The Recmar REC30530-PNA-003 is a high quality knock sensor designed as a direct replacement for Honda outboard engines that use OEM part number 30530-PNA-003. Fitted to BF135A4 and BF150A4 models, this detonation sensor detects harmful engine knock and sends a signal to the ECU so ignition timing can be corrected, improving reliability and protecting internal components.

Key features

• Direct replacement knock sensor for Honda BF135A4 and BF150A4 outboards

• Recmar reference: REC30530-PNA-003

• Replaces Honda OEM: 30530-PNA-003

• Detects detonation and sends feedback to the engine ECU

• Helps prevent piston, valve and head damage caused by prolonged knock

• Contributes to smoother running and improved fuel efficiency

• Marine grade construction suitable for the outboard environment

• Designed as an easy, direct fit into the original mounting position

Compatibility

This Recmar knock sensor is suitable for the following Honda outboard engines:

• Honda BF135A4

• Honda BF150A4

It replaces Honda OEM part number 30530-PNA-003 used on these models. Always check your engine serial number and parts book to confirm compatibility before ordering.

What does a knock sensor do

The knock sensor is bolted to the engine block and listens for the specific vibration signature of detonation. When knock is detected, the sensor sends a signal to the ECU, which retards ignition timing to bring combustion back under control. This protects pistons, rings, bearings and the cylinder head from long term damage and helps the engine run more smoothly under load.

Typical symptoms of a failing knock sensor

• Engine warning light or fault code relating to knock detection

• Noticeable loss of power or poor acceleration

• Rough running under load or at certain rpm

• Increased fuel consumption

These symptoms can also be caused by other faults, so diagnosis should always follow the manufacturer guidance.

Technical details

• Brand: Recmar

• Product type: Outboard knock sensor / detonation sensor

• Recmar code: REC30530-PNA-003

• OEM cross reference: Honda 30530-PNA-003

• Application: Honda BF135A4, BF150A4 outboard engines

• Unit of sale: Each

Installation notes

Installation is normally straightforward: the sensor fits into the existing threaded position on the block and connects to the original wiring plug. Always follow the Honda workshop manual torque settings and procedures, and clear any stored fault codes with suitable diagnostic equipment after fitting.