I just completed the break-in ride on the rebuilt motor in my 98 KX250. Jim with 2Fast did the bottom end while Eric treated the top end to his 2mm over magic. As you would expect, the motor rocks. To give you a feel for the time on the motor, I burned a full tank of gas during this first ride. The gearbox fluid, (type F ATF) turned a very dark purple during this one ride. I've always run type F ATF in this bike and have never had it turn this color; even in 3 or 4 rides, my normal change interval. My guess/hope is that this is normal in that some sort of rebuilt residue gets flushed out with the first oil change. Any comments would be appreciated. I'm not a clutch abuser. This is the original clutch in the motor and Jim said it looked fine upon tear down. Thanks in advance for your comments.
Funky looking gearbox fluid after break in
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jmics19067
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one guess would be the atf mixing with whatever assembley lube he used in the gear box?
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Update. I spoke with Jim w/2-Fast and he told me to change the fluid and go for another ride. I did so and the motor again ran well, and I didn’t detect any clutch slippage, I think? But the bottom line is the gearbox fluid became very discolored again, dark purple, after only burning about ½ tank of gas. It’s never fouled up the oil like this before, even after several rides, so I know something different is going on. So I called Jim back again and he told me to check several things.
1. Pull the spark plug to see if it is oil fouled. If yes, this could indicate that the crank seal is leaking and letting gearbox fluid into the combustion chamber. Apparently when this happens, some combustion chamber mixture can also be pumped back into the gearbox, which could be causing the discolorization. I pulled the plug and it looked normal. A little on the rich side but not wet at all. This fact combined with the fact that the motor runs well, does not spooge and does not smoke hopefully rules out the crank seal as a problem. Furthermore, the gearbox fluid level appears to be remaining constant. It could be dropping just a tad but I don’t think so.
2. Check the radiator fluid level for dropping. Coolant level is remaining full. No issues here.
3. Pull the clutch and look for signs of burning. I pulled it, and visually it looked OK. The fibers were very hard in that I could not scratch them with my fingernail. Possibly they are glazed over. I then took out my vernier caliper and measured the plates and springs against Kawasaki specified service limits. All the plates, fiber and metal, were under service limits. The springs were above service limits but just barely.
I called Jim back and we agreed that the best play for now is to replace the clutch. After all, it needs replacing anyway. I ordered OEM fibers, metals and springs, $166, and will install when they arrive in a few days. I really hope this is the problem in that this is an easy fix. It is the original clutch on a 98-model bike. The only thing that bothers me is that I really don’t think I can feel the clutch slipping, and my fluid never fouled up like this before the rebuild. Maybe the fact that the clutch is beyond service limits combined with the power of the new motor was enough to take the clutch over the edge.
I’d appreciate any feedback on this scenario.
Worthy of noting, Jim has been extremely receptive to my questions and has stated that he will be more than happy to fix anything that may have been related to his rebuild.
1. Pull the spark plug to see if it is oil fouled. If yes, this could indicate that the crank seal is leaking and letting gearbox fluid into the combustion chamber. Apparently when this happens, some combustion chamber mixture can also be pumped back into the gearbox, which could be causing the discolorization. I pulled the plug and it looked normal. A little on the rich side but not wet at all. This fact combined with the fact that the motor runs well, does not spooge and does not smoke hopefully rules out the crank seal as a problem. Furthermore, the gearbox fluid level appears to be remaining constant. It could be dropping just a tad but I don’t think so.
2. Check the radiator fluid level for dropping. Coolant level is remaining full. No issues here.
3. Pull the clutch and look for signs of burning. I pulled it, and visually it looked OK. The fibers were very hard in that I could not scratch them with my fingernail. Possibly they are glazed over. I then took out my vernier caliper and measured the plates and springs against Kawasaki specified service limits. All the plates, fiber and metal, were under service limits. The springs were above service limits but just barely.
I called Jim back and we agreed that the best play for now is to replace the clutch. After all, it needs replacing anyway. I ordered OEM fibers, metals and springs, $166, and will install when they arrive in a few days. I really hope this is the problem in that this is an easy fix. It is the original clutch on a 98-model bike. The only thing that bothers me is that I really don’t think I can feel the clutch slipping, and my fluid never fouled up like this before the rebuild. Maybe the fact that the clutch is beyond service limits combined with the power of the new motor was enough to take the clutch over the edge.
I’d appreciate any feedback on this scenario.
