The COGENG K311686/57588 Engine Oil Pressure Switch is a high-quality, direct OEM replacement switch specifically designed for Case IH and David Brown tractors, including the classic David Brown 770 model. This critical engine component monitors engine oil pressure and activates the oil pressure warning light on the dashboard when pressure drops below a safe threshold.
Unlike a pressure sensor which provides continuous variable readings, a pressure switch is a simple on/off device. When engine oil pressure falls below a preset level (typically 5–10 PSI), the switch closes (or opens) an electrical circuit, illuminating the warning light to alert the operator of a potential lubrication problem. This simple but vital function helps prevent catastrophic engine damage caused by low oil pressure.
The David Brown 770 is a legendary tractor produced from 1965 to 1971, known for its ruggedness and reliability. These tractors are still in active use on farms worldwide, and maintaining their original systems with quality replacement parts is essential.
Manufactured under ISO9001 certified processes, the COGENG K311686/57588 features a durable iron/brass housing and premium rubber seals to withstand the demanding environment of agricultural operations – constant vibration, temperature extremes, and exposure to engine oil, fuel, and debris. Each unit undergoes 100% testing for switching accuracy, sealing integrity, and response time.
Why Choose COGENG K311686/57588?
| Feature | Benefit |
|---|---|
| ✅ Direct OEM Replacement | Plug-and-play for David Brown 770 |
| ✅ Simple On/Off Switching | Activates warning light at low pressure |
| ✅ Preset Pressure Threshold | Typically 5–10 PSI activation |
| ✅ Durable Construction | Iron/brass housing – no plastic |
| ✅ Leak-Proof Design | Premium rubber seal pre-installed |
| ✅ Single Terminal Design | Easy to connect to existing wiring |
| ✅ In Stock | Ready to ship immediately |
| ✅ ISO9001 Certified | Consistent quality you can trust |
| Parameter | Details |
|---|---|
| Product Name | Engine Oil Pressure Switch |
| Part Numbers | K311686, 57588 |
| Compatible Brands | Case IH, David Brown |
| Compatible Tractor Models | David Brown 770 |
| Compatible Engine | David Brown / Case IH diesel engines |
| Material | Iron + Rubber + Brass |
| Packing | PP bag inside, carton box outside |
| Payment Terms | Western Union, L/C, T/T, MoneyGram, D/A, D/P |
| MOQ | Acceptable trial order (1 piece accepted) |
| Shipping Mode | By air, by sea, by express (FedEx, UPS, DHL, TNT, etc.) |
| Place of Origin | Guangdong, China |
| Brand Name | COGENG |
| Certification | ISO9001 |
| Stock Status | ✅ In Stock |
| Supply Capacity | 500 PCS |
| Component Name | Quantity | Description |
|---|---|---|
| Oil Pressure Switch | 1 | Complete assembly, ready to install |
| Rubber / Copper Sealing Washer | 1 | Pre-installed on threaded base |
| Protective Plastic Cap | 1 | For shipping protection only |
| Installation Quick Guide | 1 | Basic instructions |
This oil pressure switch is specifically designed for the following Case IH and David Brown tractors:
| Model | Manufacturer | Typical Year Range | Engine |
|---|---|---|---|
| David Brown 770 | David Brown (Case IH) | 1965–1971 | David Brown 3.6L diesel |
Additional compatible models (verify before purchase):
| Model | Compatibility Level | Notes |
|---|---|---|
| David Brown 880 | ✅ Compatible | Same engine family |
| David Brown 885 | ✅ Compatible | Same engine family |
| David Brown 990 | ✅ Compatible | Same switch design |
| David Brown 995 | ✅ Compatible | Same switch design |
| David Brown 1200 | ✅ Compatible | Later model – check thread |
| Case IH 585 | ✅ Compatible ⚠️ Similar | Check thread type |
| Case IH 685 | ✅ Compatible ⚠️ Similar | Check thread type |
| Case IH 885 | ✅ Compatible ⚠️ Similar | Check thread type |
Important: The David Brown 770 is a classic tractor (1965-1971). Many other David Brown models from the same era (880, 885, 990, 995, 1200, 1210, 1212, 1410, 1412) use the same or similar oil pressure switch.
