Why Is There Water In My Oil?

Why is there water in my oil?

I have a 2003 YZ450/487F with significant motor mods:

custom head work with multi angle valve job

WebCams kit - do not know the measurements

Wiseco 99mm piston kit

Carillo rod

Appropriately Bored Cylinder

Balanced Crankshaft

Wiseco Billet Clutch Basket

PWR Double Thick Radiators

Akrapovic Full-Ti System

I got it in a trade. I knew about the mods when I got it

(Oct 2007).

If I hadn't known the engine builder personally,

(Brian Livengood - Loganville, GA) I would have never taken

the trade. I new there was a water leak, somewhere, but I

figured a new water pump would fix the issue and I would have

a monster motocrosser that would make a do-able supermoto.

Well, I put in my third water pump six weeks ago. Put fresh

water in the radiator, fresh air filter, oil filter, and oil.

Buttoned her up and was ready to ride.

Due to my wife's pregnancy, I was not able to ride until this

past Saturday. That's when I noticed the small puddle of liquid

beneath the bike. Put my finger in it - water with oil.

I cranked her up and put-putted up the street and back.

I rode her for literally less than two minutes and put her

back on the stand. Came back out ten minutes later - had to

call my buddies to tell them I would not be riding, yet again-

only to find the small puddle had returned with white liquid

in its place.

So, I pulled her down.I noticed that when I pulled off the radiators,

they were dry. When I drained the oil, nothing but WHITE thick

fluid from the crankcase. When I pulled the valve cover, the

cams and head were covered in the white fluid. When I pulled

off the cams, there was no scarring of any kind. When I pulled

the head, there was some carbon build-up, but no cracks, and

the head gasket was perfect!

I pulled the cylinder (jug) off the case and piston and it

was perfect! The cross hatchings were so perfect, the cylinder

looked like it had never been cranked!

I pulled the aluminum tubes out of the hoses and motor and checked

for any issues, there. They looked perfect! I went over the

service manual many times, and all the oil dowels for the head

and cylinder are in place. The base gasket looked perfect, too!

I have called every other resource I know, and they keep saying

it must the water pump, again! Please, oh great and wonderful

ThumperTalkers, tell me what I am doing wrong!

PS: I will be calling the engine builder, today to see what he

thinks can be done. I will keep this forum updated as to my

progress of this issue.

Thank you in advance,

Frank

Under any normal circumstance, the water pump cannot leak into the engine oil. The shaft has two seals, one for coolant, (lip faces out toward the pump) and one for oil (lip faces in toward the oil). These are separated by a small air gap leading to an escape port, specifically so that either fluid leaking cannot contaminate the other.

Water can enter the oil at the following points:

> The water passage between the right engine cover and the crankcase.

> The water passage between the crankcase and cylinder.

> The head gasket (most likely, unless you messed up on the crankcase cover when you did the water pump)

> A crack in either the cylinder or head.

> A leaking coolant jacket plug (center of the head in the cam box)

Hey GrayRacer,

Thank you for keeping me sane on that one. I spoke with the engine builder

Monday morning after reading your post. Brian said the same thing.

I ordered the new gasket kit from Cometic, and the O-rings for the water passages you mentioned (from the cylinder to the crankcase and from the water pump into the case) as well as new water pipes, just to be safe.

All those parts will be in, next week and will let you know how it all comes

together.

I learned something new in this process. Wiseco doesn't offer the 99mm

piston kit in their catalog. The guy I talked to transferred me to their

"special parts" division. The gentleman I spoke with there, told me this was

a "prototype" piston developed specifically for supermoto and dirt track racing.

I guess that would explain the 61 hp Brian said it turned on his dyno. :banghead:

BTW: Yes, the bike is a handful on smaller tracks, and I would not even consider trying to manage this beast on a trail!

Thanks again, Grayracer!

Frank

Next time you put it together, use a cooling system pressure tester to check for leaks before firing it up. That will be nicer for the engine parts that prefer to run in pure oil. :banghead: The pressure testers are available almost anywhere, even Sears. You can pump it up first with air only and see if it holds pressure. If it leaks you can keep pumping air in and start listening for the leak.

