Q & A

Frequently asked questions

Boat Servicing and Engine care

How often should I service my outboard motor?


Every year, or every 100hrs (Which ever comes first)




How often should i service my inboard?


Every 100hrs or once a year (which ever comes first)




Do you do boat servicing in my area?


Our Marine centre is located in at Whitianga 14 Moewai Rd (by the Aerodrome) and we service the whole coromandel peninsular and provide winter mobile servicing to areas such as Coromandel, Whitianga, Hot Water Beach, Hahei, Cooks Beach, Flaxmill Bay, Ferry Landing, Coroglen, Whenuakite, Kuaotunu, Rings Beach, Matarangi and Whangapoua, the Peninsula's east coast, Tairua and Pauanui




How often should gear oil be changed?


Every 100 hours or every year ( which ever comes first)




How often should you change the impeller in an outboard motor?


We always say the Impeller is "heart" of your engine. It's not an overly expensive part and gambling on the integrity of your impeller could ruin your whole weekend or even cause some nasty damage to your engine. At Mercury Bay Marine we throughly inspect your water pump during your yearly service for any wear or damage and often they will be replaced then. But what if I haven't used my boat much this year? Sometimes sitting in the same position for a long period of time can also compromise the integrity of your impeller so it’s still important to inspect it annually or every 100 hours (which ever comes first)




If you come to my boat for servicing, will I need to be there?


We do mobile servicing all through the winter months, you wont need to be there as long as we have acess to a hose and power for our CDS equipment. Over peak season we offer a pick up and delivery service. *Please note all Sealegs servicing is carried out at our workshop only, but we are able to collect your Sealegs (with our trailer or your own) and return it after servicing has been completed.




Do you do Trailer WOF and trailer repairs?


We can organise for your trailer to be warranted while your boat is being serviced with us. Infact just about everything can be done right here in Whitianga through our trusted marine associates we can organise your trailer W.O.F, Upholstery repairs and refits, SignWriting, Fiberglass Repairs and more, meaning you can drop your boat at one shop and we can take care of it all, giving you a stress free service experience and saving you the hassle of having to tow the boat around town or over the hill.




How do i care for my boat?


Before Every Trip Check that you have adequate fuel and that the fuel tank vent is open Make sure the oil tank (if the engine has one) is topped up If the engine is not thru-bolted to the transom, ensure that the engine mount screw clamps are secure and tight Check that the water intake pickup is clean and free from debris Check your prop for fishing line wrapped around the hub area, and check for excess oil buildup near the prop (a small amount is normal, so look for changes in the quantity) indicating a deterioration of the lower unit seal After Every Trip After every outing, flush out the engine which is espcially important after salt water adventures. Buy a set of “ear muffs,” an engine flusher with two flexible rubber seals connected with a metal clamp. Slip the apparatus onto the lower unit where the water is picked up and attach a garden hose. Open the tap no more than about one-quarter of maximum water pressure (full water pressure from a city water system could damage the internal seals in your outboard motor). Start up the engine, run it up to about 2,000rpm (or to your engine manufacturer’s recommended rpm setting) and let the water pump do the rest. Allow the motor to run up to operating temperature, so the thermostat will open and allow water to circulate through the cooling system. (Stay clear of the prop and make sure no one tries to shift the motor into gear. Note: Many experts advise you to remove the prop for safety whenever running your engine out of the water) While you’re flushing the motor, check the water pump to make sure it has good water flow. Carefully put your finger through the stream of water. It may be warm, but it shouldn’t be hot. If the output is not strong, you may have some debris stuck in the outflow tube. Immediately shut down the engine to prevent overheating and damage. Insert a small piece of wire into the flow tube and work it back and forth. Start the engine again and check the output. If that doesn't solve the problem, you may need a new water pump. After flushing the engine, disconnect the fuel line and allow the engine to burn all the fuel in the carburetor. Once you’ve finished the flushing and run the engine out of fuel, turn off the key and the battery switch. This flushing procedure should take a total of about five to ten minutes. Wipe everything down and spray with a corrosion inhibitor.. Lubricate all the moving parts such as the shift and throttle cables, carburetor linkages, etc. Lubricate moving parts, such as the shift and throttle cables and the carburator linkages. Replace the cowling and wipe it down. Keep a canvas or plastic cover on the engine between trips. Regular Maintenance & Servicing To protect your investment and to keep your boat safe, economical and reliable it's important to have yearly servicing with at a certified Marine Centre. There are a few things you can do yourself at home too. Periodically check the fuel line for cracks and worn spots. Make sure the fuel primer bulb is not cracked and is pliable. Check the clamps on the fuel line for rust or corrosion. Check the fuel tank(s) for damage and corrosion. Check the tank vent to make sure it is free of obstructions. Check regularly for water in the fuel (especially important with fuels containing ethanol alcohol). If the engine has a clear fuel strainer, check if any water has collected there. It will be a relatively clear layer at the bottom of the strainer. Clean the exterior with boat soap and apply a good wax job. Inspect the propeller for dents and dings. Invest in a smart charger for your battery to keep the condition of your battery up. Check the condition of your trailer wheel bearings to make sure they aren’t rumbling. If your boat has cable steering insure move engine left to right periodically to prevent steering seizing. Use a fuel stabiliser if you wont be using your boat for more than two months. Use a boat cover and outboard cover in between trips.





