cr 250 help again !

triple buzz · Apr 6, 2005

hey all, I have a 92 cr 250 with water or coolant in the cases.Some members said I should change the waterpump gaskets which made sense so I did. Still have milky oil . I not sure but if the base gasket was leaking would I not get white coolant smoke ? Could it be leaking at the cases ? please help. :bang:

uts · Apr 8, 2005

When you say coolant in the cases do you mean transmission. If so check for holes in the water pump case itself ( part of rh crank case cover.) They may only be pin size. This is a common problem and allows coolant into transmission. Also the waterpump gaskets only stop water from leaking out of the water pump. You need to check the seals. There is a water seal (water pump side) and an oil seal (transmission side)
If it is the transmission oil you are talking about that is milky (which I think it is) a base gasket leak will no be the culprit.

UTS

Gazza2005au · Apr 8, 2005

the water pump has two gaskets #1 seals the coolant from leaking out of the bike #2 is a small rubber seal that goes behind the water pump (sits in the case and is a snug fit over the shaft) this will be your problem the seal is old and is causing the coolant to leak into the gear box oil making it go grey

joh9356 · Apr 8, 2005

Gazza's right. It's probably the seal behind the pump. Yes, it'a stinkin' pain to replace, but if you have to, you have to.

It is also possible for the case to be leaking, but would be hard to tell without breaking them open.

uts · Apr 9, 2005

For the coolant to get to transmission past the seals, it has to pass the water seal and the oil seal. I have never seen this happen. A hole in the water pump case is more likeley the culprit. The water pump is housed in the right hand crank case cover NOT the crank case itself. So you can search for holes by removing the cover.
Of course both seals may be cactus, I coud be wrong, I am no Jedi.

triple buzz · Apr 10, 2005

thanks to all that replied,I should have put the word seals and not gaskets, I changed the SEALS ! The outside and inside. Had the case off, where should I be looking for holes ? in the channels for the water to the water pump shaft ? thanks again
:nod:

Gazza2005au · Apr 10, 2005

i doubt it would be holes i have a link for u with a picture that will show u the exact seal u need to replace but i cant post links here if u PM me i will give it to you

joh9356 · Apr 11, 2005

Triple Buzz,

OK, I have a 90 model same bike, my pump system is very different from yours. Mine has the water inlet and outlet on pump itself, yours doesn't. If my right case cover gasket fails, I will not have a water leak. If your does in the right place, it will.

You should have one coolant hose going to your pump on the right crankcase cover. This should draw coolant from the radiator, sending it through a port in your crankcase. You said you replaced the seals now, and not the right crankcase cover gasket, right? It is possible for the crankcase cover gasket surrounding the coolant port to the right crankcase could have eroded away. That is more than likely your cause. I am not getting why there are so many thoughts to a hole being anywhere, that is unlikely unless there has been some major catastrophic damage to your system, which is also unlikely being that it would manifest itself with more problems that just a leaky pump system.

However, if your water pump also has two seals, which I believe it does, one to seal in the coolant the other to seal in the tranny fluid, both seals should face each other, with the leak port in the center. This port is just like any other coolant failure port on any vehicle, when the coolant seal fails, the port starts leaking coolant, unless the port is clogged, which is very possible if you do a lot of motocross with your bike. To clean it out, just push a jewelers screwdriver up in the hole(at the bottom of the pump) and twist it gently. Don't worry about the seal, you shouldn't hit it, but be careful you don't gouge the aluminum body too far in the hole.

Now, if you actually did replace both seals the pump rides on, then you would have had to remove the right crankcase cover assmbly to replace the inner seal, in fact replacing the gasket anyway. So if you replaced the gasket and both seals, there should be no mixing of the two, and I guess there is a possiblity of a thermal crack or hole or something instead.

This is my diagnosis:

1) If the outer pump seal is bad, and the coolant pump failure hole is clogged, and the inner seal is good, there should be no sign of a problem.

2) If the above scenario also happens and the inner seal is also bad, what you are now experiencing is possible.

3) If the coolant drain hole is not clogged and the outer pump seal fails, you would definitely see coolant draining from this hole.

4) If the gasket between the pump passage and the tranny area is eroded, you would get exactly what is happening to you now.

5) If you have replaced the gasket and two seals, something is definitely wrong somewhere, and you or a tech will have to find it.

Hope this helps,

Jim

triple buzz · Apr 11, 2005

joh9356 said:
Triple Buzz,

OK, I have a 90 model same bike, my pump system is very different from yours. Mine has the water inlet and outlet on pump itself, yours doesn't. If my right case cover gasket fails, I will not have a water leak. If your does in the right place, it will.

You should have one coolant hose going to your pump on the right crankcase cover. This should draw coolant from the radiator, sending it through a port in your crankcase. You said you replaced the seals now, and not the right crankcase cover gasket, right? It is possible for the crankcase cover gasket surrounding the coolant port to the right crankcase could have eroded away. That is more than likely your cause. I am not getting why there are so many thoughts to a hole being anywhere, that is unlikely unless there has been some major catastrophic damage to your system, which is also unlikely being that it would manifest itself with more problems that just a leaky pump system.

However, if your water pump also has two seals, which I believe it does, one to seal in the coolant the other to seal in the tranny fluid, both seals should face each other, with the leak port in the center. This port is just like any other coolant failure port on any vehicle, when the coolant seal fails, the port starts leaking coolant, unless the port is clogged, which is very possible if you do a lot of motocross with your bike. To clean it out, just push a jewelers screwdriver up in the hole(at the bottom of the pump) and twist it gently. Don't worry about the seal, you shouldn't hit it, but be careful you don't gouge the aluminum body too far in the hole.

Now, if you actually did replace both seals the pump rides on, then you would have had to remove the right crankcase cover assmbly to replace the inner seal, in fact replacing the gasket anyway. So if you replaced the gasket and both seals, there should be no mixing of the two, and I guess there is a possiblity of a thermal crack or hole or something instead.

This is my diagnosis:

1) If the outer pump seal is bad, and the coolant pump failure hole is clogged, and the inner seal is good, there should be no sign of a problem.

2) If the above scenario also happens and the inner seal is also bad, what you are now experiencing is possible.

3) If the coolant drain hole is not clogged and the outer pump seal fails, you would definitely see coolant draining from this hole.

4) If the gasket between the pump passage and the tranny area is eroded, you would get exactly what is happening to you now.

5) If you have replaced the gasket and two seals, something is definitely wrong somewhere, and you or a tech will have to find it.

Hope this helps,

Jim

thanks for the info . both seals changed, and gasket , $16.00 bucks from sevice honda !Looks like I am going to pull the case off again.

triple buzz · Apr 11, 2005

Gazza2005au said:
i doubt it would be holes i have a link for u with a picture that will show u the exact seal u need to replace but i cant post links here if u PM me i will give it to you

the site won't let me pm, says I dont have privliges thanks :)

Gazza2005au · Apr 11, 2005

give me your email i will email to you

cr 250 help again !

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