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1986 honda cr 250r tranny oil blowing out bad from exhaust help

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the bike runs good when it runs..but its blowing oil out everywhere really... at the exhaust where it goes into the cylinder clear out of the back..and when i say bad i mean real bad..it smokes like a freight train and oil just drips all over the swingarm and out the exhast..my question is..is it the right side clutch side crank seal?   thanks alot guys  Rob* p.s i just threw in a pic of my bike

1383396_395068987289460_501120341_n.jpg

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if you've got transmission oil in your crankcase, then yep, you got blown seals....split em and replace.  Almost as easy said as done.

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if you've got transmission oil in your crankcase, then yep, you got blown seals....split em and replace.  Almost as easy said as done.

 

if you've got transmission oil in your crankcase, then yep, you got blown seals....split em and replace.  Almost as easy said as done.

do i have to split the case?

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No you don't have to split the cases to change the crank seals. Before you get to deep into first go over a couple things. First thing is what is your jetting set at? Oil mix ratio and type of oil? Leak at the exhaust flange. If your jetting is good and your airfilter is clean then do a transmission oil change and measure out how much you put in. Drain the oil again after running the bike into a measuring cup (ratio rite) and see if your losing oil. If you just did an oil change recently and you measured it out like you should have then just simply drain it and see what you have. If your losing oil then your right side crank seal is bad.

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I am on my mobil phone..but i bought a new main jet for my carb so i dont know what you mean by jetting..the bike runs it just blows oil from the bottom end out of the pipe..its not two sroke oil..i am using 2 stroke oil in it i mix it .4 ounces to 1 gallon .. so how could a carb jet suck oil into the top end from the tranny and blow it out of the exhast? And i mean pour it out...strange..and why would the air filter or carb even have anything to do with tranny oil getting into the top end out of the exhast on the cylinder? Ty for the help

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no reason for a leak down test..its leaking for sure i would say..if you have oil blowing out of the exhast the seals would have to be the reason right? what else could cause oil to get into your cylinder exhaust manifold?

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You asked a bunch of guys sitting behind computer screens if your bike is sucking tranny fluid through the rightside crank seal.... when I say do you a leak test you tell me there is no reason to. :banghead:

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You asked a bunch of guys sitting behind computer screens if your bike is sucking tranny fluid through the rightside crank seal.... when I say do you a leak test you tell me there is no reason to. :banghead:

 

You asked a bunch of guys sitting behind computer screens if your bike is sucking tranny fluid through the rightside crank seal.... when I say do you a leak test you tell me there is no reason to. :banghead:

lol  i understand what you are saying..but i know that it is blowing a sh*t load of oil out of my exhaust,,, what is a leak down test going to do for me?  if its leaking anywhere other than the crank seal it shouldnt suck oil up into the cylinder should it? or could it?  i wish i had a video for you..put it this way..my dad has a fence at his house and i fired it up and let it run for about 20 mins or so and there is oil blown all over it,,,all i am saying is other than the crank seal is there really something else that could make oil blow out of the exhaust from the tranny? just sayin..and it is so freaking frustrating..it also boggs down when i idle it up..and i get tranny oil on my spark plug and then have to clean my plug and try to run it again..almost like it floods the plug litterally with tranny oil   ,,, i feel like doing :banghead: myself lol

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are you sure it's tranny oil?   you can have tons of pipe spooge and drool just from the premix

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That is a lot of prenix at 4 ounces to a gallon. What type of premix oil are you using ? Is this bike all stock or are there modifications done to the bike ? Pipe, porting? Reeds ? Head mod?. What type of riding do you do and your skill level at riding ?

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listen guys,,,,i put 4 ounces of oil in 1 gallon of gas okay? it blew out 5 times that i would say...i am talking a shit load of oil was all over the place..dripping everywhere out of the exhast.. its even getting on the plug...it is 100 percent for sure trans oil

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its a 86 with a 89 cylinder on it.. the piston is the right size so is the rod everything is the correct size..and my mixture of gas is 4 ounces of 2 stroke oil to one gallon of gas... some how oil is getting into the cylinder and blowing it out of the exhast...i can't think of any other way that could possibly happend...unless mabey the rings..but there is great compression so i wouldnt think the rings would be the problem..not with that much oil blowing out...now at first i thought mabey i put in to much trans oil...but i drained it out and now i cant get it to run..i gave up for the day..so tommaro i am going after the seal and possibly going to putt the cylinder and make sure my rings are good

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if you seen the oil coming out of the pipe you would think how in the hell is oil getting there like that..and it wasnt like it quit doing it after running it for a while..it kept on spitting it out

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4 oz per gallon is 32:1 mixture, perfectly fine for that motor. It is most definitely the right crank seal. Pull off the side cover, take off the crank gear and the seal is right there. Super easy to replace.

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No i am just hoping i am right and asking for advise and hoping no one tells me its something other than a seal cause i never even heard of this happning...ty i will go after the seal first..if any other advice. Its much appreciated. Thanks fellas..wish me luck

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I don't understand why you feel the need to argue with people who are trying to help. Ok so your mixing your gas at a 32:1 ratio, that's fine. The reason I asked about your jetting is because believe it or not jetting causes spooge. If you KNOW for sure its trans oil then yes your crank seal is bad. Your jetting is obviously not right though if the bike is bogging and everything else. If you tell us your current jetting we can tell you if its anywhere close to where it should be. I realize you a complete genious since you point that out to everyone on every other post, but apparently you lack common sense. Changing a crank seal if that's not the issue is not going to fix your problem. And honestly we all know that you put an 89 cylinder on an 86 bottom end and that the schematics say this and you changed the powervalve part and blah blah blah. You do not need to keep posting that twice a day. We know and we do not care.

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I don't understand why you feel the need to argue with people who are trying to help. Ok so your mixing your gas at a 32:1 ratio, that's fine. The reason I asked about your jetting is because believe it or not jetting causes spooge. If you KNOW for sure its trans oil then yes your crank seal is bad. Your jetting is obviously not right though if the bike is bogging and everything else. If you tell us your current jetting we can tell you if its anywhere close to where it should be. I realize you a complete genious since you point that out to everyone on every other post, but apparently you lack common sense. Changing a crank seal if that's not the issue is not going to fix your problem. And honestly we all know that you put an 89 cylinder on an 86 bottom end and that the schematics say this and you changed the powervalve part and blah blah blah. You do not need to keep posting that twice a day. We know and we do not care.

i am not arguing at all..i took it apart today and the clutch side crank seal was half way seated...if the rings go completly out or the carborator is completly wrong there is no possible way the tranny fluid  gear oil in the clutch can make it into the exhast unless its a bad seal....i tore it down today and found out it was  a seal half seated.. no agrguement..fuel mixture jetting or none of that can cause tranny gear oil to get into a 2 stroke top end unless the seal is bad..is all i am saying..and i found it out today.... it seams to me the same people commenting doubtfull things are either lacking commen sence themself or just young kids who think they know it all..one more time...there is no way possible tranny gear oil can get into your cylinder unless the crank seal is bad on the right side..right that down so you will know when ur common sence dont kick in and it hapens to you

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