Worthy of noting, Jim has been extremely receptive to my questions and has stated that he will be more than happy to fix anything that may have been related to his rebuild.
marcusgunby
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MXTEX i think you are spot on with your thinking-a new top end and a worn clutch is a bad combination.
Is the rebuilt motor, with extra power, putting more stress on the bottom end? Maybe this is making the oil change colors quicker.
One other idea...maybe it was doing this all along. I know I watch things (and listen) to things much closer after I have worked on them.
One other idea...maybe it was doing this all along. I know I watch things (and listen) to things much closer after I have worked on them.
Peer Lovell
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- Nov 25, 1999
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I agree with Rcannon. It's normal for the transmission fluid to change color very quickly. Maybe it always did this and you are just noticing now?
I really hope that WE dont have one.I just had the top and bottom rebuilt.
seals,crank,bearings,133 kit. Its an 01YZ125(well,it use to be :confused: )
Fluids are good.Never use to turn purple before.
Did one oil change after break-in last week and will do it again today.
I have the bike jetted on the rich side but haven't oil fouled the plug yet.
Smokes alot due to not jetted right,but will lean it out today.
Gotta get it dialed in for my kids winter racing.
and I wanna race his bike too,
in the old and roll over everything class :silly:
Sometimes I notice a whirling whistleing sound too coming from the case.
Like too much oil being swished around or not enough.
Any scenerio's? Thank You.
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- #8
whyz,
I've received my new clutch, (fibers, metals and springs), but haven't installed yet. I'm cautiously hopeful that this is the problem but have my reservations. When comparing the new plates to the old; I'm kind of wishing I'd just purchased new springs in the interest of not spending a bunch of money when I don't know for sure what's going on. Anyway, I've got the new fibers marinating in type F ATF now and plan on riding night practice Friday night. I'll update after that.
Thanks
I've received my new clutch, (fibers, metals and springs), but haven't installed yet. I'm cautiously hopeful that this is the problem but have my reservations. When comparing the new plates to the old; I'm kind of wishing I'd just purchased new springs in the interest of not spending a bunch of money when I don't know for sure what's going on. Anyway, I've got the new fibers marinating in type F ATF now and plan on riding night practice Friday night. I'll update after that.
Thanks
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- #9
This situation has gone from bad to worse. Let me expound. I installed the new clutch components with hopes that this would resolve the issue. Unfortunately it didn't. So I pulled the motor and sent it back to Wisconsin. Eric disassembled it to find a bad crank seal. Furthermore, the new piston had been destroyed; presumably from burning tranny fluid? Fortunately the cylinder was still OK. So Eric re-rebuilt the motor. New crank bearings, seals, piston, rings, etc.. I now have two rides on the bike with the re-rebuilt motor. Unbelievably, the tranny oil is still fouling out just as before. Quite frankly, I don't know what to do now. This is prime riding season in Texas. I'd like to just keep on riding it but I'm concerned that continued use will ruin this new piston (if it already hasn't) as it did the first one. I've spoken with Eric at length on the issue and we don't know what to do. Quite frankly, I feel bad about calling him back on it because he's been so good about trying to resolve the issue.
Here is what I know: The tranny oil is being contaminated. It becomes a very dark coffee like color very quickly. It's not cloudy and my radiator level is consistent so I think it's fair to say that it's being contaminated by the combustion chamber. I've run ATF type F for years in this bike and it's never fouled like this; until after the rebuild. Something is definitely wrong.
Let's assume that the crank seals are fine. They've been replaced twice now. Getting a bum seal once I can see, but twice in a row; unlikely. So based on this rationale the contaminant is entering the gearbox in some way other than the crank seal. This is where I need help. How else could combustion related product enter the gear box? Could it enter through the powervalve governor somehow? Judging from the color of the contaminated fluid, I think the contaminant has already been burned.
I'd be grateful to hear anyone's feedback.
Here is what I know: The tranny oil is being contaminated. It becomes a very dark coffee like color very quickly. It's not cloudy and my radiator level is consistent so I think it's fair to say that it's being contaminated by the combustion chamber. I've run ATF type F for years in this bike and it's never fouled like this; until after the rebuild. Something is definitely wrong.
Let's assume that the crank seals are fine. They've been replaced twice now. Getting a bum seal once I can see, but twice in a row; unlikely. So based on this rationale the contaminant is entering the gearbox in some way other than the crank seal. This is where I need help. How else could combustion related product enter the gear box? Could it enter through the powervalve governor somehow? Judging from the color of the contaminated fluid, I think the contaminant has already been burned.
