Transom Bellows Seal Kit for MerCruiser Alpha One Gen II — 30-803099T1 | GH Marine
Transom Bellows Seal Kit for MerCruiser Alpha One Gen II — 30-803099T1 | GH Marine is backordered and will ship as soon as it is back in stock.
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Transom Bellows Seal Kit for MerCruiser Alpha One Gen II — 30-80309...
Transom Bellows Seal Kit for MerCruiser Alpha One Gen II — 30-803099T1 | GH Marine is backordered and will ship as soon as it is back in stock.
GH MARINE / BELLOWS & RELATED PARTS
About this part
This transom bellows seal repair kit is intended for transom bellows and seal service on MerCruiser Alpha One Gen II sterndrives from 1991 and newer with serial numbers 0D469859 and up. It applies to configurations equipped with an exhaust bellows and corresponds to primary OEM reference 30-803099T1. This is a transom bellows and seal repair kit, not a lower shift cable kit.
Match the application
This transom bellows seal repair kit fits MerCruiser Alpha One Gen II sterndrives from 1991 and newer with serial numbers 0D469859 and up when equipped with an exhaust bellows.
Do not select this kit solely by the MerCruiser brand name or the Alpha One model name. Confirm Generation II, the 1991 and newer year range, serial number 0D469859 and up, and the exhaust-bellows configuration on your stern drive before ordering.
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MerCruiser · Alpha One Gen II
Year: 1991 and newer
Serial number: 0D469859 and up
For stern drives equipped with exhaust bellows.
Applies with the stated conditions
Numbers to compare
Use these reference numbers to identify the kit and compare against your existing service records. Check the complete reference number, including the T1 suffix; similar numbers do not automatically mean all versions or sub-components are directly interchangeable.
Primary OEM kit references
| Mercury Mariner / Quicksilver | 30-803099T1, 30-803099t 1 |
|---|---|
| Mercury Mariner | 30-803099T 1, 30803099T1, 803099T1 |
Aftermarket kit references
| Sierra | 18-8218 (listed as sealed-bearing version), 18-8206-1 (listed with greasable gimbal bearing) |
|---|---|
| SEI Marine | 9A-116 |
| OBR Red Rhino | MR-907 |
| Mallory | 9-72900 |
| GLM | 21960 |
Additional associated and component references
The following numbers are cross-referenced with this record in parts catalogs (including individual component numbers or related assembly variations). Do not treat individual component numbers as a complete kit equivalent.
| Mercury Mariner | 30-803099T, 30-879194A01, 30-879194A02, 30-862540A3, 30-60794A4, 27-94996Q2, 32-8M0109048, 74639, 8M0124227, 816431A1, 26-88416 |
|---|---|
| Sierra | 18-2600, 18-21006 |
| GLM | 21906, 39622, 47240, 89080, 89100, 89180, 85910 |
Technical details
| Product type | Transom Bellows Seal Repair Kit |
|---|---|
| Brand | GH Marine |
| Target drive series | MerCruiser Alpha One Gen II (1991 & newer, S/N 0D469859 & up) |
| Exhaust configuration | For drives equipped with exhaust bellows |
| Primary OEM reference | 30-803099T1 |
Supplied contents
- Transom bellows seal repair kit
This item is a transom bellows and seal repair kit, not a lower shift cable kit. If your repair requires a specific gimbal bearing style (greasable versus sealed) or specific sub-component breakdown, contact GH Marine before ordering to confirm the exact contents for your job.
Workshop sequence
General workshop guidance only; use the service procedure for your exact drive or engine configuration.
- Verify that the stern drive is an Alpha One Gen II unit (1991 and newer, serial number 0D469859 and up) configured with an exhaust bellows, and lay out all service parts against the parts diagram.
- Isolate the battery and propulsion systems according to the MerCruiser service manual, then support and remove the stern drive unit safely.
- Before removing old bellows, hoses, or seals from the gimbal housing and bell housing, record clamp screw orientations, convolution positions, and routing paths.
- Clean all mounting flanges, grooves, and sealing lands thoroughly; inspect the transom assembly, gimbal bearing bore, and water passage ports for corrosion, pitting, or scoring.
- Install the replacement seals and bellows without twisting or pinching the rubber convolutions, applying the adhesives, lubricants, and tooling specified in the service manual for your exact drive serial number.
- Position and tighten all clamps and fasteners according to the service manual so clamp housings do not chafe adjacent hoses or bellows throughout the full steering and trim range.
- Check gimbal bearing alignment, complete drive reinstallation, and verify shift operation and watertight integrity before returning the vessel to service.
Before reassembly
- Confirm that your stern drive serial number is 0D469859 or higher and that it is an Alpha One Gen II model rather than an earlier Alpha One (Gen I) drive.
- Verify that your transom assembly uses a clamped exhaust bellows rather than an exhaust tube, and compare reference number 30-803099T1 with your parts catalog.
- Inspect the lower shift cable and shift cable bellows area while the drive is removed, as a lower shift cable kit is separate from this transom seal repair kit.
- Check the gimbal bearing style and grease passage orientation on the gimbal housing so maintenance expectations match the installed bearing type.
Questions from the workshop
Does this kit fit earlier MerCruiser Alpha One (Gen I) stern drives?
No. This kit is specified for MerCruiser Alpha One Gen II stern drives from 1991 and newer with serial numbers 0D469859 and up. Do not select it based only on the Alpha One name without confirming Generation II and the serial number.
Why are both Sierra 18-8218 and 18-8206-1 listed in the reference numbers?
In aftermarket catalogs, Sierra 18-8206-1 is listed with a greasable gimbal bearing while Sierra 18-8218 is listed as a sealed-bearing version. Both cross-reference to the Alpha One Gen II transom service application, but they should not be used to assume identical bearing maintenance requirements across all kits.
Is a lower shift cable included in this transom repair kit?
This is a transom bellows and seal repair kit corresponding to reference 30-803099T1. If a lower shift cable is needed for your repair, confirm the supplied components before ordering.
What exhaust configuration does this kit match?
It is specified for MerCruiser Alpha One Gen II stern drives equipped with an exhaust bellows. Verify whether your drive uses an exhaust bellows before ordering.
Why does the reference list include numbers like 27-94996Q2 or 816431A1?
Transom service kits cross-reference to several individual OEM and aftermarket sub-component numbers (such as mounting gaskets, bellows, hoses, or bearings). Use 30-803099T1 as the primary kit reference, and do not assume an individual component number represents the entire repair kit.
About GH Marine
GH Marine focuses on bellows and related marine service parts. Compare the application details, reference numbers and supplied contents together to select the part for your repair.
Delivery information
Estimated delivery: 7–15 calendar days.
Planning a repair for a particular date? Contact GH Marine before ordering to discuss delivery to your destination. Check that your delivery address and contact details are complete when placing your order.
For a delivery question about an existing order, have your order number and delivery destination ready when you contact GH Marine.
Warranty and assistance
Contact GH Marine for the warranty terms applicable to this product and assistance with a product issue.
Payment & Security
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