Posted by Rick Gilley on July 10, 2007 at 12:49:13:
1981 Mastercraft. About 1600 hrs. Transmission never worked on. Was laying on the throttle heavy for about five miles. When I pulled the throttle back new noise. Has the rocks in coffee can sound in the planitary reduction area at rear of tranmission. Pulled prop shaft and ran engine on trailer. When you drop it in gear, bad noise. Throttle up the RPM and it goes away. Have forward and reverse. Pulled transmission and reduction case bearings looked good and fluid level was good. Pulled transmission and damper plate "looked" good. My damper plate has totally enclosed springs but rivits are tight and spline area tight. Don't think there is a motor problem but will folllow other advice and do a compression test.Can there be other problems inside transmission other than damper plate or engine problems that can make that horrible noise that goes away with increased RPM? Thanks!!!!!!!!