engine problem

looks like i popped a seal on the crank and oil is getting out on the stator.How much can i expect to spend to get this fixed.Its a 91 kx500.I'm new to the site and would appreciate the help or some insite as to if this is a major fix.


As far as repairs go, it is one of the more complicated ones. The crankcase halves must be seperated. Search around for no1clyde , and his post on work inside the engine.

this is one reason WHY i dislike kx`s 250 and up mx bikes.


Many of the Kawasaki's require the crankcase halves to be split to replace the main bearing seals. What would your dislike have to with the size??

i dont like the cranks seals internally that you need to split the cases. if KXs designers would redesign the motor for external, id be all over green by now.

whats the benefit of having the seals internal anyway?

OK, you are opposed to the internal seal design. I am not sure on the design benefits.

Apparently, the designers thought you could blow out the seals...or maybe it was to get you to replace the bearings and seals as a pair, instead of just throwing in seals.

It's not THAT big of a deal...it's not like you have to replace them every 6 months. lol My 05 still has not been split.

i know but sometimes seals just fails unexpectedly. same as if i were to install a new ones and thought, with all the effort, that iv been doing a great job. then yiu get a seal leak from the first start. all this will cost new gasket, cleaning and time when you should be riding instead.

this is one reason WHY i dislike kx`s 250 and up mx bikes.

yup. ill never buy one for this simple reason. what kind of jackass would make a design like that :thumbsup:

In my experience, the main reason for crank seals leaking is bad main bearings. I dunno what kind of fella puts in new seals without replacing the bearings anyway, so access from the outside seems pointless to me. Probably what kawi had in mind with the design as well. Maybe the figured they'd save some people from catastrauphic failure if they had to split the cases when they should have, instead of just throwing new seals in from the outside and calling it good.

i know but sometimes seals just fails unexpectedly. same as if i were to install a new ones and thought, with all the effort, that iv been doing a great job. then yiu get a seal leak from the first start.

Cuz...I worked in a truck shop for 10 years, been working on my small fleet of delivery vehicles for 11+ years (not to mention the bikes I worked on) and never put a new seal in and it started to leak prematurely. If that happens then you missed what caused the seal to leak in the first place which was most likely a worn shaft or bad bearing, etc. SO...you would have to split the cases ANYWAY! :thumbsup:

well, you can always call me lazy:) i love green but with the seals, i aint getting one.

How often do you think you are going to have to replace seals, then??

Would most anyone not NEED to replace the bearings as well??

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