Ive got a 70hp yamaha autolube and everytime i try to put it in reverse all i get is the crunching sound like when your between gears all the way through reverse and then every now and then it will go in smoothly and perfectly. It will also go in perfectly after a long fast run of the engine.
check the tickover speed isnt too high and try changing the gearbox oil. check theres no water in there.
may help. also worth oiling all the linkages and checking everythings free.
if its none of the above you may need to take it to a tech.
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I am usually not as green as i am cabbage looking.
Jizm I can 99.9999999% sure I know this problem . Look under the bottom carb and you should see a detent SPRING held on by a 10mm bolt . If this DETENT plate is NOT there then what happens is when you try engage reverse the shift shaft is moving all over the place and you WILL NOT get a positive engagment when the clutch dog in the gearbox tries to engage into the reverse gear and you will hear the GRRRRRRRRRRRRRRRRRRRRRRRR etc . If this problem is NOT solved you will wear out the teeth on the clutch dog and on the reverse gear . And what happens when you go into foward there is NO force on the shaft what so ever . check that out first before you start pulling gearboxes apart . I have had several of these out there . baz
