Crank bearing replacement

[mutany15]

I just got done doing all this and it was a major pain.... If I had to do it all over again and had nowhere to take it, I would buy a used motor off ebay or buy all the tools, seriously... and I work at a automotive machine shop so Im no dunce with tools. On the other hand, Im all for tinkering, you learn alot of sh*t doing it the hard way. Anyway here are some things to think about that may not be so obvious until you try start trying to get it apart.

As regal said the cases are glued together and using a screwdriver to pry them apart will (the aluminum is just so soft) damage the cases so that when you put it back together it could leak oil. Not only are they glued, but the balancer, crank main axle and drive axle are pressed into the bearings, pretty much llocking the case halves in place. You will almost defintaley need a crank holder in order to get the bolt off the right side of the crank, i doubt an impact gun will take it off. Pressing it back together can be difficult. If your dad has a machine shop it will be much easier, but those shafts arent going into the bearing unless you have a press. If you are half assing it you are inevitably going to screw up a few oils seals so I'd recommend getting an oil seal kit also. Also, the shift cam/shaft doesnt cooperate staying in place when you are putting it back together.

BTW, Blaster bottom ends having been selling on ebay for $200-$250. I bought one Monday for $197.

 

[89custom]

Got the new crank and main bearing/seals and hopefully the gasket kit and piston will be in by friday.

if i get to a point were i know its going to be sh*ty geting it back together without the puller, ill just get one. for now, im not going to use it.

 

[89custom]

So im geting into it today. is there anything specific i need to know? (like does it have to be in a specific gear before i take gears off?) stuff like that i need to know. the little stuff that can save me a spring flying across the garage and losing it. ive got the clutch cover off and all the oil out so the clutch is infront of me. now do i have to take the clutch apart piece by piece or can i take the whole assembly out, with all the plates as a whole instead of making it complicated. its just something else i can mess up, i wana eliminate losing the order of how it goes together.

oh and does anyone know of a video or a step by step with pictures help with how to fully take it apart? specifically a blaster. i found 1 thats very similar but i want a blaster one just so i can see everything with no supprises.

 

[mutany15]

It doesn't need to be in gear or anything, One thing to keep an eye on though once your in there is a long metal rod that goes into one of the shafts, on the other end of that rod is a small round steel ball, almost the size of a BB. Just watch that the rod doesnt fall out with the steel ball behind it, its very easy to loose.

You may be able to get away with leaving the clutch on it. I can't remember if the manual specifies to take it off. I didn't take the clutch off when i removed the crank. However, the clutch is pretty straight forward to take off. You can get around not taking each individual plate off, but you will have to unfasten all the bolts (6 total, 5 with springs and the one in the middle) from the top peice, once those are off you can see where it is bolted onto one of the shafts (I believe it is the main axle). You will see that the bolt is held in place by a bent peice of metal, its easy to flatten back out with a screw driver. The clutch is pressed onto that shaft and now that i think about it you maybe be able to take it off with the flywheel puller. I didn't even think to use that at the time, i just pried it off.

 

[89custom]

It doesn't need to be in gear or anything, One thing to keep an eye on though once your in there is a long metal rod that goes into one of the shafts, on the other end of that rod is a small round steel ball, almost the size of a BB. Just watch that the rod doesnt fall out with the steel ball behind it, its very easy to loose.

thats such a coincidence because i was looking at the new manual i just got and noticed the little ball and just made sure i remebered to get that ball without losing it.

going to take off the clutch and all the gears in the clutch cover side tonight. going to take lots of pictures so i remeber how it all goes back together.

 

[89custom]

OK WHAT THE HELL. im stuck. i took the kick start assembly off and the the clutch plates are all out. ive bent back the washer that keeps the bolt on the main clutch center from untightening but i have no idea how to get that bolt off. its on a spinning part and theres nothing to stop it from moving. i was going to jam something in there to stop it from moving but i dont want to damage or warp anything so im stuck.

i need someone to explain how to lock this thing up so i can get that nut undone. im trying to do everything myself on this job(no help from my dad) but for this one, i know if i get him to do it, he will jam something in their and wreck something.

 

[mutany15]

Ok, there are a few solutions. I had to remove my clutch this afternoon to put it on a different bottom end. Here is what I did. You see all the gears on the end of that shaft, on the other side of the case. I put that last gear (the little one at the end) in a vice and untightened the bolt. It may sound like a bad idea, but it actually didn't damage the gear. I'll post some pictures if you think it will help any. They are hardened steel gears so as long as you don't really crank the vice down, they will hold. I was using a 24" breaker bar to get it off and it came off with minimal effort.

If you don't have the cases cracked and dont have access to the tranny, you could put the chain on the sprocket and step on it to keep it from moving, or somehow try to lock the sprocket in place in order to lock up the transmission in order to get that bolt off.

 

[mutany15]

Oh and btw, that clutch basket is super brittle. it will crack if you put stress on it.

 

[89custom]

thanks for the brittle tip thats really good to know. and i didnt even notice the sproket for the chain was turning with that lol. i guess i was just geting pissed off and didnt think a bit WHY it was turning freely lol. k know i know what to do. thanks a ton.

 

[geteminline]

keep us posted how this is going!!!!

