Fuel Pump 803529T06 3H6-04000-1 for Tohatsu Nissan Mercury Mariner 4 5 6 8 9.8 HP 4-Stroke Outboard — United Kingdom Local Warehouse
Fuel Pump 803529T06 3H6-04000-1 for Tohatsu Nissan Mercury Mariner 4 5 6 8 9.8 HP 4-Stroke Outboard — United Kingdom Local Warehouse
Product Overview
Fuel pump part for Tohatsu, Nissan, Mercury and Mariner four stroke outboards from 4 HP to 9.8 HP, with the wider range also covering the 15 HP and 25 HP four stroke blocks. It replaces Tohatsu and Nissan 3H6-04000-1, 3H6040000M through 3H6040007M, and Mercury 803529T06, 803529T03 and 803529T. Kept in our United Kingdom local warehouse.
These small four strokes use a mechanical pump driven off the camshaft or the crankcase pulse, and the pump is often the last thing checked when an outboard starts cutting out. A diaphragm that has gone hard still pumps at idle on a cold motor, then loses delivery once the fuel bowl is working hard, which reads as a fuel starvation problem that a carburettor clean never fixes.
Look for fuel weeping from the pump body, a strong petrol smell in the cowling, or a motor that needs the primer bulb pumped to keep running. Fit a new pump rather than a rebuild kit on these small blocks, and check the fuel line and primer bulb at the same time, because a perished bulb pulls air and mimics a failing pump.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Mechanical fuel pump |
| Engine | Tohatsu, Nissan, Mercury and Mariner four stroke outboard |
| Horsepower | 4 HP to 9.8 HP, plus 15 HP and 25 HP blocks |
| Drive | Camshaft or crankcase pulse, as original |
| Quantity | 1 fuel pump |
| Country of Origin | Taiwan |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| Tohatsu | 3H6-04000-1, 3H6-04000-3, 3H6-04000-7 |
| Tohatsu | 3H6040000M, 3H6040001M, 3H6040002M |
| Tohatsu | 3H6040003M, 3H6040004M, 3H6040007M |
| Nissan | 3H6-04000-1, 3H6040007M |
| Mercury | 803529T06, 803529T03, 803529T02 |
| Mercury | 803529T1, 803529T |
Compatible Engines
| Brand | Horsepower | Stroke |
|---|---|---|
| Tohatsu | 4HP | Four stroke |
| Tohatsu | 5HP | Four stroke |
| Tohatsu | 6HP | Four stroke |
| Tohatsu | 8 HP | Four stroke |
| Tohatsu | 9.8 HP | Four stroke |
| Nissan | 4HP | Four stroke |
| Nissan | 5HP | Four stroke |
| Nissan | 6HP | Four stroke |
| Nissan | 8 HP | Four stroke |
| Nissan | 9.8 HP | Four stroke |
| Mercury | 4 HP | Four stroke |
| Mercury | 5 HP | Four stroke |
| Mercury | 6 HP | Four stroke |
| Mariner | 4 HP | Four stroke |
| Mariner | 5 HP | Four stroke |
| Mariner | 6 HP | Four stroke |
| Mercury and Mariner | 15HP, 25 HP | Four stroke blocks using this pump body |
Signs the Fuel Pump Has Failed
| Symptom | What It Points To |
|---|---|
| Motor dies at speed, restarts after priming | Pump diaphragm not delivering |
| Needs the primer bulb squeezed to run | Pump weak or drawing air |
| Fuel weeping from the pump body | Diaphragm split, replace the pump |
| Strong petrol smell under the cowling | Seep from the pump or the hoses |
| Black spark plugs after a run | Rich mixture from a leaking diaphragm |
| Hard starting when cold | Low fuel delivery at cranking speed |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Disconnect the battery and close the fuel tap |
| 2 | Note the inlet and outlet hose positions before removal |
| 3 | Plug or clamp the fuel line to stop spillage |
| 4 | Remove the two mounting bolts and lift the pump clear |
| 5 | Check the old gasket face and clean it before fitting |
| 6 | Fit the new pump with a new gasket, do not over torque |
| 7 | Open the fuel tap and prime with the bulb, check for leaks |
| 8 | Run the motor and check the pump body stays dry |
What's Included
| Component | Qty |
|---|---|
| Fuel pump | 1 |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Shipping from United Kingdom
| Destination | Warehouse | Note |
|---|---|---|
| United Kingdom | United Kingdom local warehouse | Domestic delivery, no import duty |
| Ireland | United Kingdom local warehouse | Short transit, customs may apply |
| EU destinations | United Kingdom local warehouse | Customs cleared on arrival |
Before You Buy
- Confirm the outboard is a four stroke, not the two stroke model
- Check the number on the old pump, 803529T06 and 3H6-04000-1 are the common ones
- Check the primer bulb and fuel hose for air leaks at the same time
- Fit a new gasket, do not reuse the old one
- Check for leaks with the fuel tap open before starting
- Check the fuel filter if the motor still runs lean
- 30-Day Easy Returns
- Ships from our United Kingdom local warehouse
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