I'd be grateful to hear anyone's feedback.
bclapham
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i wonder if soemthing changed with the formulation of the particular oil? maybe now it has a differnt additive that is causing the problem, or maybe the new clutch material has something that reacts with that particular oil? why not try a regular oil just for comparisons sake and then the oil can be ruled out of the equation.
elimination each variable, Mr Watson!
if we are assuming the crank seals are good, then this suggests that the pistons will be OK also. what does the plug look like?
elimination each variable, Mr Watson!
if we are assuming the crank seals are good, then this suggests that the pistons will be OK also. what does the plug look like?
marcusgunby
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I would look at the piston to try to confirm the oil is getting into the combustion chamber, if so then assume the combustion is contaminating the oil.The other area is the seal between the cases-on the KX you use a horrible liquid sealant(that happens to be the same colour as the cases, so its hard to tell if its evenly applied)and its possible it isnt sealing perfectly(maybe one of the cases isnt perfectly flat?) this maybe a really bad idea and i would look to others to tell me if so, how about removing the top end, then blocking the tranny vent, fill the gearbox to the brim and pressurise very slightly (maybe 2 to 4 psi) on the hole where the oil goes in.Then look for any signs of oil entering the crancases with a maglight??maybe this wont work, as the crank seal may seal better this way?ie under positive pressure.
Eric/rich/deanfastaway?? is this barmy???
Eric/rich/deanfastaway?? is this barmy???
darringer
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MXTex, A few years ago I had an 87RM125. Thought it had a leak between the cases. So, (without the top end on), I made sure the filler plug was on snug, and pressurized the cases through the tranny vent. I only needed about 5-7psi. I then waited for the pressure to either hold, or drop, which would indicate a leak. Unfortunately, I had a bad center gasket leaking into the bottom end of the motor. This might work for you. I hope you figure it out. The problem itself is bad enough. But not knowing is even worse.
Good Luck, Darrin
Good Luck, Darrin
You could also have a head gasket leak that is polluting your coolant and destroying your piston also,but you have to have a water pump seal leak for that to get into your tranny.What color is your coolant? I know you said your coolant is consistent,but did you check the color. I am going to have to disagree with the liquid sealant for the cases. I much rather use a good case sealant like 3 bond or yamabond or kawa sealant than a paper gasket like crs and rms.Fuel will break down paper gaskets before chemical resistant sealant that yama and kawa uses.I also doubt it is clutch related, kawa uses steel plates I have gone out for 3 outings before with the oil looking like new.
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jmics19067
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if the oil is turning black rather quickly I would suspect fuel or combustion byproducts. Plus thefact that Eric found a bad seal or atleast symptoms indicating a bad seal.If it is turning dark purple and smelling burnt I would guess that it is the clutch slipping. whether by your fault of hand or within the baskets.
2 quick stupid things I would do right off the bat would be to pull of the powervalve cover and make sure no spooge is running down from a bad powervalve seal. That and with fresh clean fluid take it for a casual ride without using the clutch at all and check the color. If you can switch gears and roll the throttle on smoothly from part throttle to full without using the clutch at all and the color doesn't change the clutch is probably slipping if still changes you can probably eliminate the clutch.
I like the idea of filling up the trans but if it has a double lipped seal you are probably right Marcus it would seal better. How about filling up the trans plugging the vent and pumping up the engine looking for bubbles or fluid trying to escape the filler neck and using a vacuum tool to put a slight vacuum thru the spark plug hole and seeing if the fluid level drops. Isn't that the direction of forces that the seal would usually see anyway?.
if you see something conclusive well now you get to try and figure out whether it is the seal, crankcase halves sealing or poor castings<cracked or porous>.
I had run across a bizarre problem once that I caused myself. having stripped the paint off the engine cases I caused the seals not to set tight enough in their bores and they pop out. After the second set of seals failed I realized what I did and had to paint up the seal area again. And it actually cured my problem on that particular bike.
2 quick stupid things I would do right off the bat would be to pull of the powervalve cover and make sure no spooge is running down from a bad powervalve seal. That and with fresh clean fluid take it for a casual ride without using the clutch at all and check the color. If you can switch gears and roll the throttle on smoothly from part throttle to full without using the clutch at all and the color doesn't change the clutch is probably slipping if still changes you can probably eliminate the clutch.
I like the idea of filling up the trans but if it has a double lipped seal you are probably right Marcus it would seal better. How about filling up the trans plugging the vent and pumping up the engine looking for bubbles or fluid trying to escape the filler neck and using a vacuum tool to put a slight vacuum thru the spark plug hole and seeing if the fluid level drops. Isn't that the direction of forces that the seal would usually see anyway?.
if you see something conclusive well now you get to try and figure out whether it is the seal, crankcase halves sealing or poor castings<cracked or porous>.
