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Alternator replacement on these vans is not too simple due to clearance issues.
Once you remove the belt, disconnect the battery, and remove the bolts securing the alternator, there is insufficient room to get the alternator out of the engine bay. Easiest thing to do is to jack the van up and place jackstands under the body pinch weld just behind the front wheels. Then place jack under the front suspension subframe on the passenger side. Remove the front and rear subframe bolt, then use the jack to lower the subframe and engine from the van slightly. This will give you enough clearance to remove the alternator over the top of the engine.
An alternate method is listed below.
1. Remove the generator from the generator bracket and position the generator above the drive axle.
2. Remove the drive belt tensioner.
3. Remove the generator bracket.
4. Remove the power steering pipes from the power steering pipe retainer.
5. Remove the fuel pressure test port (schrader valve) cap from the fuel injector rail. IMPORTANT
: Do not disconnect the power steering pipes from the power steering pump.
6. Remove the power steering pump and reposition the power steering pump in front of the timing chain cover in order to provide access for the generator.
7. Remove the generator from the vehicle