Volvo Penta OEM Oil Pressure Sensor 866833 | 0–10 Bar | Replaces 843231 | TAMD TMD AD Diesel

Volvo Penta OEM Oil Pressure Sensor — Part 866833

• Part Number: 866833
• Brand: Volvo Penta (Genuine OEM)
• Official Product Type: Engine Sensors & Senders — Oil Pressure Sensor / Sender
• System: Engine lubricating-oil pressure monitoring — electrical / instrumentation system
• Pressure Range: 0–10 bar (approx. 0–145 psi)
• Replaces: 843231 (earlier Volvo Penta oil pressure sender)
• Weight: approx. 0.136 kg (0.3 lb)

Range matters: The 866833 is rated for 0–10 bar. Volvo Penta used several visually similar oil pressure senders with different pressure ranges. Installing a sender with the wrong range will produce an incorrect gauge reading even if the threads fit. Always match by part number, engine serial number, and instrument range — not by appearance alone.

What It Does

The 866833 is the genuine OEM engine oil pressure sensor used on a wide range of classic Volvo Penta marine and industrial diesel engines. It sends engine oil-pressure information to the vessel’s pressure gauge or monitoring instrumentation and is rated for a 0–10 bar (approximately 0–145 psi) pressure range. Volvo Penta 866833 replaces earlier oil pressure sender 843231 and appears in the electrical-system and instrumentation diagrams for numerous AD, AQAD, TAMD, TMD, and related Volvo Penta diesel families. Note that this is the oil-pressure sender (gauge signal), which is separate from the oil-pressure warning switch used on many of the same engines.

Compatible Applications

Confirm fitment by engine model and serial number and the specific Volvo Penta electrical-system diagram before ordering. Volvo Penta used different oil-pressure sensors during production changes, and sensor range and instrument compatibility must match the original engine configuration.

AD / AQAD Series

• AD30A, AD31A, AD31B, AD41A
• AQAD30A, AQAD40A, AQAD40B, AQD40A
• AQD70CL, AQD70D

TAMD Series

• TAMD30A, TAMD31A, TAMD31B
• TAMD40A, TAMD40B, TAMD41A
• TAMD60A, TAMD60B, TAMD60C
• TAMD61A, TAMD62A
• TAMD70C, TAMD70D, TAMD70E
• TAMD71A, TAMD71B, TAMD72A, TAMD72P-A, TAMD72WJ-A, TAMD73P-A
• TAMD102A, TAMD102D
• TAMD121C, TAMD121D, TAMD122A
• Selected TAMD16-series engines

TMD / Industrial Families

• TMD30A, TMD31A, TMD31B
• TMD40A, TMD40B, TMD40C, TMD41A
• TMD70C
• Selected TD61 / TD71
• Selected TID61 / TID71

Not sure it fits? Send us your Volvo Penta engine model and serial number before ordering.

Related Instrumentation Components

The 866833 is the oil-pressure sender only. The following components are commonly associated with the Volvo Penta oil-pressure monitoring system and are sold separately:

• 843231 — Earlier Volvo Penta oil pressure sender; superseded by 866833
• 863169 — Oil pressure monitor / warning switch (separate component on applicable engines)
• 873601 — Associated cable on selected configurations
• 942490 — T-nipple used on selected installations
• 947624 — Gasket used with associated sensor fittings on some engines
• 866834 / 866835 — Different pressure sensors used on other Volvo Penta configurations (different range)

Part Numbers & Cross-References

• 866833 — Current Volvo Penta OEM part number
• 843231 — Earlier Volvo Penta reference; superseded by 866833
• VDO 360-081-032-003C — Commonly referenced aftermarket equivalent (use OEM 866833 for verified fitment)

When to Replace

Consider replacing the oil pressure sensor when:

• Oil pressure gauge readings are erratic or intermittent
• The gauge reads incorrectly after actual mechanical oil pressure has been verified with a test gauge
• No oil pressure signal reaches the instrument
• The sensor body is leaking engine oil at the pressure port
• Electrical terminals are corroded or damaged
• The sender has an internal electrical fault confirmed by wiring and gauge checks

Always verify actual engine oil pressure mechanically before assuming a low-pressure indication is caused by the sender. A failed sender should not be confused with a genuine low oil-pressure condition.

Service Interval

No fixed replacement interval — replace on condition. Inspect the sensor body, threads, and electrical connections at each annual engine service. On diesel engines operated in harsh marine environments, thread corrosion and connector degradation are the most common failure modes. If the oil pressure gauge becomes intermittent or erratic, test the wiring and gauge before replacing the sender to avoid unnecessary parts replacement.

Installation Notes

• Confirm 866833 is the correct 0–10 bar oil pressure sender for your engine by model, serial number, and electrical-system diagram before installing — the pressure range must match the original sensor and instrument
• Do not substitute 866834, 866835, or another sender with a different pressure range — an incorrect range will produce a false gauge reading
• Inspect the electrical connector, terminals, and harness while the sensor is out and repair any corrosion before fitting the replacement
• Clean the pressure port area before installation
• Inspect the mating fitting or T-piece (942490 where applicable) for damage or corrosion
• Use thread sealant only where specified by the Volvo Penta service procedure for the applicable engine
• Verify that the gauge responds correctly after installation and that oil pressure readings are within the expected operating range

Technical FAQ

Q: What is the difference between the oil pressure sender and the oil pressure warning switch?
The oil pressure sender (866833) provides a continuous variable signal to the oil pressure gauge on the helm. The oil pressure warning switch (863169 on applicable engines) is a separate on/off switch that triggers a warning alarm or light when oil pressure drops below a threshold. Both may be present on the same engine and are not interchangeable.

Q: My oil pressure gauge reads incorrectly — is the sender definitely faulty?
Not necessarily. An incorrect gauge reading can be caused by a faulty sender, a wiring fault, a faulty gauge, or in some cases an actual oil pressure problem. Verify actual mechanical oil pressure with a test gauge first, then check the wiring and gauge before replacing the sender.

Q: Can I use an aftermarket sender instead of 866833?
Some aftermarket equivalents reference VDO 360-081-032-003C for this application. For verified OEM fitment and instrument compatibility, 866833 is the correct Volvo Penta part. Confirm the pressure range and electrical characteristics match before substituting any aftermarket sender.

Q: Does 866833 fit all TAMD engines?
No. 866833 is specified for selected TAMD, TMD, AD, and AQD engine families within certain serial number ranges. Some engines in those same families use a different sensor depending on production range and instrument system. Confirm by engine model and serial number using the Volvo Penta electrical-system diagram.

Parts Desk Insights

The most critical detail with 866833 is the 0–10 bar pressure range. Volvo Penta produced several visually similar oil pressure senders for different pressure ranges and instrument types, and the wrong sender will give an incorrect reading even if it installs in the same port. When a customer reports an erratic or incorrect oil pressure reading, the wiring and gauge should be checked before the sender is replaced — a damaged connector or corroded wire is a more common cause of intermittent readings than a failed sender body. If the sender is confirmed faulty and the engine serial number falls in a range that used 843231 originally, 866833 is the current OEM replacement.