Gear Lube Monitor Reservoir Kit – Fits MerCruiser Alpha One Gen 2, Bravo (Replaces 19742A1, 806193A48)

$64.00

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Gear Lube Monitor Reservoir Kit – Fits MerCruiser Alpha One Gen 2, Bravo (Replaces 19742A1, 806193A48) is backordered and will ship as soon as it is back in stock.

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Product Details

This Gear Lube Monitor Reservoir Kit is an essential component for preventative maintenance on MerCruiser Alpha One Gen 2 (1988–1998) and Bravo stern drives. It actively monitors the gear lube level, alerting you to potential leaks or low fluid conditions before costly damage can occur.

It serves as a direct replacement for Mercury OEM part numbers 19742A1, 19742A3, 19743A3, 19743A4, 806193A20, 806193A38, and 806193A48.

Installs conveniently on the transom or in the engine bay with the included mounting bracket.
Features an integrated float switch and sensor for reliable low-lube-level detection.
Connects to the oil line via a standard hose barb fitting for a secure connection.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number
Mercury	19742A1
Mercury	19742A3
Mercury	19743A3
Mercury	19743A4
Mercury	806193A20
Mercury	806193A38
Mercury	806193A48

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For MerCruiser owners, this kit fits popular Alpha One Gen 2 and Bravo stern drive models. Please check the specific years listed.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
MerCruiser	Alpha One Gen 2	Various	4-Stroke	1988–1998	19742A1, 806193A48
MerCruiser	Bravo	Various	4-Stroke	1991+	19742A1, 806193A48

Technical Specs

Product Type: Gear Lube Monitor Reservoir Kit
Installation: Transom or engine bay mounting (includes bracket)
Connection: Hose barb for oil line
Housing Material: Plastic
Housing Color: Black
Fitting Type: Quick connector
Other Technical Attributes: Includes float switch and sensor

What’s in the Box

1 x Gear Lube Bottle Assembly with Bracket (19742A1)
1 x Strap
1 x Clip
2 x Screws
2 x Washers

Installation Notes

Ensure the engine is off and the battery is disconnected for safety.
Identify a secure mounting location on the transom or a suitable spot within the engine bay that allows for easy access and hose routing.
Use the provided screws and washers to fasten the mounting bracket securely to the chosen surface.
Mount the gear lube reservoir bottle onto the bracket and secure it with the strap and clip.
Connect the hose from the stern drive's gear lube system to the reservoir's hose barb connector, ensuring a tight fit to prevent leaks.
Connect the sensor's electrical leads to the vessel's helm monitoring system or warning buzzer/light.
Fill the reservoir with the manufacturer-recommended gear lube to the designated "Full" line.
Reconnect the battery, turn the ignition to the "On" position (without starting the engine), and test the alarm system per your boat's manual.
Start the engine and re-check all connections for any signs of leakage.

Troubleshooting & FAQ

How do I know if this reservoir kit fits my stern drive?

This kit is designed for MerCruiser Alpha One Gen 2 (1988–1998) and Bravo (1991+) stern drives. The most reliable way to confirm fitment is to match your old part number to one of the direct replacement numbers listed in our Part Number Matrix, such as 19742A1 or 806193A48.

What is the purpose of the float switch and sensor?

The internal float switch detects when the gear lube level drops below a safe minimum. It sends a signal through the sensor to your boat's helm gauge or warning light, alerting you to a potential leak or low-fluid condition before it can cause serious damage to your stern drive gears.

What are common signs that my current gear lube monitor is failing?

Signs of a faulty monitor include a persistent false alarm even when the lube level is full, or no alarm when the fluid is visibly low. You may also notice physical damage like cracks in the plastic bottle, or fluid leaks around the hose connection or sensor seal.

Can I install this myself?

Yes, installation is straightforward for those with basic mechanical skills. It involves mounting the bracket, connecting a single hose, and hooking up the two-wire sensor. However, professional installation is always recommended to ensure it's done correctly and safely.

Is there a difference between the various replacement part numbers?

The multiple part numbers (e.g., 19742A1, 806193A48) often represent minor updates, different kit configurations, or supersessions over the years. This aftermarket kit is designed to consolidate those variations and serve as a functional equivalent for all listed numbers.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

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