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Help and Frequently Asked QuestionsProduct Questions (click to reveal answer):
- Shaft Length:How do I measure?
If using an auxiliary mounting bracket: With the bracket in the down position, measure from the top of the bracket's mounting surface down to the bottom of the hull or keel (lowest point where engine will be mounted). Tip: For most auxiliary applications, it is possible to use a longer shaft length than what is called for, provided there is sufficient clearance when the engine is in the up position. This can be especially useful in heavy seas.
If measuring an existing outboard: Measure from the inside top of mounting bracket down to anti-cavitation plate above propeller (this is the largest plate/fin directly above the propeller). See diagram below.
|Height Measurement:||Recommended Shaft Length:|
|14” – 17.25”||15” Shaft (Short)|
|17.25” – 19.5”||Varies by application – email us|
|19.5” – 22.5”||20” Shaft (Long)|
|22.5” – 27”||25” Shaft (Extra-Long)|
- Engine Oil: Do 4-stroke outboards come with engine oil pre-filled?
- Oil Type:What type of oil should I use in my 4-stroke outboard?
|2.5hp and 3.5hp||10 fl oz. (300 mL)|
|4hp, 5hp and 6hp||15 fl oz. (450 mL)|
|8hp and 9.8hp||27 fl oz. (800 mL)|
|15hp and 20hp||1 qt. (1000 mL)|
|25hp and 30hp||2 qt. (1800 mL)|
NOTE: With four-stroke outboards, oil is added directly to the engine crankcase. Four-stroke outboards use straight gasoline in the fuel tank (no oil mix). Mercury recommends that engine oil be changed every 100 hours or once yearly, whichever occurs first. See your owner's manual for detailed information on how to fill and change engine oil.
- Transport/Storage:Can a 4-stroke outboard be laid on its side?
- Lower Unit Oil :Do outboards come with lower unit oil pre-filled?
- Fuel Type: What type of gasoline should I use in my outboard?
Fuels containing up to 10% ethanol are acceptable for use in all Mercury outboards. Use of a fuel stabilizer is highly recommended to help maintain fuel. Fuel stabilizers include oxidation inhibitors and water absorbing agents which help prevent corrosion, fuel degradation and gum formation in your engine's fuel system.
- Fuel Consumption: How much fuel is used per hour at full throttle?
Please Note: Many factors affect fuel consumption and therefore figures listed below are approximate only will not necessarily be what you will obtain. Factors such as weight, hull shape, hull condition, water conditions, etc. can drastically affect the amount of actual fuel consumption. .
The following charts show the approximate fuel consumption of each portable model:
|Approximate Fuel Consumption Chart
Mercury Outboards (current models)
- Electric Start Models: Do they have back-up manual start also?
- What is the smallest outboard that offers electric start?
Smallest Short Shaft Outboard with Electric Start: 9.8hp
The 8hp is the smallest Mercury outboard offered with an electric start option.
All portable outboards with electric start also include a 12V charging system pre-installed and full through-cowling back-up manual rope start (just as found on manual start models) as standard equipment.
- 12V Alternator:How much is a 12V Alternator kit for my outboard?
What does it do?
The 12V charging system allows the user to charge a 12V battery. With this option installed, the outboard engine will send charging current to the battery when the outboard engine is running. The output is variable based on engine RPM.
Who needs this option?
Anyone who has a 12V battery in their boat (for lighting or other accessories) and would like an alternative or supplemental charging method.
NOTE: The 12V Alternator/Charging System is an option only and is NOT required to operate the outboard. This feature can be added to manual start models from 4hp - 20hp. On 8hp - 20hp electric start models, this feature is standard equipment and no additional purchase is necessary. This feature is also standard on 6hp Sail Pro models.
How much is a 12V Alternator/Charging kit for my outboard?
We offer genuine Mercury 12V charging systems that include a rectifier which provide your outboard with the ability to charge a 12V battery should you have the need or desire to do so.
MANUAL START MODEL OUTBOARDS Optional 12V Charging System Cost:
4, 5, 6hp* = $229.99 w/Free Shipping
8, 9.8hp = $229.99 w/Free Shipping
15, 20hp = $189.99 w/Free Shipping
For manual start models, the add-on 12V charging system requires installation (electric start models include the system pre-installed from the factory). We recommend professional installation as the flywheel must be removed to install the charging coils. If you could not or did not wish to complete the installation yourself, any marine tech should be able to complete this service for 1 hour of labor. We also offer installation of the system for an additional charge of $59.99.
ELECTRIC START MODELS: 12V CHARGING SYSTEM IS STANDARD
Electric start model engines automatically come standard with the 12V charging system pre-installed from the factory. No assembly is required. You simply connect the 8.2 ft positive/negative electric start battery leads (provided) to your battery.
- BigFoot 9.9hp Models:What is a "BigFoot" model outboard?
- ProKicker Models: What is a "ProKicker" model outboard?
9.9 BigFoot ProKicker models include all features listed above plus a larger and deeper lower unit with an over-sized anti-ventilation plate. The BigFoot lower unit also includes stronger gears, bearings and shafts and a low 2.42:1 gear ratio which offers improved handling at low speeds and best-in-class slow trolling speeds.
