Engine Rebuild Kit Standard
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Compatible Applications
| Brand | Application | Engine Type | Application Notes |
|---|---|---|---|
| Mercury | 225 DFI 3.0L | 2-Stroke Outboard | Serial range OT599000-Up |
What is Included
| Qty | Included Part | Part Number |
|---|---|---|
| 3 | Pro Piston Kit Std. Port | N9100P |
| 3 | Pro Piston Kit Std. Starboard | N9100S |
| 12 | Rod Bolt (Torque to 30 ft-lb) | RB9000 |
| 6 | Wrist Pin Bearing w/ Washers | WP70-1 |
| 6 | Caged Rod Bearing | 012-1 |
| 2 | Center / Upper Main Bearing | 050 |
| 1 | Crankshaft Seal Kit | 2018 |
| 1 | Lower Main Ball Bearing | 308 |
| 1 | Powerhead Gasket Kit | 4312-3 |
| 1 | Upper Main Bearing | 816 |
| 6 | O-Ring, Cylinder Bore Seal | 4391 |
This is a standard-bore kit
The pistons are standard size (3.625"), for cylinders that are still within factory specification. If your cylinders are worn or scored and need to be bored, choose the matching oversize kit instead. Have your machine shop measure the bores before ordering.
What This Kit is Used For
This Pro Marine engine rebuild kit supplies the pistons, bearings, seals, and gaskets needed to rebuild the powerhead on Mercury 225 DFI 3.0L two-stroke outboards, in a standard-bore configuration.
Key Features and Benefits
- Engine rebuild kit for Mercury 225 DFI 3.0L
- Includes 6 Pro standard-bore pistons (3 port, 3 starboard)
- Includes wrist pin, rod, and main bearings plus new rod bolts
- Includes crankshaft seals, cylinder bore O-rings, and powerhead gasket kit
Kit Details
- Kit Part Number: 9100-7
- Manufacturer: Pro Marine (Aftermarket)
- Engine Type: 2-stroke, 6-cylinder
- Piston Size: Standard
- Bore: 3.625"
- Not Included: Crankcase sealant and needle bearing assembly grease
FAQ
What engines does this kit fit?
This kit fits Mercury 225 DFI 3.0L two-stroke outboards. Confirm your model and serial number before ordering.
Do I need to bore my cylinders?
No, as long as your cylinders are within factory specification. If they are worn or damaged, they will need to be bored and you will need an oversize kit.
Why are there port and starboard pistons?
This engine uses side-specific pistons, so the kit includes 3 of each. Install each piston on its matching cylinder bank.
Is crankcase sealant included?
No. Crankcase sealant and needle bearing assembly grease are sold separately.
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