Drive Belt Tensioner Replacement Cost - RepairPal EstimateDrive Belt Tensioner Replacement costs between $127 and $381 on average. Get a free detailed estimate for a repair in your area.tensioner change in electric grinder,How to Replace the Brushes on a Makita Grinder--A Quick Fix .Nov 29, 2011 . Brushes are some of the first parts to fail in any power tool. If your tool isn't running, brushes are very likely to blame. Luckily, you can easily replace .