Nissan 8 Hp NSF8A31 Outboard Motor

Description

We have the Nissan NSF8A31 for sale here, a 8 HP Nissan four stroke outboard built by Tohatsu. Nissan stopped selling outboards a few years ago, but the motor itself is a Tohatsu MFS8A3 under a Nissan cowl, so parts and know-how are still easy to find.

We sell outboards to boat owners, fishing guides, sailing schools, resorts and dealers, and we ship worldwide. Tell us where you are and we send a delivery quote before you pay anything. We also confirm the condition, model year and shaft length of the Nissan NSF8A31 for sale with photos before it ships.

Everything is on this page: specifications, the model code, boats it suits, how it runs, maintenance, delivery and a short FAQ.

Nissan NSF8A31 for sale: Specifications

Figures are for the NSF8A3 family. Small details can differ between production years, so we check the plate on the motor before we confirm your order. Tohatsu lists the current versions of this motor on its current Tohatsu outboard range.

What the Model Code on the Nissan NSF8A31 for sale Means

NSF is Nissan for a four stroke outboard, the same way Tohatsu uses MFS. 8 is the horsepower. The series code after the horsepower, A3, marks the model series. The rest of the code, 1, identifies the version in this listing. When you order, we read the full model and serial plate on the bracket and send you a photo, so there is no guessing.

Nissan and Tohatsu: Same Motor, Different Badge

For many years Tohatsu, one of the oldest outboard makers in Japan, built Nissan Marine outboards alongside its own. The NSF8A3 and the Tohatsu MFS8A3 came off the same production line. Apart from the decals, the cowl colour and the model code, they are the same motor.

That matters when you buy a Nissan today. Service manuals, filters, impellers, plugs and gearcase parts are shared with the Tohatsu twin, so any Tohatsu dealer can look after the Nissan NSF8A31 for sale. Most parts catalogues list both codes side by side.

Inside the 209 cc Twin: the Nissan NSF8A31 for sale

The Nissan 8 and 9.8 HP motors of the A3 series use a 209 cc two cylinder four stroke with a belt driven overhead camshaft. Tohatsu built it as the MFS8A3 and MFS9.8A3, and it was one of the lightest motors in its class when it came out.

Two cylinders make a big difference at this size. The Nissan NSF8A31 for sale runs smoother and quieter than a single, with less vibration through the tiller and the transom. A rev limiter cuts in at 6,250 rpm, and if oil pressure drops the motor slows itself to about 3,000 rpm so you notice before damage is done.

The gearcase uses a 2.08:1 ratio with forward, neutral and reverse. Six trim positions and a shallow water setting let you run over sandbars and weed with the leg tilted up. A 12 V, 6 A charging coil keeps a battery topped up while you run.

Boats That Suit the Nissan NSF8A31 for sale

Aluminium fishing boats

Boats from about 3.5 to 4.5 m that need a steady, reliable push.

Inflatables and RIBs

Larger inflatables that can carry the extra weight of a twin.

Sailboat auxiliary

A strong auxiliary for small keelboats, with reverse for docking.

Kicker motor

A trolling and back up engine beside a bigger main outboard.

How the Nissan NSF8A31 for sale Runs

The Nissan NSF8A31 for sale starts easily on the pull cord, helped by the low compression feel of a small twin. Idle is smooth and quiet enough to talk over.

Out on the water the twin pulls cleanly through the range. Trolling at low revs is easy, and at full throttle it holds its speed without the shake you get from a single cylinder motor.

Nissan NSF8A31 for sale or the 9.8 HP?

The Nissan 8 and 9.8 HP A3 motors share the same 209 cc engine and the same weight. The Nissan NSF8A31 for sale costs a little less and suits lighter boats. In some places it also fits under a lower power limit for licensing or lake rules.

If you are not sure which suits your boat, send us the hull length and the usual load and we will tell you honestly.

The Nissan NSF8A31 for sale or a New Tohatsu?

If you would rather have the current version, the Tohatsu MFS8BS is the modern descendant of this motor and is also in stock. It brings the latest updates and a fresh factory warranty, at a higher price.

The Nissan NSF8A31 for sale is the value pick. You get a proven Tohatsu built engine at a lower price, and running it costs the same. Many buyers who know these motors choose the Nissan for exactly that reason.

Buying a Discontinued Model: What to Know

Nissan Marine no longer makes outboards, so there is no Nissan dealer network to back new warranty claims. In practice this rarely matters for a small four stroke, because the engine is a Tohatsu and Tohatsu dealers and parts suppliers are everywhere.

Before we ship the Nissan NSF8A31 for sale we confirm its condition, model year and serial number with photos. Ask us anything you want checked: compression, the tell tale stream, the gear oil or the prop. We would rather answer questions before the sale than after it.