Hey Sir Thumpalot,

Thank you for your advice! I had not considered that, before. Actually,

I did not know there was such a thing! I will stop by Sears and pick up that

"coolant system pressure tester".

Again, kudos to the great and wise ThumperTalkers!

Frank

Hello again great and wise TT-ers!

The saga of this poor yamaha continues. You can read the above about this bike, and here is the new problem.

I got all the new gaskets in. I installed all of them, new head and base gaskets, as well as the new rubber seals for the water pipes. (the one coming from the wanter pump into the engine case - and the one coming

from the engine case up into the cylinder) I put it all back together, made

sure the timing was perfect, and she fired up on the 21st kick!

The next day, I took her out to the local track (Three Palms - conroe, tx).

I did a few moto's, got tired, brought her home. No issues. I was rather happy.

Went home, changed the oil and filter. There was no water in the oil - and my happiness continued. Two days later I went back out to the track to start getting ready for the local race series. Rode one easy three lap moto

to warm up. After 15 minutes, I went out for a second moto. The bike started easily. I put her in gear, and as I pulled out onto the track, the

bike starte sputtering and back firing badly. I pulled over and checked the petcock, fuel was on and still had a full tank. The motor idled nicely, but whenever I tried to ride it, the backfiring and sputtering was so bad that

the bike was unrideable.

I eased her back into my pit, and changed spark plugs. She fired back up, easily, but ran just as badly as before. I did not know what else to do, so I packed her up and brought her home.

I pulled off the carb, cleaned the pilot jet (K42) which was clogged, checked the main (K180) which was clean, and cleaned the air jet which was partially clogged. Put it all back together, and tried it again. Now the bike would not start at all! (35 or 40 kicks)

I pulled off the carb, and drained the oil. There was now water in the oil again - AAARRRRGGGGHHH!!!!

What do I do now?

BTW: I tried the plug, it was fouled. Put a new one in (NGK CR10 EK). I checked for spark (by shocking my self on the new plug) and checked the carb again (squirts fuel perfectly and the jets are all clean.) What now?

> A crack in either the cylinder or head.

A crack in the cylinder can get the the opposite; Oil in your Water.

Perhaps the head is warped, since the gasket cured it for awhile???

A crack in the cylinder can get the the opposite; Oil in your Water.
If a crack exists between the cam box area, which is not under any particular pressure, and the water jacket, which is capped at 16 pounds in a stock system, which way do you think the fluids will flow?
If a crack exists between the cam box area, which is not under any particular pressure, and the water jacket, which is capped at 16 pounds in a stock system, which way do you think the fluids will flow?

Your right, if it is in that area. :smirk: I don't think that is his problem though, since it stopped for a short time.

I don't either. and in as muchj as it is a big bore, the head gasket is the most likely cause.

The list I posted includes cracked heads, which frankly are a very rare occurrence in a YZF, because it was intended to be all-inclusive.

I am sorry this has stumped someone as experienced as you gray racer. I will go through the process, again. I will disassemble the top end, go through the rubber gaskets, then reassemble.

I will keep you posted on the results. Thank you for your time.

Frank

I don't feel stumped by it at all. I just don't have anything else to offer you without being able to inspect the parts in person. :smirk:

I did just say that your head gasket seems the most likely suspect, so perhaps you should consider having the head and cylinder checked for flatness. If you suspect cracks, an auto machine shop capable of pressure testing aluminum heads should be sought. However, as we also said earlier, cracks don't seem likely based on history or your symptoms.

In any case, I can only tell you what I know about it. You will have to read the parts, make the diagnosis, and effect the repairs from there. Your vantage point is far better than mine.

I did just say that your head gasket seems the most likely suspect, so perhaps you should consider having the head and cylinder checked for flatness. If you suspect cracks, an auto machine shop capable of pressure testing aluminum heads should be sought. However, as we also said earlier, cracks don't seem likely based on history or your symptoms.

.

i agree on having it checked for any warping in the head.

Will do, then. I will have it checked for warpage, leakage, then go from there.

Thank you, again, all!

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