1994 nissan pathfinder v-6 4x4. Starter clicks when you turn the key. Will start occasionally. Replaced starter and nothing changed. Sounds like the starter is hitting the flywheel and not engaging. When the starter is loosened and moved about an inch out the starter will spin. Is there a shim proceedure for the starter (there is no access port on the bellhousing for the flywheel) or is the flywheel bad or what? Please help.