Water in the oil?

4 replies to this topic
  • Tom_N

Posted January 19, 2001 - 09:25 AM


I just got my bike back from the shop who replaced a bent valve. The bike had just gotten out about 2 weeks before that after just having the Crank, rod, piston and cam chain replaced.. So I ran it for about 20 min last night and runs great but when I was done I checked the oil and it came out VERY thin and dripy (technical term there) and was somewhat discolored. It was more clear than amber and actually kind of light grey.. Its got fresh 20-40 in it but the oil just did not look right. Could coolant be getting into the oil some how? If so HOW? and what would be a way to test for this??

Is it just the yamalube breaking down?

  • Hick

Posted January 19, 2001 - 10:21 PM


Don’t forget the obvious. Check your coolant level, if it disappearing then you know the answer.

It may be leaking at the base gasket o-ring or the right cover o-ring. It could be the water pump seal as well, but only if the weep hole is plugged or something, when water gets by the first seal on the impeller shaft there is a passage in the case that allows it to vent before it gets by the second seal into the cases. The weep hole exits the cases just above the water pump guard and will spit water all over your toe.

But it does sound like you ended up with some water in your oil. Time for a new mechanic.

Hey, didn’t you ask them to check the impeller shaft and seal when they were replacing the valve? Maybe they didn’t grease the seal or, God forbid, the gomers put it in backwards (okay, okay, I did that once too). Find the weep hole and make sure it isn’t clogged, spraying some WD-40 up it won’t hurt, then warm up the bike and see if water is coming out here.

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  • Guest_Guest_*

Posted January 19, 2001 - 11:13 AM


TOM N, how did you know that you had a bent valve did the bike run differnt. Right now I'm in the middle of trying to troble shoot a problem with my bike. It had a sudden lack of power specially in the lower rpm range.

When ever I had water or colant mix with oil it would turn a whitish color.

  • Tom_N

Posted January 19, 2001 - 11:27 AM


Well, I just got back from the shop and had them look at the oil and it did not look bad. They said there was not any water in it just starting to turn dirty.. I may have over reacted because of all the problems I have been having with the bike and the Mech.

I don't see any coolant level changes and the weep hole is working. I did have them check the shaft, said nothing was wrong with it.. who knows if they did it or not..

When my valve bent the motor died and would not gain compression. I would kick it and could feel compression on the piston but nothing came out the exhaust pipe but it blew air back through the carb with each kick. They pulled it appart and found the bent valve. What suck is that I orig. took it in with a noisy engine and asked them to check the valves because they were what seemed to be knocking.. They said the valves were spec-ed but I needed a piston, connecting rod & bearing and rebuild on the crank... $1200 later I got it back not really any quieter than it was when it whent in. I put about 5 hour max on it when I had changed the oil, cleaned the plug, service the air filter and flushed the radiator.. I then went for a ride and 20 min into it the valve stuck open. They blamed the whole thing on me saying I must have over reved it, mike bike did not have a rev limiter (bull !@#$) etc etc... I complained and all they would do is split the labor.. So it cost me another $200 and guess what the motor is nice and quiet (as much as a 4stroke can be). I think the valve had problems all along and was probably all that needed service! Oh well I guess the gutts of the motor are atleast in fresh shape.. Still sucks.. Now I just have learn how to tune the darn thing as the carb is not performing well at all... I think it needs some service and tunning.. I will have to learn to do that my self rather than take it to the shop again..

Wow that was long but I am feeling much better now :)

I think if you had a bent valve it would not run at all, mine did not... maybe a valve spring or something is causing the valve not to seat properly but I would think it would be something simpler first.. Or hope it is.

Thanks guys!!! I will keep reading and still planning that colorado trip!! Lets GO!

Tom N.

  • holeshot

Posted January 19, 2001 - 11:36 AM


Tom N.

I would have taken them to small claims court for the full 1400.00. It's ugly, but sometimes that's what it takes.

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