| Parameter | David Brown 770 |
|---|---|
| Production years | 1965–1971 |
| Engine | David Brown 3.6L (219 cu in) 3-cylinder diesel |
| Engine type | Naturally aspirated, indirect injection |
| Horsepower | 60 HP (45 kW) PTO / 52 HP (39 kW) drawbar |
| Transmission | 12 forward / 4 reverse (Draft-o-matic) |
| Hydraulic system | 9.5 GPM (36 L/min) |
| Electrical system | 12V (negative ground typical) |
| Weight | 4,400 lbs (2,000 kg) |
Normal Oil Pressure Ranges (David Brown 770 Diesel Engine):
| Condition | Pressure (PSI) | Pressure (bar) | Switch Status |
|---|---|---|---|
| Hot idle (600-700 RPM) | 10–20 | 0.7–1.4 | Warning light OFF |
| Cold idle | 30–50 | 2.1–3.4 | Warning light OFF |
| Working RPM (1500–2200 RPM) | 35–55 | 2.4–3.8 | Warning light OFF |
| Low pressure (warning light ON) | Below 7–10 | Below 0.5–0.7 | Switch activates |
✅ Direct OEM replacement for:
Case IH part number: K311686
David Brown part number: K311686
Aftermarket cross: 57588
✅ Designed for:
David Brown 770 tractor (1965–1971)
Also fits many David Brown models (880, 885, 990, 995, 1200, etc.)
Case IH tractors of the same era
✅ Engine compatibility:
David Brown 3-cylinder diesel engine (3.6L / 219 cu in)
David Brown 4-cylinder diesel engines (similar era)
✅ Electrical specifications:
Normally closed (N.C.) or normally open (N.O.) – verify
Activation pressure: Typically 7–10 PSI (0.5–0.7 bar)
Single terminal design (switch closes to ground)
Compatible with 12V electrical systems
✅ Mechanical specifications:
Thread size: 1/8-27 NPT or 1/8 BSP (British Standard Pipe)
Hex size: 14mm, 17mm, or 19mm (confirm)
Sealing washer: Copper or rubber (pre-installed)
⚠️ Before purchasing, please verify:
| Check Item | Details |
|---|---|
| Tractor model | David Brown 770 or other David Brown model |
| Thread type | NPT or BSP – British tractors often use BSP |
| Switch type | Normally closed (N.C.) or normally open (N.O.) |
| Activation pressure | Confirm with original switch |
| Terminal type | Spade terminal or threaded post |
❌ NOT compatible with:
Modern Case IH tractors (different electrical systems-verify)
David Brown 770 gasoline engines (different – verify)
Engines requiring a pressure sensor (variable output) rather than a switch (on/off)
24V electrical systems (unless verified)
Metric thread engines (British tractors typically use BSP)
Installation decomposition diagram
Tools Required:
| Tool | Purpose |
|---|---|
| 14mm, 17mm, or 19mm wrench / socket | Remove and install switch (size varies) |
| Torque wrench (recommended) | Achieve 10–15 Nm spec |
| Small pliers | Remove wire if stuck |
| Clean rag | Wipe mounting surface |
| Engine oil (clean) | Lubricate threads/washer |
| Flashlight | Locate switch |
Installation Tips:
⚠️ Engine must be cool – hot oil can cause burns
🧹 Clean mounting surface – debris can prevent proper sealing
💧 Apply clean engine oil to threads and sealing washer before installation
🔧 Do NOT overtighten – switch body can crack or threads can strip (BSP/NPT taper)
🔌 Ensure wire connection is secure – loose wire causes intermittent warning light
🔍 Test before reassembling any covers
📊 If warning light stays on after starting, check actual oil pressure with mechanical gauge
Testing the Circuit:
| Condition | Switch State | Warning Light |
|---|---|---|
| Key ON, engine OFF | Closed (to ground) | ON |
| Engine running (good pressure) | Open | OFF |
| Engine running (low pressure) | Closed (to ground) | ON |
Q1: What is the difference between an oil pressure switch and an oil pressure sensor?
A:
| Feature | Pressure Switch | Pressure Sensor |
|---|---|---|
| Output | On/Off (binary) | Variable (analog) |
| Function | Turns light on/off at set pressure | Sends continuous pressure reading |
| Wiring | Single wire (ground) | 2-3 wires (power, ground, signal) |
| Application | Warning light only | Gauge, ECU, display |
The K311686/57588 is a SWITCH (on/off) – not a sensor.
Q2: What are the symptoms of a failing oil pressure switch on a David Brown 770?
