Take it apart, install new shaft bushings and brushes. Check diodes and regulator, replace any defective components.
Front, drivers side , below engine
under the intake manifold you have to remove the engine cover to get to it.
Which engine?
It depends what is wrong with the engine.
The starter for a 1998 Cavalier is mounted on the side of the engine. It is at the rear, near the bottom.
The 1998 most likely has a Northstar engine. On this engine the starter is under the intake, and the intake has to come off for replacement.
The 3.4 liter V6 engine in a 1998 Oldsmobile Silhouette has a timing CHAIN
The starter is on the radiator side of the engine, behind the engine mount bracket.
the starter is located on the right side of the engine.
starter is located next to engine at front of transmissin
on bottom side of engine
4.6 US quarts