This WSM powerhead rebuild kit is for Mercury and Mariner 70-90 HP 3-cylinder looper powerheads using the bottom-guided configuration. Because a separate top-guided kit exists for this engine family, rod-guidance style should be confirmed before ordering.
Fitment
- Mercury/Mariner 70 HP 3-cylinder looper: 1987-1990
- Mercury/Mariner 75 HP 3-cylinder looper: 1990-1993
- Mercury/Mariner 80 HP 3-cylinder looper: 1987-1990
- Mercury/Mariner 90 HP 3-cylinder looper: 1987-1993
Technical Specifications
- WSM standard-size kit: 100-25-10
- 3-cylinder looper powerhead
- 3.375-inch standard bore
- Bottom-guided configuration
- A separate WSM 100-35-10 top-guided kit is used for top-guided applications in this engine family
Piston Size Options
- Standard
- .010 oversize
- .015 oversize
- .020 oversize
- .030 oversize
- .040 oversize
Measure the finished cylinder bore before selecting piston size.
Complete Kit Includes
- 3 WSM piston kits with rings, wrist pins, and clips
- Complete gasket kit: 1 head-cover gasket, 1 base gasket, 6 carburetor gaskets, 6 reed-block gaskets, 2 exhaust gaskets, lower end-cap and crank O-rings, 1 upper crank O-ring, 1 3.0-liter O-ring, 1 fuel-pump gasket, 1 upper crank oil seal, and 1 lower end-cap oil seal
- 1 upper main bearing, 2 center main bearings, and 1 lower main bearing
- 3 upper and 3 lower connecting-rod bearings
- 6 connecting-rod bolts
Fitment Note
Outboard applications can vary by horsepower, year, bore size, rod-guidance style, and model or serial range. Compare the fitment and technical details above with your engine before ordering.
Questions About This Product?
Have questions about this product? Email us at customerservice@marinepartswarehouse.com and include your motor information with your question.
