Tri-z Piston Failure

[Just-Tri-It]

Can you go to this page of diagrams and give the one you are referring to. Thanks


http://www.boats.net/parts/search/Ya...I-Z/parts.html

[Mosh]

Gear #8 in this diagram. It can fall right off the shaft. There is no retainer clip. So pay attention to it.

http://www.boats.net/parts/search/Ya...ION/parts.html

[Just-Tri-It]

I noticed on the inside of a spare case I have that there is a set of needle bearings right next to the clutch push lever assembly. Is number 10 that bearing the the same shaft carrying the number 8 gear rides on? The bearing has lost a couple needles in it and if the other one is like that I will need to replace that bearing as well.
Thanks

[jmax857]

Gear #8 in this diagram. It can fall right off the shaft. There is no retainer clip. So pay attention to it.

http://www.boats.net/parts/search/Ya...ION/parts.html

when you put it in backwards, the transmission wont spin freely when the cases are "mated" together. i did this when rebuilding mine, i put the halves together and the tranny wouldnt move. i had to split it again and swap that gear around. its pretty obvious if you did it wrong.

[Mosh]

I noticed on the inside of a spare case I have that there is a set of needle bearings right next to the clutch push lever assembly. Is number 10 that bearing the the same shaft carrying the number 8 gear rides on? The bearing has lost a couple needles in it and if the other one is like that I will need to replace that bearing as well.
Thanks

Yes that is correct. Number 10 is the input shaft main bearing.

when you put it in backwards, the transmission wont spin freely when the cases are "mated" together. i did this when rebuilding mine, i put the halves together and the tranny wouldnt move. i had to split it again and swap that gear around. its pretty obvious if you did it wrong.

Exactly. That is why I mentioned this issue. A) Guys will let it run that way. I actually took a Z engine apart that toasted that thrust washer and bearing becuase they ran it wrong.
B) Having to resplit a case after you have all the bolts in and a new layer of Yamabond on them sucks. So now, it can be done right the first time.

That #8 gear has a bevel on one side and a flush side with no bevel.That is why you want to pay attention to it when you split the case. The manual does NOT dictate which way it goes.
You should be splitting the case from the stator side (Left case coming up off the right case), so the gear should remain oriented in its correct location since the trans shaft will stay in the right side case as you pull the left case.

[Just-Tri-It]

No. But here is a link to a good video series I posted, that used with the Z manual should walk you right through the process. It is a newer Yz 250 engine, but all steps are about the same.

NOTE!!! On a Z engine, the Input shaft end gear on the left side of the case (by the clutch arm) can be installed eiter way. One way is right, the other is wrong. Pay VERY close attention to the gear as you split the case and keep it oriented in its correct posistion


http://www.3wheelerworld.com/showthr...ed.&highlight=

Is the video in the World Class help section?
Thanks

[Mosh]

Is the video in the World Class help section?
Thanks

Click here.
http://www.3wheelerworld.com/showthr...ed.&highlight=


There is 3 parts I posted in order. In that thread^^^
Click each youtube vid to see them.
I did not make the vids. I only posted them here.