 

[89custom]

ok well i got the bolt off, i just put some vice grips on the shaft were the sproket goes and got it turned off BUT i messed up the lock washer. the tab holding it from spinning ripped off because it spud with the nut when i was taking it off. is it important or can i leave it? i would have to order one and it will take awhile. can i do without the tab keeping it from spinning? like thats the whole point of it but i dont see how its going to come undon anyway.

and ive got 2 case screws that are in there so tight i can get them out with a normal screwdriver. im going to go pick up a impact screwdriver from canadian tire today that should get them out then i can start spliting it.

seems to get easier and easier. i found out i can use my dads arbour press at his machine shop for geting the crank in and out if i really need to. if i can do it with a mallet and some elbo grease then id be happy.

also going to pick up some threebond from candy tire too and anything else i might need.

 

[regal81455]

little tip for ya, you can use a penny and wedge it in between the gears when loosening and tightening things that will otherwise spin if you do not have the "proper" tools for those jobs as well. i do not know for sure if you can press the crank in place, your really suppose to be pulling it into place but if your dad's a machinist and he thinks it will work by all means try and GL.

 

[mutany15]

Where did the locking washer get screwed up? was it where it locks to the basket, or to the nut? because if it was at the nut then it looks like there is another tab you can bend up.

I don't know how vital that lock washer is but remember that nut and washer hold on the clutch on. If that nut starts loosening, you might start loosing your clutch or it may start slipping, to the point that it doesnt even engage possibly. However... maybe some Loc-tight red will do it. At least put something on it if you opt not to use the washer.

Personally, I would order and wait for the lock washer

 

[89custom]

k i might get a new washer.

but right now ive goten pretty far. this seems like a 1 day job, if you got all the tools. but not for us. we went to my dads machine shop and used his arbour press to press out the old crank out of the one side. other side just tapped out. the bearings did go with the crank but we dont care because were not using that crank, if anything its better.

the problem now is we do need a crank puller/installer tool because theres really no other way. were going to talk to our local shop and see if there nice enough to just install the crank. or let us borrow a tool for the day or something. were almost done. oh we did have a misshap with the transmision lol. tapping at something, i forget, but the sh*t all slid out of place, 1 shift fork came off and i flipped out. eventually we got it all back in where its supposed to go and its all good but i thought it was going to be worse.

soooo regal, you can slap me now. i need a crank puller/install unless you got any other ideas. you cant press the crank in it will ruin the crank so its gota be pulled in somehow. oh we did "sweat" the bearings in. worked well for just a freezer for an hour and a oxy acetalyn torch that we had at the shop. they fell right in nicely.

almost done! oh, need to wait on gasket kit, backordered from one company till late august! so we found another supplier.

 

[89custom]

is this the tool i need to install the crank. im am geting pissed off because i dont know what i need exactly. i have the old crank and old bearings/seals out and new bearings and seals in with the case halfs split ready to put back together with a crank. my problem is i cant use a arbour press to push the crank in, its gota be pulled it, so i know i need a tool. BUTTTTT do i need a splitter from this point? or is the splitter ONLY to take the case apart? like i need to confirm that i DONT need a splitter also. i know i need the puller installer, and i can live with that.

ATV Parts, ATV Tires, Dirt Bike Parts & Motocross Gear - Tusk Crank Puller/Installer Tool | Rocky Mountain ATV/MC

 

[regal81455]

yeah, you only need the puller now, the case splitter is exactly that, its splits the cases. don't forget the yamabond 4, you can order it from rocky mountain at the same time...

 

[89custom]

UPDATE!! (happy update )

i was geting impatient so me and my dad rigged up a little contraption to pull the crank in. it worked! we just used spreaders and risers, tighting the nut then adding more spacers and tightening it some more. worked great.

sucess!

the only thing now is the clutch thats confusing me. first of all i have to figure out how the push rod goes, cuz theres that strange end on it with the 2 bolts and screw spot. w/e ill get that eventually, but if anyone can just help me out with that that would be great.

also, another stupid clutch problem, this picture was from before i took it apart.

notice the red circled area. the plate with the thing washer type thing was close to the inside, when in the manul i got says it should be on the outside, 2nd friction plate in. either im wrong or the guy before me did it wrong. what is it?

 

[regal81455]

one of the clutch plates inner diameter is different from all the rest so find this plate first and set it aside, the order goes regular clutch plate, friction plate, odd clutch plate, clutch spring ( large washer thing ) then friction plate, and then its clutch plate, friction plate, clutch plate till you run out...

 

[89custom]

ok i got that.

now my problem is this all show no sh*t shop thats near us. yeah there all f*cking fancy but jesus christ they are the wosrt shop ever. nothing but bullshit from them and now, i find out they gave me the wrong f*cking piston. its to small. it slops around in the cylinder theres no way its right. and the idiot honed it and took a measurement. what a f*cking joke. im tired of all this bullshit there all greedy companys that dont give a sh*t about the customers unless there giving them money, in our case, we didnt pay them to do this so they dont give a sh*t if we have to wait a year for the right f*cking parts.

i hope any of you guys on here with shops arent this way.

 

[regal81455]

sorry to hear that...