30-803097T1 Transom Repair Bellows Kit Fits MerCruiser Alpha One Gen I R-MR 1983-1990, Replaces Sierra 18-2601-1

30-803097T1 Transom Repair Bellows Kit — Fits MerCruiser Alpha One Gen I R-MR 1983-1990, Replaces Sierra 18-2601-1

This is the full transom service kit for MerCruiser R/MR/Alpha One Gen I sterndrives (1983–1990, serial 6225577–0D469858). It bundles the three Gen I bellows, a gimbal bearing, housing gasket kit, water intake hoses, O-rings, and clamps so you complete the entire transom seal job in one pass while the drive is off. If you already have a solid bearing and only need the rubber, see our rubber-only kit 17B3001.

What is in the box?

Three bellows + gimbal bearing + gasket kit + hardware for a complete Gen I transom service. Each bellow component also available individually on GHMarine.com.

Component	OEM Part No.	GH SKU (single)	Qty
U-joint bellow (ridged)	60932A4	17B1004	1
Exhaust tube	78458A1	17B1015	1
Shift cable bellow	74639A2	17B1005	1
Gimbal bearing	30-60794A4	18MB001	1
Bell housing gasket kit	27-94996T2	20GK002	1 set
O-ring set + water hoses + clamps	25-25439 / 32-32461 / 54-38863	—	as packed

 

Which kit is this?

30-803097T1 is the OEM kit number for Alpha One Gen I drives. The Gen I U-joint bellow (60932A4) has a ridge — Gen II uses a flat bellow 816431A1, Bravo uses 86840A05. If your drive serial is 0D469859 or higher you need Gen II kit 18BK003, not this one.

Signs your transom needs service

·       Water in the bilge after launch — any of the three transom bellows may be torn or de-bonded.

·       Gimbal bearing howl or grinding when turning the wheel — bearing may be rusted or worn.

·       Hard shifting — shift cable bellow may have pulled off its nipple.

·       Visible cracks, dry rot, or soft rubber on any bellow — replace all three while the drive is off.

·       Milky gear oil — water is getting past the drive shaft seals into the gearcase.

·       Spring inspection or scheduled transom service — drive already off, do it all at once.

Will it fit my drive?

Gen I R/MR/Alpha One 1983–1990. Serial 6225577–0D469858.

Brand	Model / Drive	Rated HP	Stroke	Years	OEM Part No.
MerCruiser	R / MR / Alpha One Gen I	120–300	4-Stroke	1983–1990	30-803097T1
MerCruiser	Alpha One SS	120–300	4-Stroke	1986–1989	30-803097T1
MerCruiser	454 / Magnum / JackShaft (Tube)	330–365	4-Stroke	1983–1990	30-803098T1

 

OEM & swap numbers

30-803097T1 / Sierra 18-2601-1 / GLM 21950 / Mallory 9-72902 / PROmarine 68397.

Type	Brand	Part Number	Notes
OEM	Mercury / Quicksilver	30-803097T1	Primary OEM — full transom bellows kit
OEM	Mercury / Quicksilver	30-803098T1	Tube version — 454/Magnum/JackShaft
Aftermarket	Sierra	18-2601-1	Transom Seal Kit — 1:1 replacement
Aftermarket	Sierra	18-8213	Alternate Sierra packaging
Aftermarket	GLM	21950	Transom Service Kit
Aftermarket	Mallory	9-72902	Transom Seal Kit (w/ exhaust bellows)
Aftermarket	PROmarine	68397	Transom Service Kit R/MR/Alpha I

 

Wrong kit? Read before you order

·       NOT NOT for Gen II kit 30-803099T1 — U-joint is 816431A1 (no ridge), see 18BK003

·       NOT NOT for Bravo kit 30-803100T1 — U-joint is 86840A05, see 18B5001

·       NOT NOT a single bellow — this is the full kit with bearing, gaskets, and hoses

·       NOT NOT 17B3001 — that is the rubber-only version (same OEM 30-803097T1, lighter box)

What ships in the box

·       1 × U-Joint Bellows 60932A4 (ridged, Gen I type) with clamp

·       1 × Exhaust Tube 78458A1 with clamps

·       1 × Shift Cable Bellow 74639A2 with clamps

·       1 × Gimbal Bearing 30-60794A4

·       1 × Bell Housing Gasket Kit 27-94996T2

·       2 × Water Intake Hoses (5/8" + 3/4")

·       O-Rings & spare clamps as packed

·       Bellows adhesive — sold separately

·       Bellows expander tool 22ET001 — sold separately

·       U-Joint sleeve driver 21B1001 — sold separately

Install tips while the drive is off

Work in a ventilated area. If unsure, use a marine shop. Drive removal = heavy, use a stand.

1. Remove sterndrive per shop manual. Drain gear oil. Mark shifter position.

2. Scrape off old adhesive from all flanges — any crud left = future leak.

3. Apply bellows adhesive inside both ends of each bellow. Let tack up 10–20 min.

4. Install shift cable bellow first (trickiest access), then U-joint, then exhaust tube last.

5. Use expander tool 22ET001 when seating the exhaust tube end onto the bell housing.

6. Press U-joint aluminum retainer sleeve with 21B1001 — do NOT hammer it.

7. Replace gimbal bearing using a bearing driver. Do not nick the housing bore.

8. Torque all fasteners to spec. Run on muffs in neutral, check bilge.

9. If exhaust tube end doesn't seat, check you are NOT trying a Gen II exhaust bellow (18654A1).

FAQs — the bros want to know

Will this fit my MerCruiser sterndrive?

Yes — for Gen I R/MR/Alpha One drives 1983–1990, serial 6225577 thru 0D469858. This is the FULL transom service kit: 3 bellows + gimbal bearing + gasket set + hoses + O-rings + clamps. NOT for Gen II (1991+) — those use different U-joint bellows 816431A1. Confirm your drive serial on the decal before ordering.

What is in the box?

Three bellows: U-joint 60932A4 (ridged Gen I type), exhaust tube 78458A1, shift cable bellow 74639A2. Plus: gimbal bearing 30-60794A4, bell housing gasket kit 27-94996T2, two water intake hoses, O-rings, and clamps. Bellows adhesive and expander tool sold separately.

How is this different from the rubber-only kit (17B3001)?

17B3001 = same three Gen I bellows only. 17B3005 = bellows + gimbal bearing + gasket kit + hoses + O-rings + clamps. If your bearing is still solid and you only need rubber, save money with 17B3001. If you're pulling the drive for a full transom service, 17B3005 has everything.

Do I need Gen II or Bravo kit instead?

Gen II 1991+ → 18BK003. Bravo 1988+ → 18B5001 or 17B3003 (rubber only). These are NOT interchangeable — the U-joint bellow is different on every generation.

What tools do I need?

Marine bellows adhesive (buy separately), bellows expander 22ET001, U-joint sleeve driver 21B1001 for Gen I aluminum retainer. Gimbal bearing driver and alignment tool recommended. Shop manual strongly advised.

Please note

Aftermarket replacement kit. Not affiliated with Mercury Marine or Quicksilver. "Compatible with", "Replaces", and cross-ref numbers mean this kit is built to work like the originals listed — always confirm fit with your drive serial number (6225577–0D469858 = Gen I). Referenced OEM numbers are for fitment identification only.