True, the ring on the plunger often gets too worn to make solid contact with the contacts. I went to toyota and was told you couldn't get a replacement plunger, then called my brother at a lithia toyota and he found it pretty easilly. I suggest updating to the Nippon Denso gear reduction starter if you have the big, cumbersome old style. They're easy to find parts for and are used on a ton of different apps/brands.