Getting the Shaft Length Right

This is the most important measurement. Measure the transom height at the centre, from the top of the transom to the bottom of the hull. Around 15 inches suits a short shaft and around 20 inches a long shaft. Too short and the prop sucks air. Too long and you get drag and spray. We confirm the shaft length of the Nissan NSF8A31 for sale before you pay, so send us your transom measurement with your enquiry.

Mounting the Motor

Centre the motor on the transom and tighten the clamp screws firmly. Check them again after the first run, because they can loosen with vibration. Set the tilt pin so the motor sits upright when the boat is moving, with the anti-ventilation plate roughly level with the bottom of the hull. Tie a safety line from the motor to the boat in case a clamp ever loosens.

Your First Day Out With the Nissan NSF8A31 for sale

Pick a calm day for the first run and stay close to where you launched. Fit the kill cord to your wrist or life jacket, open the fuel vent and The A3 twins run from a separate portable tank. Keep the tank vent closed when you are not running and squeeze the primer bulb until firm before you start.

Start the motor in neutral and let it idle for a minute while you look for the stream of water from the tell tale. Spend the first hour getting a feel for the throttle, the gear lever and the steering. Practise coming alongside a buoy or a pontoon at low speed. Most people are surprised how quickly it starts to feel natural.

The First Hours After Delivery

Treat the first few hours gently, especially after the motor has been sitting in storage. Keep the Nissan NSF8A31 for sale below half throttle for the first hour and keep changing speed. After that, use more throttle in short bursts. Change the engine oil and gear oil after the first few hours so you start with a clean slate.

Maintenance on the Nissan NSF8A31 for sale

• Flush with fresh water after every trip in salt or dirty water.
• Check the engine oil level before each trip. The sump takes 0.8 L.
• Change the engine oil at the hours in the manual, or at least once a season.
• Change the gear oil every season and look for milky oil.
• Replace the water pump impeller every two to three seasons.
• Check the spark plugs and the fuel filter.
• Grease the swivel, clamp screws and tilt points.

Most owners do these jobs themselves with basic tools. Because the Nissan NSF8A31 for sale shares its parts with the Tohatsu MFS8A3, you can order by either code.

The Water Pump Impeller

Every water cooled outboard has a rubber impeller in the lower unit that pushes cooling water up to the engine. Rubber ages, and sand wears the vanes, so it needs replacing every two or three seasons, or sooner if you run in sandy water. On a motor that has been sitting, it is the first part we suggest replacing.

The first sign of trouble is a weak or missing stream from the tell tale. Stop the engine and find the cause. Running a four stroke without cooling water, even briefly, can damage it.

Why the Anodes Matter

The small metal blocks on the gearcase and bracket are sacrificial anodes. In salt or brackish water they corrode instead of the aluminium housing. Check them each time you flush the motor and swap them when they are worn to about half their size. A set of anodes costs little next to a pitted gearcase.

Changing the Gear Oil

The gearcase oil is easy to forget because you never see it. Take out the lower drain screw, then the upper vent screw, and let the old oil run into a tray. Clean dark oil is normal. Milky oil means water is getting past a seal, and that should be fixed before it rusts the gears. Refill from the bottom hole with marine gear oil until it comes out of the top, fit the vent screw, then the drain screw. New sealing washers each time are a good habit.

Fuel Quality Matters

Carburettor motors are sensitive to old fuel. Use fresh petrol, keep caps closed and add a fuel stabiliser if the Nissan NSF8A31 for sale will sit for more than a few weeks. If your fuel contains ethanol, do not leave it in the carburettor over winter. Most hard starting on small outboards comes back to stale fuel.

The A3 twins run from a separate portable tank. Keep the tank vent closed when you are not running and squeeze the primer bulb until firm before you start.

Getting the Prop Right

The full throttle range on the Nissan NSF8A31 for sale is 5,000 to 6,000 rpm with a normal load. Heavy boats usually want a lower pitch and light ones a higher pitch. A good prop shop can help you choose, and Tohatsu props for the MFS8A3 fit this motor.

Salt Water Care

Flush the motor with fresh water after every salt trip, using a flushing muff or a test tank. Rinse the outside and wipe the cowl. Spray a corrosion inhibitor under the cowl now and then. If the motor lives on a tender or a transom, tilt it up so the lower unit is out of the water.

Storage and Laying Down the Motor

Four strokes have an oil sump, so they care which way you lay them down. The correct side is shown in the owner manual and usually on a label on the motor. Lay it the wrong way and oil can run into the cylinder, which leads to smoke and hard starting.

For long storage, run the carburettor dry or drain it, change the oil, grease the fittings and keep the motor upright on a stand in a dry place. A motor stand is cheap and saves the cowl from scratches.

