulan handhelds with a standard 1.25-inch cap opening, but measure your existing cap’s diameter (threads and outer rim) to be safe. It is an aftermarket replacement, not OEM Husqvarna, but matches OEM specs.

Key Things to Know

• Vent function is critical: This cap has a built-in vent. If your engine runs rough or stalls after a few minutes, the vent may be clogged. Clean it periodically with compressed air or replace the cap.
• Installation is tool-free: Just unscrew the old cap and screw on the new one by hand. No tools or sealant needed. Tighten until snug—over-tightening can crack the cap or strip the threads.
• Quality note: At $8.60, it’s a budget-friendly alternative to OEM ($12–15). Reviews mention it seals well and fits correctly, but a few users report the vent fails after a season of heavy use. Inspect the rubber gasket for cracks before each use.
• Check for debris: Old caps often have dirt or old fuel residue on the threads. Wipe the tank opening clean before installing the new cap to ensure a proper seal.

Should You Buy It

If you need a quick, affordable fix for a leaking or missing cap on a compatible Husqvarna or Poulan handheld, this is a solid choice. It’s cheap, easy to install, and works as intended for most users. For heavy commercial use or if you want OEM reliability, spend a few dollars more on the genuine Husqvarna part.