- Remote Models: What is a remote control model outboard?
- Remote Models: Why can't remote control models be shipped?
We offer and ship tiller models only, up to and including 20hp models.
- Saltwater Use: Are Mercury outboards salt-water rated?
For maximum durability and corrosion protection, all Mercury outboards feature:
- High Grade Marine Alloy Construction
- Stainless Steel Water Pump Housings
- Zinc Coated Internal Water Passages
- Sacrificial Zinc Anodes
- Exclusive Multi-Layer Protective Coating
- Freshwater Flush: How do you recommend I flush my outboard?
Caution: To avoid injury in the event of accidental starting, be sure to remove the prop and the stop switch lanyard cord from your outboard before proceeding.
Important: All Mercury outboards are water cooled; running your outboard without an adequate source of cooling water will result in severe damage to your outboard.
2.5, 3.5, 4, 5, & 6hp:
For smaller outboards, the simplest way to flush your outboard is by using a large container of water (bucket, pail, barrel). Be sure the container is large enough to completely cover the water intake ports on the lower unit of the outboard. Also be sure that the container is wide enough so that no part of the motor will touch the sides/bottom of the bucket. Securely mount your outboard on a sawhorse or other sturdy device that will allow safe operation of your outboard. You may also use an optional "flushing plug", see below.
8hp and up:
With 8hp-140hp outboards we recommend you use a motor flusher ("ear muffs"). This type of motor flusher is easy to use, inexpensive, and available at virtually every marine retailer. This equipment attaches to your garden hose and clamps on to your outboard's lower unit, covering the water intake ports. Turn the garden hose on fully before starting your engine. Make sure the "ear muff" motor flusher is firmly in place and correctly positioned over the water intakes on your lower unit. (Note: the "ear muff" motor flusher will not work on outboards below 8hp)
Run your outboard at normal idle speed for 5-10 minutes to allow the engine to warm up and to ensure your outboard is thoroughly flushed with clean water. DO NOT rev up the engine as this is not necessary for flushing and could cause damage to the water pump.
Flushing Plug Attachment:
The flushing plug attachment is available for all outboards ($19.99). It is a bit cumbersome to use and requires removal of a water bolt on the engine. Once the water bolt is removed, the flushing attachment can be used. After flushing, the flushing attachment is removed and the water bolt is re-installed. When using the flushing plug method, the engine should NOT be operated while flushing.
- Break-In: What is the break-in procedure for my new outboard?
- Warranty: How does the Mercury warranty work?
Mercury Marine 3-Year Warranty (included)
Mercury outboards are backed by Mercury Marine's 3-year warranty. Warranty service is available through any U.S. authorized Mercury Marine dealer or service center. If you need help locating a service center in your area, please email us and include your zip code. These service centers can also provide service after the warranty period.
- First Use: Is there anything I need to do before using my outboard?
Engine oil must be added prior to use. The engine oil is drained prior to shipping. When your new outboard arrives, you simply add engine oil (see owner's manual for oil type and capacity for your model). The lower unit gear lube is pre-filled from the factory. No assembly is required. Even the propeller is pre-installed for your convenience.
If you purchase an electric start model, your outboard will include battery leads pre-installed from the factory (battery not included). You simply connect the battery leads to your battery.
Read the owner's manual carefully prior to operation. The owner's manual contains important information regarding the break-in period, safety and proper use of your outboard engine.
- Placing Your Order: What are the benefits of ordering online?
- Online checkout is quick, convenient, and 100% secure
- Order anytime: 24 hours a day, 7 days per week!
- Receive an instant order confirmation
- Online orders are sent directly to our warehouse for priority processing
- Tracking information is automatically emailed when order is shipped
- Payment Methods: What types of payment do you accept?
Check Payments: Personal Checks, Money Orders, or
Bank Checks (cashier's checks) are accepted.
All check types and money orders are subject to a clearing period of 5-7 business days prior to order shipment.
Prior to mailing a check or money order,, contact us by phone to place your order. You will receive an order confirmation number which must be included with your check/money order..
- Free Shipping: Is shipping free within the lower 48 states? AK/HI?
Shipping to Alaska and Hawaii is additional. For AK/HI shipping cost, visit the product page for the specific model you are interested in and click the "Shipping Information" tab.
We do not ship outside the U.S. per mfg. restrictions.
- Shipping Time: How long will it take for my outboard to arrive?
- Tracking Info: How is tracking information provided?
- Freight Damage: What do I do if my outboard is damaged in transit?
NOTE: If your engine is being delivered via motor freight (truck freight), be sure to note crate or engine damage on the bill of lading when signing for the shipment.
- Shipping Outside U.S.: Do you ship outside the U.S.?
- No Sales Tax: Do you collect sales tax outside of TN?
- Tennessee Orders: Is tax added if I pick-up my outboard in TN?
- Warranty Registration Card: What is your Dealer Code/Name?
- Trade-Ins: Do you accept trade-ins?
- Used/Non-Current: Do you sell used or non-current outboards?
- Our Location: Where is your dealership located? (Cookeville, TN)
202 Dragon Drive
Dickson, TN 37055