Boating - Recent Questions, Troubleshooting & Support

You don't say what kind of speed box you have, but you probably have a "cupped wheel" speed sensor. These need to spin freely with the motion of the water to send a speed signal to your "speed box", but they are easily fouled by corrosion, marine organisms, sea grass or any other sort of debris. Check the sensor for fouling and clean as necessary. Other than that, you may have an electrical problem which is difficult to isolate without test instruments.

Boating | Answered Yesterday

You'll need something close to 12.6v at the plotter to get it to start. Check the battery voltage at the battery terminals. If you've flatted a lead acid battery, it will not be much good for anything after that, even with recharging. If you have 12+ volts at the battery, remove the power connector from the plotter and check the voltage between the hot and ground pins to make sure you are getting power to the plotter. If the battery has any voltage, but the plotter does not, check for continuity of the fuse and/or breaker. Proceed accordingly. You'll likely need a new battery in any case. Hope that helps.

Boating | Answered Yesterday

Hello, Dianne -

Boats have been required to have Hull Identification Numbers (HIN) since 1 Nov 1972 in the USA.

Go to this web page to learn where the HIN should be found on your Grumman boat, if it was made on or after 1 Nov 1972:

Once you find the HIN, the information on the web page should help you determine when your boat was made.

Best wishes.

Boating | Answered Yesterday

The hot wire (positive) is red and the ground (negative) is black or, sometimes, brown. There is also a drain wire in the harness, that should be connected to the RF ground of the boat or, if none, to the negative terminal. You'll also need to add a 3A slow-blow fuse in the positive wire.
Follow the installation instructions as follows:
1. Connect the transducer / power connector to the rear of the unit and secure using the locking collar.
2. The drain wire should be connected to the vessel RF ground point. If your vessel has no groundpoint connect to the negative side of the vessel's power supply.
3. The Negative wire must be connected to the negative side of the 12 V dc power supply.
4. A fuse holder (not supplied) MUST be fitted to the positive wire using a suitably rated inline fuse or breaker.
5. The positive wire must be connected to the positive side of the 12 V dc power supply.

Raymarine... | Answered Yesterday

The 40 signifies the same power output, pick the one that's best for your individual needs regardless of the title as both have the same amount of power!

Let me know if this is helpful by clicking "Helpful", feel free to leave very brief review or follow me, I deal with automotive/mechanical/technical and other subjects relevant to daily life. Thanks and have a great day!

Minn Kota... | Answered 2 days ago

Request the wiring diagram directly from Travis.

Boating | Answered 3 days ago

Dmm Benjamin Air... | Answered on Jan 12, 2019

This page has a diagram and general information. Not all models have a filter.

Owners manuals are here, you need model number

Boating | Answered on Jan 11, 2019

Sounds like a connection problem. Spray the plugs with switch cleaner and them use a little dialectric grease.

Also make sure you have a full 13.5 volts at it. There are also recommendations for wire gauge size and how to connect to the battery.

Boating | Answered on Jan 11, 2019

Ahhh Mercury electrical... always a problem. The charging system on a mercury is really simple. You should have 2 yellow wires coming from the under the flywheel and possibly a black one running with them. These are high voltage a/c. They run to the rectifier/regulator which converts the a/c to d/c and sets the voltage to around 14 volts. To test the charging circuit, disconnect the yellow wires from the rectifier/regulator, *CAUTION HIGH VOLTAGE!* hook up a meter, set to read a/c volts to the two yellow wires and crank the engine, be careful not to touch the wire ends while doing this, it could be a shocking experience. You are just looking for any voltage above 12 volt a/c. If you start the engine during this test you could see upward of 100 volts. If this test fails replace the charging coil under the flywheel, it the one with the yellow wires that you just tested. Chances are this test passed with flying colors.So plug it back in and test the rectifier/regulator. Disconnect the red wire(s) and set your meter to read > 12 d/c volts, there may be 2 red wires. Start the engine and test from the red wire(s) to engine ground, you should see >12vdc. 99.9% of the time this test fails. So replace the rectifier/regulator. It is the weakest link. They will fail for something as simple as a loose or corroded battery terminal.

Mercury Mark 30... | Answered on Jan 10, 2019

When checking the compression on an outboard motor... you aren't looking for the final number as much as the percentages of variation. There are so many things that can vary the compression numbers, like throttle position, air temperature, and even the tilt of the motor on a four stroke, that the manufacturers don't put the numbers out. What you are looking for is less than 10% variation between all cylinders. So if 3 cylinders are giving you 120 psi and the forth cylinder is giving you 105 psi, that hole has a problem. In the old 2 stroke days what we would find is people were using air cooled 2 stoke oil, which has a much higher burn temperature, and fouling the piston rings with tar.

Mercury Boating | Answered on Jan 10, 2019

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