Well here is my carnage!

[trddunn]

Finally got my lower unit apart and here is a pic of the carnage! You can see that ALL the teath on the Fwd gear are gone! Some on the pinion gear are bad also. The reverse gear looks good. Also you can see the bearing on the drive shaft that went bad too. Does anyone know why this might happen? Age? I just changed the LU oil so it was clean. Thanks-Jason-

 

[14ftgrumman]

Re: Well here is my carnage!

Lack of lubrication? Shifter not fully engaged? Just plain worn out?

 

[robert graham]

Re: Well here is my carnage!

maybe your idle set way too high and hard on gears when engaged?

 

[kenmyfam]

Re: Well here is my carnage!

Does not look pretty. Replace the broken bits !!!!
You mention age ??? how old is the motor ??

 

[trddunn]

Re: Well here is my carnage!

I don't think it was lack of oil. I just changed it befor I went out. One thing I noticed was when I drained it after this happend it had pressure when I took the drain screw out. The motor is a 1988 48 SPL. It was going in and out of gear great to me? Thanks for you input guys

 

[bigskiohio]

Re: Well here is my carnage!

could have been lack of oil before, damage already done before oil change.

 

[petryshyn]

Re: Well here is my carnage!

is the pinion nut missing?

 

[R.Johnson]

Re: Well here is my carnage!

The photo does'nt show all of the pinion gear, but I would say the touble started there with the pinion and forward gear. It was possibly shimmed to tight, or hitting an obstruction, taking a chip out of these two gears'. Notice how hot it got. The driveshaft, and gears' are blue. I would certainly repace all bearing if I were to rebuild this case, if that is possible. Those broken, glass hard piece's went through everything.

 

[crxess]

Re: Well here is my carnage!

My first assumption would be bearing failure as the cause. Winter storage with old oil in the drive. Moisture develops in oil.(heat condensation) This could have lead to a stuck bearing. Once it popped loose a small portion may have dropped into the gears while running. That would snap off part of a gear tooth. From there it is only a matter of time until the gears rip themselves apart.

Unless someone has rebuilt the lower with replacement parts it is unlikely it was shimmed incorrectly.

 

[F_R]

Re: Well here is my carnage!

My wild guess is the bearing went first, probably due to lack of lubrication (low oil). Once that started breaking up and metal chunks dropped down into the rest, it all had to happen. As said, "guess". A chipped gear tooth could have started it all too.

I agree that the factory or any trained professional mechanic would have shimmed it right. Anybody else, well this is what you get.