MerCruiser 3.0L Longblocks

MerCruiser 3.0L Bobtail Engines

MerCruiser 3.0L Engine Diagrams

PART NUMBER

DESCRIPTION

Quicksilver Perfect Seal

92-34227-1

Quicksilver 2-C-4 Marine Lubricant with Teflon

92-825407A3

Quicksilver RTV Sealer

92-91601-1

DESCRIPTION

Lb. In.

Lb. Ft.

N^.m

Camshaft Sprocket Bolts

80

9

Connecting Rod Cap Nuts

45

61

Cylinder Head Bolts

90 (Note 1)

122 (Note 1)

Distributor Clamp

20

27

Marine Engine Coupler to Flywheel

35

47

Flywheel Housing to Block

21

28

Flywheel to Crankshaft Bolts

65

88

Front Cover Bolts

30

3.4

Front Mount to Block

21

28

Main Bearing Cap Bolts

65

88

Manifold to Head

23 (Note 2)

31 (Note 2)

Oil Pan Bolts-Crankcase

80

9

Oil Pan Bolts-to Front Cover

45

5

Oil Pan Studs to Oil Seal Retainer or Crankcase

15

1.7

Oil Pump Cover

72

8

Oil Pump to Block

120

14

Oil Pump Pickup

60

7

Rocker Arm Cover and Bolts

40

4.5

Rear Crankshaft Oil Seal Retainer Nuts

135

15

Spark Plugs

22

30

Starter Motor to Block

37

50

Timing Gear Cover

72

8

Torsional Damper Bolt

50

68

Water Pump to Block

15

20

UNIT OF MEASUREMENT

In. (mm)

Diameter

3.9995-4.0025(101.588-101.790)

Out of Round

Production

.0005(0.012) Max

Service

.002(0.05) Max

Taper

Production

Thrust Side

.0005(0.012) Max

Relief Side

.0005(0.012) Max

Service

.001(0.02) Max

Production

.0025-.0035(0.064-0.088) Max

Service

.0035(0.08) Max

Groove

Clearance

Production

Top

.0012-.0029(0.030-0.073)

2^nd

Service

.003(0.09) Max

Gap

Production

Top

.010-.020(0.254-0.762)

2^nd

Service

.035(0.88) Max

Groove Clearance

Production

.001-.006(0.026-0.152)

Service Limit

.007(0.17) Max

Gap

Production

.010-.030(0.254-0.762) Max

Service Limit

.040(1.01) Max

Diameter

.9270-.9271(23.546-23.550)

Clearance

Production

.0003-.0006(0.008-0.016)

Service Limit

.001(0.02) Max

Fit in Rod

.0008-.0019(0.020-0.050) Interference

Main Journal

Diameter

2.2979-2.294(58.367-58.404)

Taper

Production

.0002(0.005) Max

Service

.001(0.02) Max

Out of Round

Production

.0002(0.005) Max

Service

.001(0.02) Max

Main Bearing

Clearance

Production

.001-.0024(0.025-0.060)

Service

No. 5

.0016-.0035(0.041-0.088)

Production

.001-.0025(0.03-0.06)

Service

No. 5

.002-.0035(0.05-0.08)

Crankshaft End Play

.002-.006(0.05-0.15)

Crankpin

Diameter

2.09980-2.0995(53.289-53.327)

Taper

Production

.0003(0.007) Max

Service

.001(0.02) Max

Out of Round

Production

.0002(0.51) Max

Service

.001(0.02) Max

Rod Bearing

Clearance

Production

.0017-.0027(0.044-0.0686)

Service

N/A

Rod Size Clearance

.006-.017(0.153-0.4318) Max

Lobe Lift (Max.)

Intake

.2529(6.425)

Exhaust

.2529(6.425)

Journal Diameter

1.8677-1.8697(47.440-47.490)

Camshaft End Play

.003-.008(0.08-0.2032) Max

Gasket Surface Flatness

.003-.008 in any 6 in. (152)

or .007(0.15) Overall Maximum

Lifter

Hydraulic

Rocker Arm Ratio

1.75 to 1

Collapsed Tappet Gap

¾ Turn Down from Zero Lash

Face Angle

Intake

45^o

Exhaust

45^o

Seat Angle (Intake & Exhaust)

46^o

Seat Runout (Intake and Exhaust)

.002(0.05) Max

Seat Width

Intake

1/16 [.0625] in. (1.16 mm)

Exhaust

1/16-5/64[.0625-.07812] in. (1.6-2.0 mm)

Stem

Clearance

Production

Intake

.0010-.0027(0.025-0.069)

Exhaust

.0007-.0027(0.018-0.069)

Service

Intake

.003(0.09) Max

Exhaust

.004(0.11) Max

Spring

Free Length

2-1/16(52)

Pressure

Valve Closed

100-110 lb. (136-149 N) at 1-19/32 in. (41 mm)

Valve Open

208-220 lb. (282-300 N) at 1-7/32 in. (31 mm)

Installed Height+

.031(8)

Intake

1/32[1.6562] (42)

Exhaust

Internal Damper

None