Airmar ST600 - User Manual

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17-038-01 rev. 04 04/12/11

Thru-Hull, Retractable with Valve

Speed & Temperature Sensor

Model ST600

Applications

• Plastic housing recommended for fiberglass or metal hull only.

Never install a plastic housing in a wood hull since swelling of

the wood may fracture the plastic.

• Bronze housing recommended for wood or fiberglass hull only.

Never install a bronze housing in a metal hull because electrolytic

corrosion will occur.

Pretest

Connect the sensor to the instrument and spin the paddlewheel. Check for a

speed reading and the approximate air temperature (in appropriate). If there

is no reading(s) or it is inaccurate, check the connections and try again. If

there is still a problem, return the product to the place of purchase.

Tools & Materials

Safety goggles

Dust mask

Water-based anti-fouling paint (mandatory in salt water)

Electric drill with 10mm (3/8") or larger chuck capacity

Drill bit: 3mm or 1/8"

Hole saw: 51mm or 2"

Sandpaper

Mild household detergent or weak solvent (alcohol)

File (installation in a metal hull)

Marine sealant (suitable for below waterline)

Additional washer [for aluminum hull less than 6mm (1/4") thick]

Slip-joint pliers (installing a metal housing)

Grommet(s) (some installations)

Cable ties

Installation in a cored fiberglass hull (see page 3)

Hole saw for hull interior: 60mm or 2-3/8"

Fiberglass cloth and resin

or Cylinder, wax, tape, and casting epoxy

Mounting Location

CAUTION: Do not mount the sensor near water intake or

discharge openings; behind strakes, fittings, or hull irregularities

that will disturb the flow.

CAUTION: Never mount the sensor directly ahead of a depth

transducer, since turbulence generated by the paddlewheel’s

rotation will adversely affect the depth transducer’s performance,

especially at high speeds. Mount side by side.

CAUTION: Do not mount in line with trailer rollers or bunks that

may damage the transducer’s face.

Turbulence-free water must flow under the paddlewheel at all

speeds. Choose an accessible spot inside the vessel. Allow a

minimum of 200mm (8") of headroom for the height of the

housing, tightening the nuts, and removing the insert.

• Displacement hull powerboats—Locate amidships near the

centerline.

• Planing hull powerboats—Mount well aft to ensure that it is in

contact with the water at high speeds.

• Fin keel sailboats—Mount on or near the centerline and

forward of the fin keel 300–600mm (1–2').

• Full keel sailboats—Locate amidships and away from the keel

at the point of minimum deadrise.

INSTALLATION INSTRUCTIONSOWNER’S GUIDE &

Follow the precautions below for optimal product

performance and to reduce the risk of property

damage, personal injury, and/or death.

WARNING: Always wear safety goggles and a dust

mask when installing.

WARNING: The valve is not a watertight seal! Always

use the insert or blanking plug secured with the safety

wire for a watertight seal.

WARNING: The o-rings must be intact and well

lubricated to make a watertight seal.

WARNING: Always attach the safety wire to prevent the

insert or blanking plug from backing out in the unlikely

event that the cap nut fails or is screwed on incorrectly.

WARNING: Immediately check for leaks when the boat

is placed in the water. Do not leave the boat unchecked

for more than three hours. Even a small leak may allow

considerable water to accumulate.

CAUTION: Never use a fairing with a plastic housing;

the protruding sensor would be vulnerable to damage

from impact.

CAUTION: Never install a metal housing on a vessel

with a positive ground system.

CAUTION: Never pull, carry, or hold the sensor by its

cable; this may sever internal connections.

CAUTION: The arrow on the top of the insert must

point forward toward the bow.

CAUTION: Never use solvents. Cleaners, fuel,

sealants, paint, and other products may contain

strong solvents, such as acetone, which attack many

plastics, greatly reducing their strength.

IMPORTANT: Please read the instructions

completely before proceeding with the installation.

These instructions supersede any other instructions

in your instrument manual if they differ.

Record the information found on the cable tag for future reference.

Part No._________________Date___________

Need help?

Do you have a question about the Airmar ST600 and is the answer not in the manual?

This document describes the Airmar ST600 Thru-Hull, Retractable with Valve Speed & Temperature Sensor, an instrument designed to provide speed and temperature readings for marine vessels.