A: Common signs include:
Oil pressure warning light stays on even when engine is running (oil pressure normal)
Oil pressure warning light never comes on when key is ON (engine off)
Warning light flickers intermittently
Oil leak from switch body or base
Warning light comes on too early or too late
No warning light at all (bulb could be burned out – check first)
Q3: How do I test if my oil pressure switch is bad?
A: Perform these checks:
Test 1 – Warning light function (engine off):
Turn key to ON (do not start engine)
Oil pressure warning light should be ON
If light is OFF, bulb may be burned out OR switch is stuck open
Test 2 – Warning light function (engine running):
Start engine
Oil pressure warning light should turn OFF within a few seconds
If light stays ON, check actual oil pressure with mechanical gauge
Test 3 – Continuity test (switch removed):
Remove switch from engine
Use multimeter on continuity setting
With no pressure: Should show continuity (closed) – warning light would be ON
Apply light pressure (push with finger or air): Should show no continuity (open)
Q4: Is this a genuine Case IH / David Brown OEM part?
A: No. This is a COGENG aftermarket replacement manufactured to meet or exceed OEM specifications. It is a direct replacement for Case IH part number K311686 and aftermarket number 57588.
Q5: Will this switch fit my David Brown 770?
A: Yes – this switch is specifically designed for the David Brown 770.
Q6: What is the activation pressure of this switch?
A: The switch typically activates (closes to ground) at 7–10 PSI (0.5–0.7 bar) . This is the standard threshold for David Brown tractors.
Q7: Is this switch normally closed or normally open?
A: Most David Brown oil pressure switches are normally closed (N.C.) – meaning the switch is closed (light ON) when there is no oil pressure (engine off), and opens (light OFF) when oil pressure rises above the threshold (engine running).
Q8: What thread type does this switch use – NPT or BSP?
A: David Brown tractors (British-made) typically use 1/8 BSP (British Standard Pipe) thread. However, some replacement switches use 1/8-27 NPT. Verify your original switch thread type before ordering.
How to tell the difference:
NPT: Tapered thread, requires sealant or tape (not recommended)
BSP: Parallel thread, uses sealing washer (copper or rubber)
COGENG switches include a sealing washer – suitable for BSP ports.
Q9: Is this switch in stock for immediate shipping?
A: Yes – COGENG maintains stock of 500+ units. Orders ship within 24–48 hours.
Q10: What is the warranty?
A: COGENG provides a 6-month warranty against manufacturing defects.
Q11: How long does shipping take?
A:
Express (DHL/FedEx/UPS/TNT): 3–7 business days worldwide
Air freight: 7–12 days
Sea freight: 20–40 days
Q12: Do I need any special tools to install this switch?
A: No. A standard wrench (14–19mm) is all you need.
Q13: Do I need to use thread sealant?
A: No – the sealing washer provides the oil seal. If your engine port is BSP (parallel thread), the washer is sufficient. If NPT (tapered), use minimal thread sealant – but never use PTFE tape on oil pressure switches (can cause poor ground connection).
Q14: Why does my warning light stay on after starting the engine?
A: Possible causes:
Low oil pressure (check with mechanical gauge – serious issue)
Faulty switch (stuck closed)
Wire shorted to ground (inspect wiring)
Wrong switch type (normally closed vs normally open)
Q15: Can I install this switch myself?
A: Yes, with basic mechanical skills (10–15 minutes). If uncomfortable, professional installation is recommended.
Q16: How do I place a trial order?
A: Contact your COGENG distributor directly. MOQ is 1 piece for trial orders – we welcome first-time buyers.
| Order Option | Details |
|---|---|
| Minimum Order Quantity (MOQ) | 1 piece (trial order accepted) |
| Stock Status | ✅ 500+ pieces in stock |
| Lead Time | Ships within 24–48 hours |
| Payment Methods | Western Union, L/C, T/T, MoneyGram, D/A, D/P |
| Shipping Methods | FedEx, UPS, DHL, TNT, air freight, sea freight |
| Packaging | PP bag inside, carton box outside |
How to Order in 3 Simple Steps:
| Step | Action |
|---|---|
| 1️⃣ | Send inquiry with your tractor model (David Brown 770) |
| 2️⃣ | Confirm thread type (BSP or NPT) if known |
| 3️⃣ | Place order – we send invoice + tracking number within 24 hours |
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