I had run across a bizarre problem once that I caused myself. having stripped the paint off the engine cases I caused the seals not to set tight enough in their bores and they pop out. After the second set of seals failed I realized what I did and had to paint up the seal area again. And it actually cured my problem on that particular bike.
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Thanks for all the incredible feedback. The Dirtrider net is such a great resource.
I pulled the top end and thankfully the piston is still OK. In the bottom of the crankcase, was a bit of fluid very similar, if not exactly the same as the fouled fluid coming out of the gearbox. There's just enough in there to make contact with the counterbalancers as they swing low. In the upper part of the crankcase, (just below the cylinder base) was a smattering of bright red fluid that looked just like my my tranny fluid (ATF type F) or my premix (Motul 800). I don't know which it is.
Man I'd love to think this is just a gearbox fluid selection issue, but I've been running this stuff (ATF type F) too long with no issues. I still run it in my son's KX65 with no fouling issues. I'm convinced that somehow my gearbox is being contaminated by the combustion chamber. Is it possible that the new fluid dynamics created by the 2mm over kit are blowing out my crank seals? Many moons ago, when I first got this bike, I had Eric port the cylinder for more better everywhere. I didn't like the loss in bottom end so I sent it back and I believe he shaved the cylinder base and recessed the head accordingly. It's ran great after this with no issues for years. Could this mod coupled with the new 2mm over be creating too much crankcase pressure and thus blowing out my crank seals? I know I'm reaching here but am trying to think out of the box.
Bottom line is I've taken the bottom end to a local shop (JM Racing) for another case splitting and inspection. I'll post the results and some pictures if I can get my hands on a digital. Thanks again for all the help. I'd like to hear any additional feedback or ideas.
I pulled the top end and thankfully the piston is still OK. In the bottom of the crankcase, was a bit of fluid very similar, if not exactly the same as the fouled fluid coming out of the gearbox. There's just enough in there to make contact with the counterbalancers as they swing low. In the upper part of the crankcase, (just below the cylinder base) was a smattering of bright red fluid that looked just like my my tranny fluid (ATF type F) or my premix (Motul 800). I don't know which it is.
Man I'd love to think this is just a gearbox fluid selection issue, but I've been running this stuff (ATF type F) too long with no issues. I still run it in my son's KX65 with no fouling issues. I'm convinced that somehow my gearbox is being contaminated by the combustion chamber. Is it possible that the new fluid dynamics created by the 2mm over kit are blowing out my crank seals? Many moons ago, when I first got this bike, I had Eric port the cylinder for more better everywhere. I didn't like the loss in bottom end so I sent it back and I believe he shaved the cylinder base and recessed the head accordingly. It's ran great after this with no issues for years. Could this mod coupled with the new 2mm over be creating too much crankcase pressure and thus blowing out my crank seals? I know I'm reaching here but am trying to think out of the box.
Bottom line is I've taken the bottom end to a local shop (JM Racing) for another case splitting and inspection. I'll post the results and some pictures if I can get my hands on a digital. Thanks again for all the help. I'd like to hear any additional feedback or ideas.
marcusgunby
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I dont think its the fluid(ATF) and i dont think its the big bore as such, its not really evidant that you have a major problem at all this time around.The oil is changing colour but thats not really that unusual.Having a pool of oil in the crankcases is normal, and the piston this time sounds ok.So is this a real problem? i would still think its a good idea to pressurise the gearbox vent to 4psi and see if more oil comes through.Let us know what you find.
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- #18
I appreciate your comments very much Marcus. You're always very helpful. Man, this situation is killing me. I'm in agreement with you regarding the ATF and big bore not being the source of the problem. But I'm very sure the tranny fluid discolorization is not normal. Prior to the lower end being gone through, the fluid always drained out a nice red; just like it went in. There was maybe a slight smattering of silvery dust mixed in; but that was it. I would normally drain it after 3 or 4 rides and it would always look this way. I've owned the bike since 99 and have always run ATF so am sure of this. Now it turns almost black after 1 ride. As much as I want to think nothing is wrong, I can't. Whatever the source of the contamination, I feel it's probably the same as after the 1st rebuild; which ultimately ruined the 1st piston. So the way I'm looking at it, I have no options other than to find the problem vs continuing to ride and ruin a second piston.
