1986 Mustang Engine Information – 232 cubic inch V6 (3.8L Ford Essex V6)
The Ford Essex V6
The 3.8 L Essex V6 replaced the 3.3 L I6, as the 3.3 L engine had little demand and was dropped after 1982. The 3.8 liter engine was used from 1983 to 1986, it was then dropped from the Mustang line. It reappears as a Mustang engine in 1994 and is used until 2004, replaced by the 4.0 liter engine in 2005.
Central Fuel Injection was made available in 1984. Output was 120 hp (89 kW) at 3600 rpm and 205 lb⋅ft (278 N⋅m) of torque at 1600 rpm in these models. This carried over into the 1985 and 1986 model year we are talking about here.
Engine Basics
Year
1986
Cylinders
6
Displacement
232 cu / 3.8 liters
Power (hp)
120 hp @ 3,600 RPM
Torque (lb/ft)
205 lb/ft @ 1,600 RPM
Compression
9.0:1
Bore x Stroke
3.81 × 3.39
3.8 Liter Engine Specs
Firing Order: 1-4-2-5-3-6
LH cylinders front to rear: 1-2-3
RH cylinders front to rear: 4-5-6
Valve order left head: E-I-E-I-E-I
Valve order right head: I-E-I-E-IE
Cylinder compression pressure: 101 PSI minimum
1983 & 1984 Oil pressure: 2500 rpm and warm 55-60 PSI
1985 Oil pressure: 2500 rpm and warm 40-60 PSI
Spark plugs: AWSF54-C @0.054″
Thermostat starts to open: 193-200 degrees
Thermostat fully open: 221 degrees
Radiator cap pressure: 16
Cylinder head warp limit .007 “
Engine & Other Torque Specifications
All torque specifications provided in this table are those recommended by FORD. If you use special bolts, follow the torque specifications provided by the manufacturer. I recommend that you use the 3 step torque technique where you torque down the bolts in three equal steps. Once you have reached the maximum recommended torque setting, go around one more time. Do not torque in a circular pattern. Always torque cross to cross.
Head bolts 1984 & up
35-45-55-60
Head bolts 1983
45-55-65-75
Rod end caps
31-36
Intake bolts
5-10-18
Exhaust manifold bolts
15-22
Harmonic damper
93-121
A/C Compressor mounts
Pressure plate to flywheel
12-24
Motor mounts to engine
Bellhousing to engine bolts
28-38
Trans to bellhousing
Flywheel to Crankshaft
54-64
Auto Transmission to motor block 4 & 6 cylinders
28-38
Auto Transmission to motor block 8 cylinders
40-50
Crankshaft pulley to Harmonic balancer
20-28
Vibration damper bolt
Camshaft Sprocket
15-22
Timing chain cover bolts
15-22
fuel pump to block 12-15
neutral start switch C3 1979-1981
12-15
neutral start switch C3 1982 – 1986
7-10
neutral start switch C4
6-8
neutral start switch C5
55-75 “/lbs
neutral start switch C3 1982 – 1986
84-120 “/lbs
neutral start switch AOD
8-11 lbs
Auto transmission pan bolts C3
12-17
Auto transmission pan bolts C4 & C5
12-16
Auto transmission pan bolts A4LD
8-10
Auto transmission pan bolts AOD
6-10
Oil pan bolts
12
Valve cover bolts
10
Carburetor mount bolts
Oil pump
18-22
Oil pan drain plug
15-25
Trans. inspection plate
Water pump bolts
15-22
Clutch pressure plate
Spark plugs
5-11
engine block drain plug
5-8
Rocker arms
8 -18 to 25
Main cap bolts
65-81
Rocker arm cover to cylinder head (screw)
31-61 inch pounds
Rocker arm cover to cylinder head (bolt/stud
80-106 inch pounds
Carb to intake 5200/6500
10-14
Carb to intake model YFA 1v
13-14
Carb to intake 2150 2V
14-16
Carb to intake model 7200 VV
12-15
Carb to intake 4180-C 4V
14-20
Driveshaft flange bolts
70-95
Pedal support brake bracket
13-25
Clutch self adjuster bolt
17-26
Wheel lug nuts
80-105
Front hub nut
17-25, back off then to 10-15 lbs
Valve information
Minimum valve margin width
1/32″
Intake & exhaust valve seat angle
45 degrees
Intake & exhaust valve face angle
44 degrees
Intake & exhaust valve face runout limit
0.002″
Intake & exhaust valve seat width
0.060 – 0.080
Intake & exhaust valve seat runout limit
0.003
Intake stem diameter
0.3423-0.3716
Exhaust stem diameter
0.3418-0.3411
Intake valve stem to guide clearance
0.001-0.0027
Exhaust valve stem to guide clearance
0.0015-0.0032
1983,84,85 Valve spring pressure, valve open
215 lbs @1.29″
1983,84,85 Valve spring pressure, valve closed
75 lbs @ 1.70″
1986 Valve spring pressure, valve open
190 @ 1.28″
1986 Valve spring pressure, valve closed
73 @ 1.70″
Service limit (all)
10 lbs loss
Valve lifter bore diameter
0.874
bore to lifter clearance std.
0.0007 – 0.0027
Service limit
0.005″
Crankshaft Specifications
Connecting rod journal diameter
2.3103-2.3111″
Connecting rod journal out-of-round
0.0003″
Connecting rod journal taper limit
0.0003″ per inch
Connecting rod Bearing oil clearance desired
0.001-0.0014″
Connecting rod Bearing oil clearance allowed
0.00086-0.0027″
Connecting rod side clearance std.
0.0047-0.0114″
Connecting rod side clearance allowed
0.014
Main Bearing journal diameter
2.519-2.5198″
Main Bearing journal out-of-round
0.0003″
Main Bearing journal taper limit
0.0003″ per inch
Main Bearing journal oil clearance desired
0.001-0.0014″
Main Bearing journal oil clearance allowed
0.0005-0.0023″
Crankshaft endplay
0.004-0.008″
Cylinder bore diameter
3.810″
Cylinder bore out-ofround limit
0.002″
Cylinder bore taper limit
0.002″
Piston diameter coded red
3.8095-3.8101″
Piston diameter coded blue
3.8107-3.8113″
Piston diameter coded yellow
3.8119-3.8125″
piston to bore clearance 1983
0.0014-0.0022
piston to bore clearance 1984,5,6
0.0014-0.0032″
Piston ring end gap compression ring
0.010-0.020″
Piston ring end gap oil ring
0.015-0.0583″
Piston ring side clearance
0.0016-0.0037″