Function Description:

The ST600 sensor measures boat speed through water and water temperature. It features a retractable design with a self-closing valve that minimizes water flow into the boat when the paddlewheel insert is removed for cleaning or maintenance. The paddlewheel rotates to provide speed data, while a temperature sensor integrated into the unit measures water temperature. The device is designed for thru-hull installation, meaning it passes through the boat's hull, with the paddlewheel exposed to the water flow.

Important Technical Specifications:

Housing Materials: Available in plastic (recommended for fiberglass or metal hulls only) and bronze (recommended for wood or fiberglass hulls only). Plastic housings should never be installed in wood hulls due to potential fracturing from wood swelling. Bronze housings should never be installed in metal hulls due to electrolytic corrosion.
Hole Saw Sizes for Installation:
- Outer skin: 51mm or 2"
- Cored fiberglass hull interior: 60mm or 2-3/8"
Drill Bit Size: 3mm or 1/8" for pilot hole.
Minimum Headroom Required for Installation/Removal: 200mm (8") for housing height, tightening nuts, and insert removal.
Paddlewheel Bearing Life: Up to 5 years on low-speed boats (less than 10 knots/11 MPH) and 1 year on high-speed vessels.
Watertight Seal: Achieved by the insert or blanking plug secured with safety wire and intact, well-lubricated o-rings. The valve itself is not a watertight seal.

Usage Features:

Retractable Design: Allows for easy removal of the paddlewheel insert for cleaning or replacement without hauling the boat. The self-closing valve minimizes water ingress during this process.
Valve Operation: The curved flap valve is activated by both a spring and water pressure, pushing it upward to block the opening when the insert is removed.
Mounting Location Considerations:
- Displacement hull powerboats: Amidships near the centerline.
- Planing hull powerboats: Well aft to ensure water contact at high speeds.
- Fin keel sailboats: On or near the centerline, 300-600mm (1-2') forward of the fin keel.
- Full keel sailboats: Amidships, away from the keel at the point of minimum deadrise.
- Avoidance Areas: Near water intake/discharge, behind strakes/fittings/hull irregularities, directly ahead of a depth transducer (due to turbulence affecting depth transducer performance), or in line with trailer rollers/bunks.
Orientation: The arrow on the top of the insert and the flange of the housing must point forward toward the bow.
Safety Wire: Mandatory to prevent the insert or blanking plug from backing out.
Pretest: Connect the sensor to the instrument and spin the paddlewheel to check for speed and approximate air temperature readings before installation.

Maintenance Features:

Anti-fouling Paint Application: Mandatory in salt water. Use only water-based anti-fouling paint. Apply to the outside wall of the paddlewheel insert below the lowest o-ring, paddlewheel cavity, paddlewheel, bore of housing up 30mm (1-1/4"), exterior flange of housing, and blanking plug below the lowest o-ring. Reapply every 6 months or at the beginning of each boating season.
Cleaning the Paddlewheel: Regularly clean aquatic growth from the paddlewheel's surface using a Scotch-Brite® scour pad and mild household detergent. For severe fouling, the paddlewheel shaft can be pushed out for thorough cleaning.
O-ring Inspection and Lubrication: O-rings on the paddlewheel insert and blanking plug must be inspected for abrasions/cuts and lubricated with silicone lubricant or petroleum jelly (Vaseline®) to ensure a watertight seal. Replace damaged o-rings.
Blanking Plug Use: Recommended for protecting the paddlewheel when the boat is kept in salt water for more than a week, removed from the water, or if aquatic growth is suspected.
Winterizing: Remove the blanking plug after hauling the boat for winter storage to allow water to drain, preventing freezing and potential cracking.
Replacement Parts: Paddlewheel & Valve Kit (33-250), Blanking Plug Kit (20-600), Cap Nut (plastic 04-234-1, bronze 02-131-01), Hull Nut (plastic 04-004, bronze 02-030), and Housing & Hull Nut Kit (plastic 33-340-02, bronze 33-340-01) are available. Information for ordering is found on the cable tag.
Servicing the Valve Assembly: If the valve fails, it can be serviced by removing the snap ring, disassembling the flap valve, and cleaning/repairing components.
Leak Checks: Immediately check for leaks after the boat is placed in water. Do not leave the boat unchecked for more than 3 hours. Repeat "Bedding" and "Installing" if a leak is observed.

Airmar ST600 Specifications

General

Brand	Airmar
Model	ST600
Category	Measuring Instruments
Language	English