Common Problems and Quick Checks

• Will not start. Check the kill switch clip, the choke, the fuel vent and the primer bulb.
• Starts then stops. Usually old fuel or a closed vent.
• Weak tell tale stream. Clear the outlet with a wire. If still weak, have the impeller checked.
• Loss of power. Check the prop for damage or weed, and the fuel filter.
• Rough idle. Check the plug and clean the carburettor jets.

What to Carry in the Boat

A few spares cover most things that stop an outboard on the water: a spare plug and plug spanner, a spare kill cord, a basic tool roll, a spare prop pin or prop hardware, tape and cable ties. Add life jackets, oars or a paddle, a bailer and a phone in a dry bag. The second kill cord is the one people wish they had most.

Running Costs

Four strokes are cheap to run. They burn far less fuel than an old two stroke of the same size, and there is no two stroke oil to buy. The other costs are small: engine oil once a season, gear oil, a plug now and then and an impeller every few years. Over a few seasons the fuel savings alone go a long way toward the price of the Nissan NSF8A31 for sale.

Matching the Motor to the Boat

The capacity plate near the transom tells you the maximum power and weight your boat is built for. Stay within it. Inside that limit, think about the load you carry, how far you go and the water you use. More power helps with heavy loads, wind and current. Less power saves weight, fuel and money. If the Nissan NSF8A31 for sale sits near the top of your boat rating, it will feel lively. If it sits near the bottom, expect a relaxed, economical cruise.

Moving Up From a Two Stroke

If you are replacing an old two stroke, expect less noise, no smoke, no oil mixing and lower fuel bills. Servicing changes to simple oil changes, much like a car engine. The trade is a little more weight, which most boats handle easily. Owners who switch rarely want to go back, mostly because of how quiet the motor is at trolling speed.

Steering and Throttle Feel

The twist grip throttle and tiller arm give you direct control. Set the steering friction so the motor stays put when you let go, but still turns without effort. Remember that an outboard steers by pushing the stern sideways, so the back of the boat swings out when you turn. In a marina, slow down early and practise a few stops in open water first.

Who Buys the Nissan NSF8A31 for sale

We ship this kind of motor to weekend boaters, yacht owners who need a tender motor, anglers who want a reliable push or a kicker, and small businesses that run boats every day. Some order one motor, some order several. Every order gets the same treatment: we confirm the exact model, send photos, quote delivery and keep you updated until it arrives.

How Delivery Works

We ship worldwide. Once you confirm the order, the Nissan NSF8A31 for sale is drained, packed securely and booked with a carrier we trust or your own forwarder. You get the paperwork and a tracking number so you can follow it all the way. We quote the full delivery cost for your country before you pay.

Serial Number and Records

Write down the serial number from the bracket plate as soon as the motor arrives and take a photo of it. You will need it for ordering the right parts and for insurance. Some countries need outboards registered with the boat, so check the rules where you use it. A motor lock on the clamp screws is a good idea too.

A Short Checklist Before Buying

• Transom measured, so we can match the shaft length.
• Boat capacity plate checked for power and weight.
• Starting type decided.
• Delivery address sent to us.

Send us that and we will come back with photos of the motor and a full price to your door.

Buying the Nissan NSF8A31 for sale From Us

The price is on this page. Before we ship, we give you a delivery quote for your country and send photos of the exact motor. Our refund and return policy and terms and conditions are on the site. You can read what other buyers say on our reviews page, learn more on our about us page, or go straight to the contact page.

Other Nissan Outboards to Compare

• Nissan NSF8A3EF2 for sale
• Nissan NSF9.8A31 for sale
• Nissan NSF9.8A32 for sale
• Nissan NSF9.8A3EPT2 for sale
• All 8 HP Nissan outboards
• All Nissan outboard motors
• Tohatsu outboards
• The full shop

Our blog has more on looking after outboards.

FAQ: Nissan NSF8A31 for sale

Is the Nissan NSF8A31 for sale a real Nissan?

Yes. It is a Nissan badged NSF8A3 built by Tohatsu, the same motor as the Tohatsu MFS8A3.

Can I still get parts?

Yes. Parts are shared with the Tohatsu MFS8A3 and are available worldwide.

How heavy is the Nissan NSF8A31 for sale?

About 37 kg (82 lb) for the short shaft tiller version.

What engine does it have?

4-stroke, 2 cylinder, belt driven overhead camshaft, 209 cc (12.8 cu in).

How does it start?

Manual recoil start.

What shaft length is it?

We confirm it for this exact motor before you pay: 15 inch short or 20 inch long.

Do you ship the Nissan NSF8A31 for sale worldwide?

Yes. Send us your location and we will quote delivery.

Final Word

If you want a proven, Tohatsu built 8 HP four stroke at a fair price, the Nissan NSF8A31 for sale is a smart choice. Order today, or message us first with your boat details and we will help you make sure it is the right fit.