What two-stroke oil does a Suzuki DT55 / DT65 two-stroke use?

Suzuki CCI oil or an NMMA certified 2-stroke lubricant; if neither is available, use only 2-stroke outboard oil.

What is the fuel to oil ratio for a Suzuki DT55 / DT65 two-stroke?

Oil injection, variable ratio: about 150:1 fuel to oil at idle, changing gradually to 50:1 at full throttle.

What gear oil does a Suzuki DT55 / DT65 two-stroke use, and how much?

Suzuki Outboard Motor Gear Oil or an equivalent high quality SAE 90 hypoid gear oil. Quantity: 22 oz (650 ml).

What spark plug does a Suzuki DT55 / DT65 two-stroke use?

NGK B8HS-10, DT55 and DT65, 1988 to 1997 (Champion L4J, RL4J, L78, RL78). Qty 3. Gap: DT55: 0.035 to 0.039 in (0.9 to 1.0 mm).

How often should a Suzuki DT55 / DT65 two-stroke be serviced?

The factory schedule lists: First 10 hours or 1 month; Every 50 hours or 3 months; Every 100 hours or 6 months. In Hawaiʻi's salt water we do a full yearly service every 200 hours or 1 year, whichever comes first, and a new engine needs its first (break-in) service.

When should the water pump impeller be replaced on a Suzuki DT55 / DT65 two-stroke?

The factory schedule says to replace it at 100 hours, and we follow that. In any case we never let it go longer than a year in Hawaiʻi's salt water.

What is the idle speed of a Suzuki DT55 / DT65 two-stroke?

DT55 1988-90: 650 to 700 rpm; DT55 1991-97: 750 to 800 rpm. DT65: 650 to 700 rpm.

Suzuki DT55 / DT65 two-stroke (1988-1997, oil injected) service guide

Oil, gear oil, spark plugs and the service schedule for the Suzuki DT55 / DT65 two-stroke (1988-1997, oil injected) (55 to 65 hp, two-stroke), from the factory service manual, plus how we service it in Hawaiʻi.

Models covered: DT55 and DT65, 1988 to 1997: inline 3 cylinder, 54.4 cu in (891 cc), bore and stroke 2.87 x 2.80 in, oil injection, Digital I.C. ignition (several DT55 rows say Suzuki P.E.I.), electric start with electric choke.

Quick answers

What two-stroke oil does a Suzuki DT55 / DT65 two-stroke use?: Suzuki CCI oil or an NMMA certified 2-stroke lubricant; if neither is available, use only 2-stroke outboard oil.
What is the fuel to oil ratio for a Suzuki DT55 / DT65 two-stroke?: Oil injection, variable ratio: about 150:1 fuel to oil at idle, changing gradually to 50:1 at full throttle.
What gear oil does a Suzuki DT55 / DT65 two-stroke use, and how much?: Suzuki Outboard Motor Gear Oil or an equivalent high quality SAE 90 hypoid gear oil. Quantity: 22 oz (650 ml).
What spark plug does a Suzuki DT55 / DT65 two-stroke use?: NGK B8HS-10, DT55 and DT65, 1988 to 1997 (Champion L4J, RL4J, L78, RL78). Qty 3. Gap: DT55: 0.035 to 0.039 in (0.9 to 1.0 mm).
How often should a Suzuki DT55 / DT65 two-stroke be serviced?: The factory schedule lists: First 10 hours or 1 month; Every 50 hours or 3 months; Every 100 hours or 6 months. In Hawaiʻi's salt water we do a full yearly service every 200 hours or 1 year, whichever comes first, and a new engine needs its first (break-in) service.
When should the water pump impeller be replaced on a Suzuki DT55 / DT65 two-stroke?: The factory schedule says to replace it at 100 hours, and we follow that. In any case we never let it go longer than a year in Hawaiʻi's salt water.
What is the idle speed of a Suzuki DT55 / DT65 two-stroke?: DT55 1988-90: 650 to 700 rpm; DT55 1991-97: 750 to 800 rpm. DT65: 650 to 700 rpm.

Maintenance specs

Injection oil	Suzuki CCI oil or an NMMA certified 2-stroke lubricant; if neither is available, use only 2-stroke outboard oil
Oil tank	3.2 quarts (3.0 liters)
Fuel to oil ratio	Oil injection, variable ratio: about 150:1 fuel to oil at idle, changing gradually to 50:1 at full throttle
Gear oil	Suzuki Outboard Motor Gear Oil or an equivalent high quality SAE 90 hypoid gear oil
Gear oil quantity	22 oz (650 ml)
Gear oil drain (fill) plug and oil level plug	Loosen the oil level plug first, then remove the fill (drain) plug at the lower end of the gear housing, then the oil level plug. Check the magnet end of the drain screw for metal. Use new gaskets (washers); install the oil level and vent plugs (if fitted) first, then the fill plug.
Lower unit pressure test	16 to 18 psi of air, submerged or sprayed with soapy water; then 3 to 5 inches of vacuum; hold each for a few minutes
Spark plug	NGK B8HS-10, DT55 and DT65, 1988 to 1997 (Champion L4J, RL4J, L78, RL78). Qty 3
Spark plug gap	DT55: 0.035 to 0.039 in (0.9 to 1.0 mm).
Spark plug torque	10 to 15 ft-lb (14 to 20 N·m) with a new crush washer, or about 1/4 turn to crush the washer.
Idle speed	DT55 1988-90: 650 to 700 rpm; DT55 1991-97: 750 to 800 rpm. DT65: 650 to 700 rpm

Service schedule

The factory maintenance intervals, with what is replaced and what is checked at each. Rows marked Hawaiʻi are our shop's yearly service for salt water use.

First 10 hours or 1 month

Replace: gear case oil, gear case plug gaskets, propeller cotter pin
Every 50 hours or 3 months

Replace: gear case plug gaskets

Check: fuel filter, anodes
Every 100 hours or 6 months

Replace: gear case oil, gear case plug gaskets, propeller cotter pin, water pump impeller

Check: spark plugs, fuel filter, anodes
Every 200 hours or 1 year (our Hawai‘i yearly service) Hawai‘i

Replace: gear case oil, gear case plug gaskets, propeller cotter pin, water pump impeller

Check: spark plugs, fuel filter, anodes

Source: Suzuki DT 2 to 225 hp two-stroke outboards service manual. Specs can change by model year and serial number, so always confirm your exact model from the serial tag on the clamp bracket.

Suzuki DT55 / DT65 two-stroke (1988-1997, oil injected) service guide

Quick answers

Maintenance specs

Service schedule

First 10 hours or 1 month

Every 50 hours or 3 months

Every 100 hours or 6 months

Every 200 hours or 1 year (our Hawai‘i yearly service) Hawai‘i

Other Suzuki guides