GH Marine  |  SKU: 17B3005

Transom Bellows Seal Kit for MerCruiser R / MR — 30-803097T1 | GH Marine

Regular price $81.50


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GH MARINE / BELLOWS & RELATED PARTS

About this part

This transom bellows seal kit is intended for transom bellows and seal servicing on specified MerCruiser R, MR, Alpha 1 and Alpha 1 SS sterndrives. Identify the kit by its complete reference number and component configuration rather than by drive family name alone. Do not treat the exhaust-bellows reference 30-803097T1 and the exhaust-tube reference 30-803098T1 as identical kit configurations.

Match the application

This transom bellows seal kit applies to the MerCruiser R, MR, Alpha 1 and Alpha 1 SS sterndrive applications listed below when the model year and serial number match.

Check the drive model designation, production year range and serial number range together before ordering, and confirm the component configuration and bearing type required for your transom repair.

  • MerCruiser · R

    Year: 1983-90

    Serial number: S/N 6225577-0D469858

    Application match

  • MerCruiser · MR

    Year: 1983-90

    Serial number: S/N 6225577-0D469858

    Application match

  • MerCruiser · Alpha 1

    Year: 1983-90

    Serial number: S/N 6225577-0D469858

    Application match

  • MerCruiser · Alpha 1 SS

    Year: 1986-89

    Serial number: S/N 0A545004 & Up

    Application match

Numbers to compare

Use the reference numbers below to help identify your transom service kit. Similar or nearby reference numbers do not automatically mean every kit version, bearing style or exhaust connection configuration is interchangeable.

OEM reference numbers

Mercury / Mariner / Quicksilver 30-803097t 1
Mercury / Mariner 30-803097T 1
Mercury / Mariner / MerCruiser 30-803097T1
Mercury / Mariner 30803097T1
Mercury / Mariner 803097T1

Aftermarket reference numbers

Sierra Marine 18-8213 (listed as a reference version with a sealed gimbal bearing; does not establish the bearing type supplied with this product)
Sierra Marine 18-2601-1 (listed as a reference version with a greasable gimbal bearing; does not establish the bearing type supplied with this product)
SEI Marine 9A-108
OBR Red Rhino MR-902
Mallory Marine 9-72902
GLM 21950

References with configuration differences or unconfirmed relationship

Mercury / Mariner 30-803098T1 (exhaust-tube reference; do not treat as an identical kit configuration to exhaust-bellows reference 30-803097T1)
Sierra 18-8205 (associated reference record; verify exact component and bearing configuration before treating as equivalent)
Sierra 18-8217 (associated reference record; verify exact component and bearing configuration before treating as equivalent)
GLM 21951 (associated reference record; verify exact kit configuration before treating as equivalent)
Mallory 9-72901 (associated reference record; verify exact kit configuration before treating as equivalent)
Unbranded reference RL8205 (associated reference record; verify exact kit configuration before treating as equivalent)
Identify the kit by its complete reference number and component configuration, not by “Alpha One” alone. Sierra 18-8213 is listed with a sealed gimbal bearing, while Sierra 18-2601-1 is listed with a greasable gimbal bearing; these reference versions do not establish the bearing type supplied with this product.

Technical details

Product type Transom Bellows Seal Kit
Brand GH Marine
Target drive platform MerCruiser R, MR, Alpha 1 and Alpha 1 SS sterndrives (within stated year and serial boundaries)
Service function Transom bellows and seal servicing
Primary OEM reference style Exhaust-bellows kit reference 30-803097T1 (distinct from exhaust-tube kit reference 30-803098T1)

Supplied contents

  • Transom bellows seal kit

Confirm the exact component list and gimbal bearing type required for your repair before purchase.

Workshop sequence

General workshop guidance only; use the service procedure for your exact drive or engine configuration.

  1. Verify the MerCruiser drive model, production year and serial number, and compare all new kit pieces against the components required for your transom assembly before disassembly.
  2. Isolate the battery and propulsion systems according to the service manual, and securely support the sterndrive unit before removing it from the bell housing.
  3. Note the routing, orientation and clamp positions of the existing bellows, hoses and seals on the gimbal housing and bell housing prior to removal.
  4. Remove the worn transom service components and clean all mating grooves, flanges and sealing surfaces thoroughly, checking for corrosion, pitting or housing wear.
  5. Inspect adjacent transom and drive interface components according to the manufacturer service procedure to confirm whether any additional parts or tools are required.
  6. Fit the new bellows and sealing components without twisting or kinking the convolutions, following the service manual for any required adhesives, special tools and clamp orientations.
  7. Complete reassembly and perform the shift, clearance and water-tightness checks specified in the MerCruiser service manual before returning the vessel to service.

Before reassembly

  • Confirm that your drive matches either R / MR / Alpha 1 (1983-90, S/N 6225577-0D469858) or Alpha 1 SS (1986-89, S/N 0A545004 & Up).
  • Verify whether your exhaust passage uses an exhaust bellows (30-803097T1 reference style) rather than an exhaust tube (30-803098T1 reference style).
  • Check the supplied parts on hand against the exact component configuration and gimbal bearing style (sealed versus greasable) required for your transom housing.
  • Inspect the gimbal housing and bell housing sealing necks, shift cable path and water passage connections as directed by the service manual before installing new rubber and seal parts.

Questions from the workshop

Can I order this kit based only on having an “Alpha One” drive?

No. Identify the kit by its complete reference number, component configuration, model year and serial number range. For R, MR and Alpha 1 drives, the listed coverage is 1983-90 with serial numbers 6225577-0D469858; for Alpha 1 SS drives, the listed coverage is 1986-89 with serial numbers 0A545004 & Up.

Are OEM references 30-803097T1 and 30-803098T1 the same kit?

No. Reference 30-803097T1 is an exhaust-bellows kit reference, while 30-803098T1 is an exhaust-tube kit reference. Do not treat them as identical kit configurations.

What is the difference between the Sierra 18-8213 and 18-2601-1 references listed on this page?

In aftermarket catalogs, Sierra 18-8213 is listed with a sealed gimbal bearing, while Sierra 18-2601-1 is listed with a greasable gimbal bearing. Those reference listings do not establish the bearing type supplied with this product, so confirm the bearing type and component list needed for your repair before purchase.

Why are numbers like Sierra 18-8205, 18-8217, GLM 21951, Mallory 9-72901 and RL8205 shown separately?

Those numbers appear in associated cross-reference records, where kit contents, exhaust style or bearing style can differ between brands and versions. Compare your required component configuration carefully rather than assuming every cross-reference has identical contents.

What if my MerCruiser serial number falls outside 6225577-0D469858 or 0A545004 & Up?

If your drive serial number or model year is outside the stated boundaries—such as later Alpha One Gen II units or earlier pre-1983 drives—do not assume compatibility. Check your MerCruiser parts catalog by serial number and compare the OEM reference number before ordering.

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.

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