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Steering stop rings
For Mercury outboard steering cylinders. Limits steering travel so tightly spaced outboards can’t hit each other.
When the engines are closer than the book says
Mercury publishes a minimum engine center-to-center spacing for multi-engine rigs: 26 in. for dual Verado L6. Triple, quad and quint installs often go tighter than that to fit the transom. At full lock, the cowls can then contact the engine next to them.
API stop rings fit the Mercury steering cylinder and shorten its stroke, so the engines stop turning before they touch. Each ring carries an internal Viton O-ring that holds it in place on the cylinder. Rings are sold in pairs, one per side, in one 15 mm size. Need more clearance? Stack more rings on each side to shorten travel further.
| Width | 15 mm (0.59 in.) |
|---|---|
| Outside diameter | 60 mm (2.36 in.) |
| Inside diameter | 45 mm (1.77 in.) |
| Material | Machined aluminum, uncoated. It runs inside the cylinder’s oil, so it needs no finish. |
| Retention | Internal Viton O-ring |
| Sold as | Pair |
| More clearance | Stack rings to shorten travel further |
Machined in-house
Machined from aluminum by American Precision Industries in Hialeah, Florida.
Stays put
An internal Viton O-ring holds the ring in place on the cylinder.
Stack to fit
One size. Add rings to match engine spacing and cowl options. Add-on scoops and air intakes take up extra room.
Proven on quints
Running on 5-engine builds at 23-1/2 in. and 23-5/8 in. center-to-center.
Fitment
How many rings you need per side depends on center-to-center spacing, cowl width and any add-on scoops. Contact us with your engine model and spacing, and we’ll recommend a ring count.
After installation, turn the wheel lock to lock with the engines trimmed down, then again tilted up. Confirm there’s no contact at any point.
Tell us about the rig
- Engine model and horsepower
- Number of engines
- Center-to-center spacing
- Cowl options, scoops or air intakes
Mercury and Verado are trademarks of Brunswick Corporation. American Precision Industries is not affiliated with or endorsed by Mercury Marine.
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