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98 zx6r splitting the crankcase

Posted: Sat May 10, 2008 10:50 pm
by chikin
Pulling down my mates 98 ZX6R today and we have run into a little problem... Originally 2nd wont hold under any power and just pops out.

So he got himself a new gearset to go in and to do that you've got to rip the engine half apart.

So we tackled that mission today and dropped the engine out and took all the bits and pieces off, all the bolts out of the lower section of the crankcase but its stuck pretty damn well...

Is there any trick to getting it to split open? The shop manual says to tap lightly around the seam... that has made no difference, even giving it a good wack the the rubber mallet has done nothing :(

Re: 98 zx6r splitting the crankcase

Posted: Sat May 10, 2008 11:53 pm
by Rossi
Are you sure you have ALL of the bolts out ? It's easy to miss one :shock:
After that the cases are silicon sealed together and they can be a right cow to split.......try running a stanley knife blade around the seam before bashing it with the mallet ;)

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 10:40 am
by chikin
It is possible we have missed a bolt. We aren't flying totally blind and have a shop manual however the bolt positioning diagrams are so small they are almost useless.

Already tried a razor blade on 1 corner but its so hard to get it in to a decent distance between the surfaces we figured its never going to work.

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 5:18 pm
by Sulli
these may help

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 8:01 pm
by chikin
many thanks! :D

I suppose I really should ask... you can remove the lower half without taking the head off right?

All we want access to is the gearset.

I probably should clarify, 2nd pops back to neutral under acceleration, it stays engaged during 3rd to 2nd during deceleration leading him to believe its not the selector fork but rather the dogs on 2nd being worn.

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 8:22 pm
by robracer
Normally there is a pry point to help to split the cases with a screw driver but the idea that you have missed a bolt sounds about right :o

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 8:28 pm
by chikin
someone tell me so I know for sure... you do or don't need to remove the head from the upper crankcase to get at all the bolts to remove the lower crankcase?

It's not in the list of things to do in the shop manual we have... so I figured you didn't need to. Never done this before so I have no idea.

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 8:35 pm
by Rossi
No matey, the head stays on.
Apart from all the 10mm headed bolts, you have undone the main 12mm headed crank bolts ?
They're the one's that are giving me the shits at the minute, and am waiting for a delivery of a 12mm impact socket for my rattle gun :twisted:

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 8:43 pm
by chikin
I think so :P

I'll have to double check from the nice big diagrams.

There were 2 larger silver bolts that were a complete asshole to get out which I guess are the ones you are talking about.

If you are in the process can you tell me how many bolts all up should be out before the ass end can "fall" off? :P

I guess I may as well ask too if it is absolutely necessary to remove the clutch, the oil pump internals and the generator on the other side? You need magic tools to get those off which we don't have... thought it may still split open anyway.

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 9:04 pm
by Rossi
without running out to the garage..........
there was 30 ish of the smaller ones and
there's 10 of the bigger ones :twisted: ( of which - I can only get 2 to move)
As for removing the clutch, oil pump and generator........ well they are all connected to the drive shaft that you are going to be dismantling to get at the gears themselves, so it is probably easier to take them off now, rather than when you have the drive shaft out ;) , but the cases should split with them still on

At least this 1 is on the donor g/box, so with the exception of the clutch, it's already off.

Re: 98 zx6r splitting the crankcase

Posted: Sun May 11, 2008 10:25 pm
by chikin
Hrm I don't think we've taken out 40 bolts...

will have to have a closer inspection of these diagrams :)

Re: 98 zx6r splitting the crankcase

Posted: Thu May 15, 2008 6:30 pm
by Sulli
Theres closer to 50 bolts if you include the sump which I assume you have taken off :shock: to get to the main journal bolts :)

Re: 98 zx6r splitting the crankcase

Posted: Sat May 17, 2008 6:25 pm
by chikin
Oh right... the manual never mentioned anything about that :/ I wish someone had of said that earlier :(

Its too late now anyway... my mate hit it too hard near the edge with the rubber mallet and cracked the crankcase... so yeah anyone selling a zx6r engine? :P

It has been a decent learning experience and the bike was dirt cheap so he's not that pissed off. I did say we were probably too new to it all to try and tackle something like that with 0 experience without someone advising who did know what they were doing.

Re: 98 zx6r splitting the crankcase

Posted: Sat May 17, 2008 7:17 pm
by dave#3
chikin wrote:so yeah anyone selling a zx6r engine? :P
It's funny you say that .... I've got one from a 2000 zx6r that I moved today to my new place and went hhhmmmm, why do I still have this. It's about 50,000 km's old and was running until a problem with a fractured casting brought it undone. It's the engine mentioned in this thread. If you want it let me know - the price will be right ;)

Re: 98 zx6r splitting the crankcase

Posted: Sat May 17, 2008 7:58 pm
by TlTAN
a problem with a fractured casting brought it undone. It's the engine mentioned in this thread. If you want it let me know - the price will be right
would this fractured casting issue make the crankcase completely unusable? I only ask cos we already have a completely unusable crankcase :oops: