Water Pump Impeller 6F5-44352-00 for Yamaha Mariner 40 HP Outboard 1990-1997 18-3088
Water Pump Impeller 6F5-44352-00 for Yamaha Mariner 40 HP Outboard 1990-1997 18-3088
Product Overview
Water pump impeller, a direct replacement part for Yamaha and Mariner 40 HP outboards built from 1990 to 1997. It replaces Yamaha 6F5-44352-00 and Mercury 99971M and 83397M, and crosses to Mallory 9-45606 and Sierra 18-3088. The impeller is 69.97 mm outside diameter, 22.12 mm tall, on a 16.24 mm hub, with 6 blades.
This is the rubber impeller inside the water pump on the lower unit. It turns with the driveshaft and pushes cooling water up to the powerhead, and it is the first part to fail when a motor sits between trips.
The blades are neoprene on a hardened nylon hub, and the drive is by key. Both the Yamaha and the Mariner versions of the 40 HP use the same pump, which is why one impeller covers both brands.
The fitment is one horsepower and one year range: Yamaha 40 HP, 1990 to 1997, in the C40 and CV40 model codes listed below. Check the model code on the cowling before ordering.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Water pump impeller |
| Yamaha Part Number | 6F5-44352-00 |
| Mercury Mariner Part Numbers | 99971M, 83397M |
| Mallory Cross Reference | 9-45606 |
| Sierra Cross Reference | 18-3088 |
| Fits | Yamaha and Mariner 40 HP outboards |
| Fits Years | 1990 to 1997 |
| Outside Diameter | 69.97 mm / 2.75 in |
| Inside Diameter | 16.24 mm / 0.64 in |
| Height | 22.12 mm / 0.87 in |
| Number Of Blades | 6 |
| Shaft Type | Key drive |
| Material | Neoprene rubber with hardened nylon hub |
| Package Contents | 1 x water pump impeller |
| Country of Origin | Taiwan |
| Net Weight | 75 g including packaging |
| Pack Size | 150 mm x 100 mm x 30 mm |
| Pack Size In Inches | 5.91 in x 3.94 in x 1.18 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| Yamaha | 6F5-44352-00 |
| Mercury | 99971M, 83397M |
| Mariner | 99971M, 83397M |
| Mallory | 9-45606 |
| Sierra | 18-3088 |
Compatible Engines
| Brand | Horsepower | Years | Model Codes |
|---|---|---|---|
| Yamaha | 40 HP | 1990 to 1997 | C40EL, C40ES, C40ML |
| Yamaha | 40 HP | 1990 to 1997 | C40MS, C40PL, CV40ELD |
| Mariner | 40 HP | 1990 to 1997 | Same pump as the Yamaha 40 HP |
What's Included
| Component | Size Or Number | Qty |
|---|---|---|
| Water pump impeller, 6 blades | 69.97 mm outside diameter, 6F5-44352-00 | 1 |
| Drive key | Not included, reuse the original | 0 |
| Pump housing | Not included | 0 |
| Gaskets | Not included | 0 |
Signs The Impeller Needs Replacing
| What You See | What It Means | What To Do |
|---|---|---|
| Tell tale weak or stops at idle | Blades worn or set | Fit the new impeller |
| Overheat warning at low speed | Pump not moving enough water | Fit the new impeller |
| Rubber scraps in the inlet screen | Impeller broken up | Fit the new impeller |
| Blades set in one direction | Rubber taken a set over winter | Fit the new impeller |
| Motor started dry on the muffs | Blades burnt and glazed | Fit the new impeller |
| Impeller spins on the shaft | Key missing or sheared | Fit the new impeller and key |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Read the model code off the motor and check it against the table above |
| 2 | Put the motor in gear, remove the propeller and drop the lower unit |
| 3 | Take the pump housing off and note which way the old blades point |
| 4 | Prise the old impeller off and take the key out of the shaft slot |
| 5 | Clean the pump plate and check the housing for deep grooves |
| 6 | Fit the key, then slide the impeller on with the blades trailing |
| 7 | Refit the housing and tighten the bolts evenly in a cross pattern |
| 8 | Turn the driveshaft by hand to check the impeller turns with the shaft |
| 9 | Run the motor on muffs and confirm a strong tell tale before you launch |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Sealed retail packaging |
Before You Buy
- Fits Yamaha 40 HP models C40EL, C40ES and C40ML from 1990 to 1997
- Fits Yamaha 40 HP models C40MS, C40PL and CV40ELD from 1990 to 1997
- Fits Mariner 40 HP outboards of the same years
- Replaces Yamaha 6F5-44352-00 and Mercury 99971M and 83397M
- Crosses to Mallory 9-45606 and Sierra 18-3088
- Impeller is 69.97 mm outside diameter, 22.12 mm tall, with 6 blades
- Key drive shaft, neoprene blades on a hardened nylon hub
- 75 g with packaging, box 150 mm x 100 mm x 30 mm
- 30-Day Easy Returns
Verfügbarkeit für Abholungen konnte nicht geladen werden
Boat Owners' Review
Before You Buy
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