Milky engine oil, couple questions

[whizzit]

Went to let some oil out yesterday, showed a little high on the dip stick. Then my heart sank, all that was coming out was chocolate milk. Blew a seal somewhere I guess, from reading it looks like it might be the water pump.

My question is, if the milky oil has been in there for, say 2 weeks, would that do any damage to bearings or anything else?

Also from reading a lot of other posts on milky oil I've heard: engine oil, tranny oil, clutch oil. I know clutch oil and engine oil, but what is tranny oil? Is it clutch oil or engine oil? I would guess engine, just a little confusion on that one.

Also, this milky oil wouldn't make bike hard to start, impossible to start would it? I'm thinking the spark plug went coincidentaly the same time I blew a seal. I have a 2007 crf250r, not a ever fouling 2 stroke.

On a side not, just shimmed the valves.... surprisingly easy.

 

[whizzit]

Never mind about the engine, tranny, clutch question. Tranny/clutch same thing.

 

[BSWIFT]

Shouldn't be a big concern. Put some fresh oil in and change soon after you have replaced the bad gasket.

 

[julien_d]

I second BSWIFT. It's a pretty common problem with a relatively cheap and really easy fix. Changing the oil again soon after stitching it back up is a good idea as well. Most likely some residual h2o will be hanging out in there.

 

[whenfoxforks-ruled]

How the heck does chocolate milk colored oil relate to a coolant leak? I would be under the impression its clutch material, and you went too long on changing it/ very abusive to the clutch. Coolant in the tranny appears to look like milk, not chocolate, or strawberry either! Take a sample in a clear small container, and let it sit over night, if there is coolant in there it will separate. Memory refresher, the water pump is in the tranny oil, or engine oil?

 

[julien_d]

Nasty old black crankcase oil + coolant = chocolate milk. My vote still goes for leaky water pump seal, especially given the mention of higher than expected fluid levels in the crankcase. I don't care how much wear the clutch plates take, it's not going to cause a noticeable rise in fluid levels.

I could be wrong, and if so, feel free to say "i told you so". I'd bet a dollar on it though.

 

[rmc_olderthandirt]

I agree with the water in oil diagnosis. Well churned four stroke oil and water looks a lot like Nestle's Quick.

As for suddenly getting hard to start: you might have blown a head gasket. Did the bike stop running when all this happened, or did you notice the milky oil and then start having difficulty getting it to start? Do you get it started? How does it run?

It is common for a head gasket to fail in a "blow out" fashion that can open up chambers that are supposed to be separate. On a Two Stroke this is limited to the outside, cooling and cylinder. On a four stroke there are also oil passages, timing chain, etc. so a blown out head gasket can open a path between the cooling system and the oil space.

I recommend a compression test before you start tearing into the water pump.

Rod

 

[robsterzallan]

My water pump went out and my oil was white. all i did was replaced the water pump propeller shaft, and the seal for it and everything was fine after that.

 

[whenfoxforks-ruled]

Put it in a clear jar, oil will separate from water.....

 

[whizzit]

I was just in the big city and picked up some new spark plugs. I'll try a compression test before I change the spark plug, since I'll have the gas tank off. And I'll probably disassemble the water pump and hopefully find the fault. I'll post something when I find out.

As for the what kind of "milk" the oil is. This will have to wait till I get to the grocery store to do some comparative sample analysis...

 

[whenfoxforks-ruled]

I for one am more interested at the results of the what the original suspect oil has done, as far as separation? Different opinions of what milk color actually is, well yes, from what I can tell, seemingly, we are a bunch of guys arguing over what "milk" color is, its not a color, its food!

 

[julien_d]

I for one am more interested at the results of the what the original suspect oil has done, as far as separation? Different opinions of what milk color actually is, well yes, from what I can tell, seemingly, we are a bunch of guys arguing over what "milk" color is, its not a color, its food!

LOL!

