Tri-z Separating Case

[sp1k3tou]

I bought a 250Z last year and now I need to rebuild it. I have been riding TRI-Z's all of my life and have never needed to pull the motor a part until now. I have the Yamaha manual but it doesn't say where I can get a case separator. I guess what I'm asking is how do you get the case to separate without the tool or where can I find one. I'm going to try and call a local yamaha dealer tomorrow.

Thanks

[kokmatt]

I didn't need one when i did mine. I just tapped all around on it with a rubber mallot until i got a utility knife between them then went all the way around. then carefully pried apart with a putty knife or small screw driver.

[tecat-z]

Harmonic balancer puller and some long metric 6mil bolts. Use wood shims to help the rear of the cases split at the same rate as front with puller. No metal contact and smooth as butter. They can be bought at auto zone, advanced, etc for small cash. It's the only way to do it without any damage.

[sblt500r]

rocky mountain sells them now. about $60 for the seperator

but you really don't need one. most old engines just fall apart!!!

[ATC-Eric]

If you CAREFULLY use a chisel, or a srewdriver, you can tap on the mounting areas. Theses are areas that do not have oil behind them, like where the cases meet the swingarm bolt.

If you want to do it properly, listen to Ed (tecate-Z).

[lndy650]

ive split many cases and never needed a seperater tool...but it would be good to have one in case it dosent want to come apart. if you use a screwdriver be very careful they crack really easy. and like ATC-Eric said try to tap on the engine mount areas

[sp1k3tou]

Thanks for the info. My one case is cracked where the kick starter is so I will be buying a new one from the dealer if they still have them. I'm going to try some of the thing that where said tonight and if it doesn't work I will go to autozone and rent there puller.

[sp1k3tou]

Ok it kinda helps when you remove all of the bolts that are coverd with dirt. woops. I removed the bolts and now the case is splitting but not coming a part all the way. I guess I will wait until I go and get the tool tomorrow.

[steven 250sx]

if its splitting it should be able to come apart just look closly to see what cud be catching it . keep wiggling and moving it around

[JohnBeton]

I always use a separator tool, I have one from Tusk. It was about 60$.
I also use it to drive out the crankshaft, drive out bearings, ... You can use it for a lot of stuff.

[sp1k3tou]

I posted an wanted ad in the sale section for the crank case 2. if anyone has one please let me know since all of the dealers I contacted today don't have anymore :(

[Dirtcrasher]

Most 2 strokes do need a case splitter. Some guys put the long bolts back in a few turns and lightly tap them evenly all the way around as a chinsey method of case splitting.

I've split plenty of cases and I don't have a tool for all of them so I make my own. A piece of flay bar 1/2 thick x 1.5" wide and you drill and tap a 1/2 - 13 hole in the center. Then drill 2 other holes that line up with some threads on the left case behind where the stator was mounted. Then you just need a piece of 1/2 - 13 threaded rod as the "pusher" that presses the crank away, and a couple of bolts to hold the bar into the case holes. Last one I made needed 2 long studs so I welded 2 8mm x 1.25 bolts together, threaded them in the case, slid the bar over them and put a nut on top. I think that was for a Blaster.

It can be made for nothing if you have taps, drills and metal kicking around or just a few bucks if you have to source them.

Hope that made sense......

[sp1k3tou]

I got it a part using wood shims. Both cases are shot. The only thing that is good is the gears and I'm not sure if my crank is bent. This all happened because I had the cylinder bored to the max and some on was sitting on my bike while it was in gear and it rolled backwards and cracked the bottom skirt of the cylinder sleeve which then got stuck in the crank. I didn't know any damage was done until I tried to lick start it and the crank locked up.

[Dirtcrasher]

I got it a part using wood shims. Both cases are shot. The only thing that is good is the gears and I'm not sure if my crank is bent. This all happened because I had the cylinder bored to the max and some on was sitting on my bike while it was in gear and it rolled backwards and cracked the bottom skirt of the cylinder sleeve which then got stuck in the crank. I didn't know any damage was done until I tried to lick start it and the crank locked up.

I'm confused....

Was the engine APART and someone sat on it, rolled it backwards in gear which allowed the piston to rock and get caught on the lower case, or did something else happen?

If so, I'd choke my stupid friend............ :lol:

[sp1k3tou]

The bike was on top of the hill in gear and a friend sat on it. It then rolled a little backwards and I think the piston angel put to much stress on the cylinder sleeve at the bottom and the ears broke off and when I started it up not knowing it ground up and got stuck under the crank when I turned it off. Then when I went to kick it again, the motor felt like it was seized.

[Dirtcrasher]

So this was a running motor and someone simply rolled it backwards a bit and you think that damaged the piston??:crazy: I think your nuts..... You owe your friend an apology, :lol:

[lndy650]

most likely the skirt was already cracked or brittle and it just happened to break when you started it after he sat on it...the engine turning over backwards cant hurt anything

[kokmatt]

I have a left side crank case laying around if your still looking for them.

[sp1k3tou]

Yes it was a running bike and I didn't say anything to my friend about it so no apology is needed. I think the machine shop that did the bore on the cylinder might have caused it since they do mostly car engines and I just had that cylinder bored there. The thing that sucked is I fixed my carb problem and the bike was rocking right before that happened. But I have another 85 tri-z to ride which is stock and has never been rebuilt that my uncle has owned since it was new so I was able to play before winter hit.