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Crankcase Implosion!!!

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  #11  
Old 11-13-2010, 04:36 PM
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Originally Posted by e3gordon
Thanks what kind of epoxy is suitable to glue back?
JB Weld should work
 
  #12  
Old 11-13-2010, 07:34 PM
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+1 - JB weld
 
  #13  
Old 11-15-2010, 02:08 PM
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Just a theory, but if the bike was warmed up, so that the oil was nice and warm (idk how hot the oil will get). If, while the oil was still really hot, you opened the crankcase to add oil or w/e reason; the hot and pressurized air would have escaped bringing the pressure down to atmospheric pressure (14.7 psi). If you then closed it back up while it was still hot, there would be far less air in the crankcase. You then get a very cold night and because there is not much air mass in there the pressure will start to drop inside. This would put a force on that window pushing inside the crankcase.

Now there is a ton of "ifs" and whatnot in this scenario, and idk if the oil even gets hot enough to create such a force in the end. If it was a complete vacuum inside the crankcase it would only be about a 15 pound force pushing on that window, that might not even be enough.

Again, this probably didn't happen, but thats just what came to mind when I read the word implosion.
 
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Old 11-15-2010, 03:38 PM
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this happend to my ninja 250 when i dropped it a while back. Acually the sight glass broke because my rear brake smashed it. I bought a new sight glass for about 12 dollars. I had to carefully brake the rest of the glass and pull out small pieces to make sure shards didnt get into my engine. To replace the sight glass i popped it off with a screw driver, the other sight glass is held in place with that black rubber ring, i got it in by pushing it with my finger, and than using a rubber mallet to get it flat.

On the ninja 250 there was nothing keeping the glass attached to the case, but only the rubber. It fit really snug. I dont think you can just pry it out because the cbr looks alittle different, maybe you have to take off that engine cover and push it back. Or order in a new part, it should not cost that much.. idk

I dont know if I would use jb weld, im always afraid of little shards getting in the engine, well it depends what you think. isnt that window surrounded in rubber?
 
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Old 11-15-2010, 06:25 PM
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Agreed with gotpepsi. I would be afraid of a chunk of jb weld getting inside the motor and really causing a issue. I think jb weld is a great cold weld outside the motor but inside its to risky for me. Personally I would buy a new one. Otherwise take it off and check it out on how its holded in.
 
  #16  
Old 11-15-2010, 06:39 PM
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Originally Posted by Krux
Agreed with gotpepsi. I would be afraid of a chunk of jb weld getting inside the motor and really causing a issue. I think jb weld is a great cold weld outside the motor but inside its to risky for me. Personally I would buy a new one. Otherwise take it off and check it out on how its holded in.
Yeah I was worried about the same thing....not sure if anyone knows how the window is adhered to the inside the crankcase....feel free to weigh in if so. This is weird problem to have!
 
  #17  
Old 11-15-2010, 07:32 PM
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After doing a bit of research i found out that Honda does not have a part number for their sight glass, so if you break the glass your **** outta luck and you have to get a new engine cover. I do not believe that the sight glass is being held to the case by any type of glue or sealant. If you want to fix that right you can just get a new engine cover and call it a day. however i did find a few threads where people would take off the sight glass to get the engine cover powder coated.

http://www.fireblades.org/forums/too...s-removal.html
According to fireblades.org "I bought a used cover and stripped it to repaint. The sight glass is encased in rubber. I removed it with a little leverage on the metal cage and it came right out. Its the same as pressing in/out a bearing. Pull it out evenly from both sides. Wiggle a little on this side, wiggle a little on that side and so on. It came out surprisingly easy."

The sight glass is encased in rubber. It seals its self against the engine cover by fitting snuggly agains the case.

http://faq.ninja250.org/wiki/How_do_...sight_glass%3F
I did this with my ninja 250, the only difference is that kawi has a replacement sight glass. I used no sealant, the rubber is just a snug fit. No leaks. instead of putting the glass in the freezer, i just dipped it in oil and pressed it in there with my finger.
 
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Old 11-15-2010, 08:14 PM
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Great job Gotpepsi!

Originally Posted by Gotpepsi
After doing a bit of research i found out that Honda does not have a part number for their sight glass, so if you break the glass your **** outta luck and you have to get a new engine cover. I do not believe that the sight glass is being held to the case by any type of glue or sealant. If you want to fix that right you can just get a new engine cover and call it a day. however i did find a few threads where people would take off the sight glass to get the engine cover powder coated.

http://www.fireblades.org/forums/too...s-removal.html
According to fireblades.org "I bought a used cover and stripped it to repaint. The sight glass is encased in rubber. I removed it with a little leverage on the metal cage and it came right out. Its the same as pressing in/out a bearing. Pull it out evenly from both sides. Wiggle a little on this side, wiggle a little on that side and so on. It came out surprisingly easy."

The sight glass is encased in rubber. It seals its self against the engine cover by fitting snuggly agains the case.

http://faq.ninja250.org/wiki/How_do_...sight_glass%3F
I did this with my ninja 250, the only difference is that kawi has a replacement sight glass. I used no sealant, the rubber is just a snug fit. No leaks. instead of putting the glass in the freezer, i just dipped it in oil and pressed it in there with my finger.
 
  #19  
Old 11-15-2010, 08:55 PM
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Originally Posted by Krux
Great job Gotpepsi!
definitely thanks for the input and background research!!!

Still open to suggestions but once i get the case off I will take some photos and update everyone as to what I find, meaning how the window is held into place and all that...
 
  #20  
Old 11-15-2010, 09:27 PM
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Permatex makes a product call "right stuff". It's a gasket maker/o-ring in a can/ radiator fixer/ fuel leak fixer (or sending unit glue). The stuff holds up to any chemicals I've tried it with (anything automotive related) and it a great fix in a pinch. It's also a great fix for certain things. I would recommend it for this just so you know for sure it re seals. The old rubber gasket on the sight glass might not cut it by itself anymore but if you smear a little of this stuff around it you have my personal gaurentee that not only will it not leak, it will stay! (just make sure the surfaces are clean!
 


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