Garmin GT51M-THP, GT51M-TM, GT50M-THP, GT50M-TM, GT41-TM Installation Instructions

Transom-Mount Transducer

Installation Instructions

To obtain the best performance and to avoid damage to your boat, you must install the Garmin® transducer according to these instructions.

Read all installation instructions before proceeding with the installation. If you experience difficulty during the installation, contact Garmin Product Support.

Registering Your Device

Help us better support you by completing our online registration today.

•Go to http://my.garmin.com.

•Keep the original sales receipt, or a photocopy, in a safe place.

Contacting Garmin Product Support

•Go to www.garmin.com/support for in-country support information.

•In the USA, call 913-397-8200 or 1-800-800-1020.

•In the UK, call 0808 238 0000.

•In Europe, call [phone].

Important Safety Information

WARNING

See the Important Safety and Product Information guide in the product box for product warnings and other important information.

You are responsible for the safe and prudent operation of your vessel. Sonar is a tool that enhances your awareness of the water beneath your boat. It does not relieve you of the responsibility of observing the water around your boat as you navigate.

CAUTION

Failure to install and maintain this equipment in accordance with these instructions could result in damage or injury.

Always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding.

NOTICE

When drilling or cutting, always check what is on the opposite side of the surface.

This equipment should be installed by a qualified marine installer.

Loading the New Software on a Memory Card

You must copy the software update to a memory card using a computer that is running Windows® software.

NOTE: You can contact Garmin customer support to order a preloaded software update card if you do not have a computer with Windows software.

1 Insert a memory card into the card slot on the computer. 2 Go to www.garmin.com/support/software/marine.html.

3Select Download next to the software bundle that corresponds with your device.

4 Read and agree to the terms.

5 Select Download.

6 If necessary, select Run.

7If necessary, select the drive associated with the memory card, and select Next > Finish.

Updating the Device Software

Before you can update the software, you must obtain a software-update memory card or load the latest software onto a memory card.

1 Turn on the chartplotter.

2After the home screen appears, insert the memory card into the card slot.

NOTE: In order for the software update instructions to appear, the device must be fully booted before the card is inserted.

3 Follow the on-screen instructions.

4Wait several minutes while the software update process completes.

The device returns to normal operation after the software update process is complete.

5Remove the memory card.

NOTE: If the memory card is removed before the device restarts fully, the software update is not complete.

Tools Needed

•Drill and drill bits

•Two 13 mm hex wrenches

•Number 2 Phillips screwdriver

•Masking tape

•Marine sealant

About the Transducer

The transducer transmits and receives sound waves through the water, and relays sound-wave information to your Garmin sonar device.

Assembling the Transducer with a Transom Mount Bracket

1 Attach the mount to the transducer with the included

ÀÁ

8 mm M4 screws , and 4 mm star washers .

 Ã

2 Attach the mount to the bracket with the 16 mm M8 bolts

Ä

, M8 flat washers , and M8 lock nuts .

Å Æ Ç

October 2015

Printed in Taiwan

190-01850-02_0A

Installing the Transducer on a Transom

Mounting Location Considerations

•The transducer should be mounted as close to the center of the boat as possible.

•The transducer should not be mounted behind strakes, struts, fittings, water intake or discharge ports, or anything that creates air bubbles or causes the water to become turbulent.

The transducer must be in clean (non-turbulent) water for optimal performance.

•The transducer should not be mounted in a location where it might be jarred when launching, hauling, or storing.

•On single-drive boats, the transducer must not be mounted in the path of the propeller.

The transducer can cause cavitation that can degrade the performance of the boat and damage the propeller.

•On twin-drive boats, the transducer should be mounted between the drives, if possible.

Installing the Transom-Mount Hardware

NOTICE

If you are mounting the bracket on fiberglass with screws, it is recommended to use a countersink bit to drill a clearance counterbore through only the top gel-coat layer. This will help to avoid any cracking in the gel-coat layer when the screws are tightened.

The cables connected to the transducer should not be cut, because cutting the transducer cables voids your warranty.

1 Position the transducer mount so the center of the bottom

À

of the transducer is level with the bottom edge of the transom and is parallel to the water line.

2 Align the transducer parallel to the water line , and mark the

Á

center location of the two outer holes and the center hole of the transducer mount.

3Wrap a piece of tape around a 4 mm (5/32 in.) bit at 15 mm (19/32 in.) from the point of the bit, to avoid drilling the pilot holes too deep.

4If you are installing the bracket on fiberglass, place a piece of tape over the pilot-hole location to reduce cracking of the gel coat.

5Using the 4 mm (5/32 in.) bit, drill the pilot holes approximately 15 mm (19/32 in.) deep at the marked locations.

6Apply marine sealant to the included 20 mm screws, and attach the transducer assembly to the transom.

NOTE: The third screw in the lower center screw hole stabilizes the mount.

7	If you must route the cable through the transom, choose a
	pilot-hole location well above the waterline à and mark it.
8	Place a cable clamp on the transducer cable Ä,
	approximately one third of the distance between the

transducer and the top of the transom or the pilot hole.

9 Mark the pilot-hole location for the cable clamp, and using a 3.2 mm (1/8 in.) bit, drill a pilot hole approximately 10 mm (3/8 in.) deep.

10Apply marine sealant to the included 12 mm screw, and attach the cable clamp to the transom.

11Repeat steps 8 through 10 to install the other cable clamp approximately two thirds of the distance between the transducer and the top of the transom or the pilot hole.

12If you marked a pilot hole in step 9, choose the appropriate drill bit and drill a pass-through hole completely through the transom:

•If you have the 4-pin cable, use a 16 mm (5/8 in.) drill bit.

•If you have the 8-pin cable or the 12-pin cable, use a 25 mm (1 in.) drill bit.

13Route the transducer cable to the sounder:

•If you are routing the cable using a pass-through hole, feed it through the hole you drilled in step 12, and install

the cable-entry cover (Installing the Cable-Entry Cover,

Ã

page 2).

• If you are not routing the cable using a pass-through hole, route the cable up and over the top of the transom .

Å

Avoid routing the cable close to electrical wires or other sources of electrical interference.

Installing the Cable-Entry Cover

If you routed the cable through the transom after you installed the transducer, you should install the cable-entry cover to keep water from entering your boat.

1 Place the cable-entry cover over the hole and the cable,

À

with the opening pointing downward, and mark the location of the two pilot holes.

2Remove the cable-entry cover, and, using a 3.2 mm (1/8 in.) bit, drill the pilot holes approximately 10 mm (3/8 in.) deep.

2	Transom-Mount Transducer Installation Instructions