 

[whizzit]

Well so far I've checked for spark, I have spark. I replaced the spark plug with a new one anyways. Got the bike running by push starting it and cracking the throttle a little. This was tried after many many attempts at kick starting it. We knew about the oil, we just wanted to deal with the bike not starting first.

Couldn't check for compression, I don't have the proper size adapter for the smaller 4-stroke spark plug hole. Apparently they are smaller than 2-strokes and other engines. Its hard to tell from kicking it, if it has lower compression or not. I'll get a fitting from work tomorrow to check.

I changed the oil after running it a little... pure milk. Before was parts of milk and oil(separately), now just pure milky oil. I didn't get to taking a sample of it to let it separate unfortunately, just drained it in the oil pan with all the other oil changes.

Next move from what we can guess is:
a) cylinder gasket or head gasket (cylinder head gasket) is passing. Maybe reason it is hard to start as well.
b) water pump seals are passing.

I'm ordering all of these, plus some other parts, to fix for upcoming race this weekend.

We are leaning towards cylinder gaskets. Giving me a good time to replace piston/rings/pin as those are due. There is no oil/water leaking down from the water pump check hole, although that could be plugged.

Would the compression test ultimately tell me if the coolant/oil problem is either the cylinder gaskets or the water pump? No parts available in town, so I am thinking of ordering all possible parts just in case. Race this weekend so a little bit of a deadline.

 

[whenfoxforks-ruled]

Do you have access to have the valves replaced and seats recut? Top end, inspect the cam, check the thrust washers on the crank? The clutch will need a thorough checking? Without actually knowing where the coolant is coming in? An after market impeller, bearing and seal? Compression checking is good if you do it fresh, and keep checking it. What could really be useful in your situation is a leak down test, by someone who has experience reading the values, it could nail the problem area.

 

[_JOE_]

You can't compression test an auto decompressing engine.

Sounds like you need to take another look at the valve clearances and cam timing.

 

[whizzit]

I finally got around to getting the cylinder/head all off. Hard to say if I found where the cylinder gasket blew. I found one spot right where the coolant leaves the pump and goes into the water jacket. Part of the gasket material was left behind on the crank case (thing metallic film). Sorry no pics, fiancée took the camera out of town. This is the only place that left behind part of the gasket. Anyone have any or know where I can see some pictures of a blown cylinder gasket?

Whether it is or not I suppose I'm just going to put it back together today anyway with new gaskets, plus new piston/rings/pin. I never got all the gasket to change out the water pump seals.

Too late to do a leak down test I guess. I would really like to get one of those tools. A coolant pressure test kit or whatever its called. Or maybe make one if I knew how.

 

[_JOE_]

A pressure tester is just a pump used to pressurize the cooling system to allow you to look for a coolant leak under pressure.

A leak down test uses an adapter you thread into the spark plug hole and then hook to pressurized air. This will tell you if you have any combustion chamber leaks in a 4 stroke or leaking crank seals in a two stroke. This would help diagnose poor valve seal in a 4 stroke.

 

[whizzit]

Anyways, I'm good with the valve clearances. Valves are not the issue here. Bad gasket is, which ever one it is. If it works when I'm done putting the engine back together then it must have been the cylinder gasket.

 

[_JOE_]

That's right.....

 

[whenfoxforks-ruled]

Was the gasket tore when you took it apart? Like, some bozo did not use a new gasket?

 

[2strokerfun]

Was the gasket tore when you took it apart? Like, some bozo did not use a new gasket?

I am offended! I have proven many times that I am perfectly capable of tearing a brand new gasket!! I don't need no schtinkin' used gasket. (And they say I'm "unskilled".....)

 

[whenfoxforks-ruled]

Oh I have gotten away with out new gaskets, once or twice. But, a torn gasket, part still stuck on the cases, and thinking it will seal, is not going to happen. Not even miracle sealer 1000000 will help!