View Full Version : Kazkaki KM4A transmission problems

04-18-2009, 08:27 AM
we have two 26' Crosby Launches fitted with 75HP Yanmar diesel Engines. The transmission is a Kazkaki KM4A ratio 2.14. the launches engines and transmission's are 2 years old. Due to shaking and vibrations in both engines in neutral and forward gears up to about 1500 rpm (no shaking in reverse) we replaced the transmission in one vessel and put aqua drives in both boats. we did not replace the transmission in the 2nd boat. Now this launch is exhibiting the same symtom. the other runs smooth. Are there known problems with these transmissions? Should we replace the 2nd transmission? Are they still under warranty after 2 years? any advice is appreciated.

04-18-2009, 11:09 AM
Vibration may be caused by a bent shaft/ prop or misalignment of the shaft to the gear coupling. This should be .004 thou. Contact Yanmar dealer ot Yanmar Marine service in Adairsville Georgia. Talk to them and get some expert opinion. These Kanzaki Gears are a good unit and rare to have problems.