First disconnect the battery so you won't mess with live wires. Now there should be two bolts holding the alternator on, the one on bottom is long and the top one is short. Loosen the top bolt first and the alternator will pivot down and the belt will come off. Undo the bottom bolt and then unplug the wiring harnesses from the back or the alternator. Put your new one on the same way you took the old one off, adjust it to get the belt tight, then connect your battery.
The Ford Ranger alternator bolt torque specification is dependent upon the year of the Ford Ranger. In general, the alternator bolt torque specification is 45 pounds.
how do you change outer tie rods on a 1990 ford ranger
No
A 1990 Ford Ranger is OBD I / EEC IV - if that's what you are asking
location of fusable links Ford Ranger 1990 2.9
spark plug gap on 1990 ford ranger 4.0?
is there a picture of where the horn fuse is located on a 1990 ford ranger
No. From 1983-84 Ford used the C3 transmission. A 1990 will not fit.
Wikipedia has a great history of the ford ranger line.
where is the fuel filter located on a 1990 ford ranger 2.3 L engine
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1990 ford ranger 2.3 no injector pulse what causes this