Marine parts and chandlery


Marine Electronics

I purchased my fishfinder elsewhere and I need repairs, can Mercury Bay Marine help me with this?


Sure, as long as you have purchased your unit from an authorised New Zealand dealer we will be happy to help. We are agents for Furuno Garmin Lowrance Simrad Raymarine *Please note that if the unit has been purchased from a non authorised NZ dealer we may not be able to get repairs done on your behalf, and warranty may also be void.




Which marine electronic brands and equipment do you supply and fit?


We are authorise installation and repair agents for: Simrad, Lowrance, Garmin, Furuno, Simrad, B&G, Raymarine Fusion Marine and more.. As direct suppliers for all of the best marine electronics brands, we cut out the middle man and pass on the best deals to you. With a great range of GPS, autopilots, radar, fishfinders, navigation software, radio communications and satellite TV and data equipment available, Mercury Bay Marine has the skill and expertise to fulfill your marine electronics, navigational and communication needs Call into our showroom to try the latest technology with our demo models and talk to Mark, who has a wealth of knowledge and experience with the all the leading brands, he will be happy to discuss which options are best suited to your boat and lifestyle. We supply ... GPS DEPTH SOUNDERS / CHART PLOTTERS BATTERY CHARGING SYSTEMS ELECTRIC WINCHES CAMERAS DEPTH SOUNDERS / FISH-FINDERS AERIALS / ANTENNAS EPIRBS AUTOPILOTS RADARS TRANSDUCERS MARINE RADIO COMMUNICATION EQUIPMENT SAFETY EQUIPMENT UNDERWATER LIGHTS LED LIGHTING INVERTERS BATTERIES AND CHARGES STARTER MOTORS & ALTERNATORS LCD TV’S AND ENTERTAINMENT PACKAGES STEREOS/ SOUND SYSTEMS BILGE, FRESHWATER PUMPS ALARM & MONITORING SYSTEMS ELECTROLYSIS PROTECTION SONARS We ship New Zealand wide





Boat Engines

How can I tell if I need a short shaft or long shaft engine for my boat?


If you cant find the information on your existing engine you will need to measure the transom of your boat to find out the length you require. To do so measure from the bottom of the keel to the top of the transom 15" = Short Shaft 20" = Long Shaft 25" = X Long Shaft 30" =XX Long Shaft





Boats for sale

After I have bought a boat what else will I need to purchase?


A coast guard membership, and insurance, two forms of comunication -a V.H.F radio. You will also need safety kit which generally will include: life jackets, flares, anchor, rope, fenders etc.