Mercury – Quicksilver 811635Q2 Distributor Cap Kit | GM 4-Cylinder Engines | Delco EST Ignition | 811635Q2

Overview

Every boater knows that a reliable start sets the tone for the whole day. The Quicksilver 811635Q2 Distributor Cap Kit helps keep that confidence alive. Designed for marinized 4-cylinder GM engines with Delco EST ignition systems, this OEM kit includes both the cap and rotor — the heart of your ignition system.

It’s built to handle the tough stuff: heat, vibration, and moisture. Whether you’re idling out of the slip or running wide open across the bay, this kit keeps your spark clean and steady, so your engine fires up quick and runs strong every time.

Key Features

• Purpose: Restores clean, consistent spark delivery for smooth starts and efficient ignition performance.
• Fitment: For 4-cylinder MerCruiser engines made by General Motors with Delco EST (Electronic Spark Timing) ignition systems.
• Construction: Distributor cap molded from a PBT/PET composite for strength, heat resistance, and shape retention under marine conditions.
• Electrical Components: Solid brass inserts prevent corrosion and pitting, ensuring reliable electrical contact and long service life.
• Design Advantage: Rotor has a high strength-to-weight ratio, built to resist cracking and maintain balance under thermal stress.

Engine & Boat Compatibility

• GM-based 4-cylinder MerCruiser sterndrive engines
• Delco EST ignition systems
• Common on small runabouts, bowriders, and compact inboard cruisers

Performance & Practical Benefits

The 811635Q2 kit gives your ignition system a fresh start. The brass terminals inside the cap maintain a strong, even electrical path, keeping the spark steady from idle to top end. The cap’s composite blend holds its shape when the engine bay heats up, preventing warping that can cause misfires.

The rotor is balanced and durable, keeping timing accurate under constant vibration. Together, they create a reliable spark path that helps your motor start quicker, idle smoother, and respond faster to throttle. If your current ignition setup shows wear, corrosion, or uneven performance, swapping in this OEM kit will make your engine feel sharp again.

Why Buy OEM

Ignition components live in a tough environment — heat, salt air, and constant movement. Mercury’s OEM parts are designed specifically for marine engines, not adapted from automotive parts. The result is better insulation, cleaner conductivity, and longer life.

Aftermarket parts might look similar, but looser tolerances or cheaper plastics can cause misalignment or corrosion over time. When you choose OEM, you get precision-built components tested in real marine conditions, ensuring they’ll perform exactly as your engine’s ignition system was designed to.

FAQ

Q1: What engines fit the Quicksilver 811635Q2?
A: It fits marinized GM 4-cylinder MerCruiser engines with Delco EST ignition systems.

Q2: What’s included in the kit?
A: The kit includes both the distributor cap and rotor.

Q3: Is this safe for saltwater use?
A: Yes. The materials and brass contacts are corrosion-resistant and built for long life in marine environments.

Q4: Will it interfere with electronics?
A: No. The cap is designed to resist RFI interference, keeping GPS, radios, and onboard systems running clearly.

Q5: How often should I replace the cap and rotor?
A: Inspect them every 100 hours or once a season, and replace if you notice corrosion, pitting, or starting issues.