O.S. Engine OS21804200 Heatsink Head for 15RX engines, heatsink cylinder head accessory  [OS21804200]

Heatsink head for 15RX

This O.S. Engine heatsink head is an RC-scale replacement head designed around the 15RX designation in the product name to address cooling at the cylinder head. Its purpose is to increase surface area at the engine head to help dissipate heat during running and tuning on small RC engine setups.

Fit and compatibility are limited to engines identified by the 15RX head pattern in the product name, so confirm your engine uses the same head mount and bolt pattern before installation. This article does not invent additional compatible models, it uses the 15RX identifier as the compatibility reference provided in the product name.

Installation notes: remove the existing head per your engine’s service procedure, clean mating surfaces, position the heatsink head and tighten head screws evenly to the torque recommended by your engine manual. Use proper gaskets or sealing as required by the engine; avoid over‑tightening which can distort the head and reduce cooling efficiency.

Tuning role: the heatsink head is a passive cooling accessory intended to stabilise head temperature during prolonged runs and when adjusting ignition or carburetion settings. Expect more gradual temperature change under load, which can help with repeatable tuning, but do not rely on it as a substitute for correct fuel and needle settings.