Transom Bellows Kit 86840A05 18654A1 74639A2 for MerCruiser Bravo Blackhawk Drive
Transom Bellows Kit 86840A05 18654A1 74639A2 for MerCruiser Bravo Blackhawk Drive
Product Overview
Transom bellows kit for MerCruiser Bravo and Blackhawk drives, the complete set with the shift cable bellows, the exhaust bellows, the U-joint bellows, four stainless clamps and an outdrive gasket set. It covers 86840A05, 18654A1 and 74639A2, and the whole kit ships in a 15 x 16 x 15 cm box.
It fits Bravo drives from 1982 onward and the Blackhawk drives. Those are the drives where water in the boat is almost always a bellows problem: the two bellows and the shift cable boot are the only thing between the lake and the inside of the transom.
The three bellows do three different jobs. The U-joint bellows keeps water out of the gimbal bearing and the drive shaft, the exhaust bellows carries the exhaust through the transom, and the shift cable bellows seals around the cable. All three harden with age, and one split boot fills the bilge in minutes.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Transom bellows kit, stern drive |
| Fits | MerCruiser Bravo 1982 and up, Blackhawk |
| Contents | Shift cable, exhaust and U-joint bellows, 4 clamps, gasket set |
| Clamp Sizes | 21-44 mm, 52-76 mm, 105-127 mm |
| Net Weight | 1050 g including packaging |
| Pack Size | 150 mm x 160 mm x 150 mm |
| Quantity | 1 complete bellows kit |
OEM Cross Reference
| Component | OEM Part Numbers |
|---|---|
| Shift cable bellows | 74639A2, 74639, 31659 |
| Exhaust bellows | 18654A1, 32734, 32734A3, 8M0124227 |
| U-joint bellows | 60932A1, 60932A4 |
| Kit number, MerCruiser | 86840A05 |
| Gasket set, MerCruiser | 16755Q1 |
| Sierra, shift cable | 18-2753-2 |
| Sierra, exhaust | 18-2750, 18-2751 |
| Sierra, U-joint | 18-2615 |
Compatible Engines & Drives
| Drive | Years | Note |
|---|---|---|
| MerCruiser Bravo One | 1982 and up | Same transom opening |
| MerCruiser Bravo Two | 1982 and up | Same bellows set |
| MerCruiser Bravo Three | 1982 and up | Same bellows set |
| MerCruiser Bravo X, XR, XZ | Later models | Same bellows set |
| MerCruiser Blackhawk | As listed | Same bellows set |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Shift cable bellows | 74639A2 pattern | 1 |
| Exhaust bellows | 18654A1 pattern | 1 |
| U-joint bellows | 60932A1 pattern | 1 |
| Stainless clamps | 21-44 mm, 52-76 mm and 105-127 mm | 4 |
| Outdrive gasket set | For the drive and transom faces | 1 |
Bellows or Something Else
| What You See | What It Means | What To Do |
|---|---|---|
| Water in the bilge after a run | Split bellows or clamp | Pull the drive and inspect before the next trip |
| Grease washed out of the gimbal bearing | U-joint bellows leaking | Kit with a new U-joint bellows |
| Exhaust noise in the boat | Exhaust bellows split | Kit with the exhaust bellows |
| Shift feels stiff and the cable is wet | Shift cable bellows perished | Kit and check the cable |
| Rust on the universal joints | Long term water ingress | Kit plus new U-joints if pitted |
| Bilge pump runs every hour | A bellows is holed | Do not run the boat until it is fixed |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the drive model, Bravo and Alpha bellows are not the same |
| 2 | Pull the drive and drain the gear oil for inspection |
| 3 | Cut the old clamps and pull the bellows out of both the gimbal and the transom |
| 4 | Clean both bellows seats back to bare metal and check for corrosion |
| 5 | Fit the new bellows with the drain hole at the bottom |
| 6 | Fit the new stainless clamps, tighten evenly and do not overtighten |
| 7 | Check the shift cable boot sits square around the cable |
| 8 | Refit the drive with the new gasket set and check for water after the first run |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Fits MerCruiser Bravo drives from 1982 and up, and Blackhawk drives
- The kit replaces 86840A05, 18654A1, 74639A2 and the gasket set 16755Q1
- Contents: shift cable, exhaust and U-joint bellows, four clamps, one gasket set
- Bravo and Alpha One bellows kits are different, check your drive model
- Water in the bilge means a bellows problem, do not wait for the next season
- Clean the bellows seats and fit the drain hole at the bottom
- 30-Day Easy Returns
- Ships from our warehouse with tracking
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Boat Owners' Review
Before You Buy
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