Bell Housing Retainer Sleeve Ring 816607 18-1728 for MerCruiser Alpha One Gen II 1991 Up
Bell Housing Retainer Sleeve Ring 816607 18-1728 for MerCruiser Alpha One Gen II 1991 Up
Product Overview
Bell housing retainer sleeve ring for the MerCruiser Alpha One Gen II sterndrive, the aluminium part that traps the drive bellows flange in the bell housing. It replaces MerCruiser 816607 and Sierra 18-1728, it fits every Alpha One Gen II from 1991 on, and it ships as one flanged ring in a 170 mm x 180 mm x 30 mm pack at 55 g.
The ring sits in the bell housing where the drive bellows meets it. The bellows slides over the flange and the ring clamps it down, so the joint stays watertight while the drive is tilted and turned.
It is a part that gets replaced with the bellows rather than on its own. The ring corrodes and the flange edge pits, and a pitted flange will not seal a new bellows no matter how well the bellows is fitted.
On a sterndrive the bellows keeps lake or sea water out of the bell housing, where the gimbal bearing and the U-joint live. Water in there shows up as a rusty U-joint, a rough gimbal bearing, or gear oil leaking out of a housing that has been sitting wet.
Fitment covers the MerCruiser Alpha One Gen II sterndrive from 1991 onwards, which is the Gen II from its introduction through the current model years. Check the drive model and the serial number before ordering.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Bell housing retainer sleeve ring |
| MerCruiser Part Number | 816607 |
| Sierra Number | 18-1728 |
| Material | Aluminium, flanged |
| Application | Drive bellows flange, bell housing |
| Fits | MerCruiser Alpha One Gen II sterndrive, 1991 and up |
| Quantity | 1 ring |
| Net Weight | 55 g including packaging |
| Pack Size | 170 mm x 180 mm x 30 mm |
| Pack Size In Inches | 6.69 in x 7.09 in x 1.18 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| MerCruiser | 816607 |
| Sierra | 18-1728 |
Compatible Engines
| Engine / Drive | Years | Position |
|---|---|---|
| MerCruiser Alpha One Gen II sterndrive | 1991 and newer | Drive bellows flange, bell housing |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Aluminium flanged sleeve ring | Replaces MerCruiser 816607 and Sierra 18-1728 | 1 |
| Drive bellows | Not included, order it separately | 0 |
| Bell housing gasket | Not included, replace it if the housing comes off | 0 |
Key Features
| Feature | Detail |
|---|---|
| OEM replacement | Built to the MerCruiser 816607 size |
| Aluminium flange | Clamps the bellows against the bell housing |
| Cross referenced | Also listed as Sierra 18-1728 |
| Alpha One Gen II | Fits the Gen II drive from 1991 on |
| Fits with a new bellows | Replace both, the flange pits with age |
| Small and light | 55 g, 170 mm x 180 mm x 30 mm pack |
Packing Dimensions
| Measure | Millimetres | Inches |
|---|---|---|
| Pack length | 170 mm | 6.69 in |
| Pack width | 180 mm | 7.09 in |
| Pack height | 30 mm | 1.18 in |
| Weight with packaging | 55 g | 1.94 oz |
Signs The Ring Needs Replacing
| What You See | What It Means | Action |
|---|---|---|
| Water in the bell housing | Bellows joint not sealing | Fit a new ring and bellows |
| Rusty U-joint or gimbal bearing | Water has been getting in | Fit a new ring and bellows, check the bearing |
| Pitted or corroded flange edge | Ring will not seal a new bellows | Fit a new ring |
| Bellows slipping off the flange | Ring not clamping any more | Fit a new ring |
| Gear oil in the bell housing | Bellows failed at the flange | Fit a new ring and bellows |
| Bellows being replaced | Ring is a fit-once part | Fit a new ring at the same time |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the drive model and serial number |
| 2 | Take the drive off and drain the bell housing |
| 3 | Cut the old bellows off and take the old ring out |
| 4 | Clean the bell housing face and check it for corrosion |
| 5 | Fit the new bellows over the flange of the new ring |
| 6 | Seat the ring in the bell housing squarely |
| 7 | Refit the drive and check the bellows for kinks |
| 8 | After the first trip, check the bell housing for water |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Pack, 170 mm x 180 mm x 30 mm |
Before You Buy
- Replaces MerCruiser 816607
- Also crosses to Sierra 18-1728
- Fits the MerCruiser Alpha One Gen II sterndrive from 1991 on
- Aluminium flanged sleeve ring, one per pack
- 55 g with packaging, pack 170 mm x 180 mm x 30 mm
- Order the drive bellows separately
- Check the drive model and serial number before ordering
- 30-Day Easy Returns
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