Rainier Parts

Rainier Parts Grass Trimmer Carb Rebuild Kit ZAMA RB100 for STIHL HS45 FS55 FS38 BG45 with Diaphragm Gasket Primer

$15.99

Out of stock

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About this part

Keep your grass trimmer running smoothly with Rainier Parts’ Carburetor Rebuild Kit for ZAMA RB-100. Designed for popular STIHL models, including HS45, FS55, FS38, and BG45 carburetors, this kit helps restore precise fuel metering, reliable starts, and steady idle performance.

  • Compatibility: Fits ZAMA RB-100 carburetors used on STIHL HS45, FS55, FS38, and BG45 trimmers.
  • Complete rebuild kit: Includes 4 diaphragms and 9 additional parts for a full carburetor refresh.
  • Quality diaphragms & gaskets: Durable, fuel‑resistant components that restore sealing and fuel metering accuracy.
  • Primer bulb included: Ensures proper priming for easier starting and consistent fuel delivery.
  • Color note: Real item color may differ slightly from the photos due to lighting and monitor settings.

This rebuild kit addresses the most common carburetor wear after extended use—the diaphragm can become brittle or rupture, causing erratic idling or hard starts. Replacing the diaphragm, gaskets, and the primer bulb with this kit brings back smooth throttle response and dependable starts, without the need to replace the entire carburetor. It’s an excellent, cost‑effective solution for DIY enthusiasts, small repair shops, or service technicians maintaining lawn equipment fleets.