Lesson learned; I'll be hard pressed to ever have a lower end rebuilt again. To do it over again, I'd sell the bike while the lower end was still ok and buy another bike. I love this bike, but I now have way more money wrapped up into it than it's worth. Furthermore, I can't sell it like it is so I have to spend more to have it fixed. Then once I have it fixed I'll feel obligated to keep it in order to justify all the money I've sunk into it. So I'll probably be riding this 98 model bike until 2005 when I could be riding a later model bike for less money.
I've always laughed at my friends that buy a new bike every year and sell their one year old machine. Look who's laughing now. :eek: :laugh:
Lesson learned; I'll be hard pressed to ever have a lower end rebuilt again. To do it over again, I'd sell the bike while the lower end was still ok and buy another bike. I love this bike, but I now have way more money wrapped up into it than it's worth. Furthermore, I can't sell it like it is so I have to spend more to have it fixed. Then once I have it fixed I'll feel obligated to keep it in order to justify all the money I've sunk into it. So I'll probably be riding this 98 model bike until 2005 when I could be riding a later model bike for less money.
I've always laughed at my friends that buy a new bike every year and sell their one year old machine. Look who's laughing now. :eek: :laugh:
marcusgunby
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I hate doing bottom ends and the problems that comes with them:(.I still wonder if its clutch wear on the basket or the extra power causing slight slippage.When i helped out a top rider he could make the fluid go black in 45 minutes.Im interested in how it turns out.
Tex,
I have the same setup as you on an '01 and I also run type F. My fluid changes colors fairly fast and always has. I haven't really paid enough attention to be able to say 1/2 hour or 5 hours of actual ride time though. I usually change it every 2 or 3 rides depending on the length of rides. I just changed it and will pay attention to the time it takes to discolor so I can give you an idea. BTW I'm running the stock fibers, springs and aftermarket steel plates.
SeniorKX has your exact bike and also runs type F, maybe he can also give some feedback.
I see your engine is at the shop so this may be OBE. Two thoughts: check the crank case vent hose to make sure it isn't clogged (you prolly already did) and do as Marcus suggested and have the shop do a pressure check.
I have the same setup as you on an '01 and I also run type F. My fluid changes colors fairly fast and always has. I haven't really paid enough attention to be able to say 1/2 hour or 5 hours of actual ride time though. I usually change it every 2 or 3 rides depending on the length of rides. I just changed it and will pay attention to the time it takes to discolor so I can give you an idea. BTW I'm running the stock fibers, springs and aftermarket steel plates.
SeniorKX has your exact bike and also runs type F, maybe he can also give some feedback.
I see your engine is at the shop so this may be OBE. Two thoughts: check the crank case vent hose to make sure it isn't clogged (you prolly already did) and do as Marcus suggested and have the shop do a pressure check.
I'm still changing oil after every ride.
Noticed this a couple of weeks ago about the containers.
The front top said Federated,and underneath it had the name Auto Parts in a square background that was orange.
And below that it has Type F,,then below that,
Automatic Transmission Fluid. Oil was Red.
The other container read the same thing but the background was a slight brown color and so was the oil,,it wasn't red.
Now I'm confused :think:
Noticed this a couple of weeks ago about the containers.
The front top said Federated,and underneath it had the name Auto Parts in a square background that was orange.
And below that it has Type F,,then below that,
Automatic Transmission Fluid. Oil was Red.
The other container read the same thing but the background was a slight brown color and so was the oil,,it wasn't red.
Now I'm confused :think:
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- #22
OK guys; light bulb just may have gone off here. Please give me your thoughts on this. When I pulled the motor this last time, just for grins, I removed the tranny filler cap, sealed my lips around the hole and blew into it. I was not able to blow through the gearbox. It exhibited being sealed. I really didn't think much of this until I read bscottr's response regarding the vent hose. I should have been able to blow through the vent tube. I did this with the hose off so presumably the vent is clogged from within. I could rationale that this would created pressure in the gearbox and force fluid by the crank seal. What do you guys think? Am I onto something here?
MXTex,
I think so... HOPE so! :thumb:
Save some $$$ if so.
Heat expansion of the fluid and the action of the clutch/gears would pressurize the case I’d think. Also without a vent to the case I believe condensation buildup may also contribute to the discoloration.
Go check that hose man! :)
jmics19067
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if the vent was plugged whatever pressure that is created by heat is going to have to find some way out. I think you have a good chance this is your problem.
Having watched this thread, I have my fingers crossed for ya, Tex!
