Mercury Verado V10 5.7 L (350 / 400 / 400R / 425, SeaPro 350) service guide

Quick answers

How much oil does a Mercury Verado V10 5.7 L take?

9.5 L (10.0 US qt) with filter.

What engine oil does a Mercury Verado V10 5.7 L use?

Verado 350/400/425 and SeaPro 350: NMMA FC-W SAE 25W-40. 400R: NMMA FC-W SAE 25W-50.

What gear oil does a Mercury Verado V10 5.7 L use, and how much?

SAE 85W-90 Extreme Performance Gear Lube (API GL-4) in all gearcases; do not mix. Quantity: 6.4 in.: RH 1580 ml (53.4 fl oz), LH 1380 ml (46.7 fl oz). 5.44 in. HD: 813 to 858 ml (27.5 to 29.0 fl oz). Sport Master: 621 ml (21 fl oz).

What spark plug does a Mercury Verado V10 5.7 L use?

NGK LKAR7C-9, 14 mm hex. Gap: 0.9 mm (0.035 in.).

How often should a Mercury Verado V10 5.7 L be serviced?

The factory schedule lists: Every 100 hours or once a year; Every 300 hours or 3 years; Every 1,000 hours. 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 Mercury Verado V10 5.7 L?

The factory schedule says to replace it at 300 hours. In Hawaiʻi's warm salt water we replace it every 200 hours or 1 year, whichever comes first, because a worn impeller is the most common cause of overheating.

What is the idle speed of a Mercury Verado V10 5.7 L?

650 r/min in neutral, warm; idle charge up to 775 r/min; troll 550 to 1,000 r/min.

What is the propeller nut torque on a Mercury Verado V10 5.7 L?

Revolution X with Flo-Torq X hub: locknut 135.6 N·m (100 lb·ft). 1-1/4 in. shaft with HD hub: brass hex nut 115.2 N·m (85 lb·ft), then locknut 115.2 N·m (85 lb·ft).

Maintenance specs

Engine oil	Verado 350/400/425 and SeaPro 350: NMMA FC-W SAE 25W-40. 400R: NMMA FC-W SAE 25W-50
Engine oil quantity	9.5 L (10.0 US qt) with filter
Oil filter	Oil the gasket, then 3/4 to 1 turn after it touches
Oil drain valve	15 N·m (132.7 lb·in); loosen no more than 2-1/2 turns
Gear lubricant	SAE 85W-90 Extreme Performance Gear Lube (API GL-4) in all gearcases; do not mix
Gearcase capacity	6.4 in.: RH 1580 ml (53.4 fl oz), LH 1380 ml (46.7 fl oz). 5.44 in. HD: 813 to 858 ml (27.5 to 29.0 fl oz). Sport Master: 621 ml (21 fl oz)
Gear fill/drain and vent plugs	11.3 N·m (100 lb·in)
Gearcase pressure test (no lube)	6.4 in.: 103.4 kPa (15 psi), 15 minutes. 5.44 in. HD and Sport Master: 103.4 kPa (15 psi), 5 minutes
Spark plug	NGK LKAR7C-9, 14 mm hex
Spark plug gap	0.9 mm (0.035 in.)
Idle speed	650 r/min in neutral, warm; idle charge up to 775 r/min; troll 550 to 1,000 r/min
Thermostats	Main: starts 59 to 61 °C, fully open 70 °C (158 °F), stroke at least 9.5 mm. Crankcase cooler: starts 49 to 52 °C, fully open 60 °C (140 °F), stroke at least 5.0 mm
Water pressure	650 r/min 5 to 10 kPa (0.7 to 1.5 psi), hot 0 to 5 kPa; 6400 r/min 35 to 260 kPa (5.1 to 37.7 psi)
Anode screws	Gearcase anode M10 x 25 screws 54.2 N·m (40 lb·ft); Sport Master anode plate screws 54.23 N·m (40 lb·ft); trim manifold anode screws 5.5 N·m (49 lb·in)
Propeller nut	Revolution X with Flo-Torq X hub: locknut 135.6 N·m (100 lb·ft). 1-1/4 in. shaft with HD hub: brass hex nut 115.2 N·m (85 lb·ft), then locknut 115.2 N·m (85 lb·ft)
Power trim fluid	Power Trim and Steering Fluid, or ATF Type F, FA, Dexron II or III; about 25 mm (1 in.) below the top of the fill neck; cap 1/4 turn
Valve lash clearance	IN 0.125 to 0.225 mm (0.005 to 0.009 in.); EX 0.300 to 0.400 mm (0.012 to 0.016 in.)

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.

1. Every 100 hours or once a year

   Replace: engine oil, oil filter, oil drain plug gasket, gear case oil, gear case plug gaskets

   Check: fuel filter, thermostat, anodes

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

   Replace: engine oil, oil filter, oil drain plug gasket, gear case oil, gear case plug gaskets, water pump impeller

   Check: fuel filter, thermostat, anodes

3. Every 300 hours or 3 years

   Replace: engine oil, oil filter, oil drain plug gasket, spark plugs, fuel filter, gear case oil, gear case plug gaskets, water pump impeller

   Check: thermostat, anodes

4. Every 1,000 hours

   Replace: engine oil, oil filter, oil drain plug gasket, gear case oil, gear case plug gaskets, water pump impeller

   Check: fuel filter, thermostat, anodes

We replace the water pump impeller at every service from 200 hours up, which can be sooner than the factory schedule, because of Hawaiʻi’s warm salt water.

Source: Mercury 5.7L V10 350/400/425 Verado and 350 SeaPro service manual, 90-8M0237329. Specs can change by model year and serial number, so always confirm your exact model from the serial tag on the clamp bracket.