milky oil

[fargofour]

Hi,

I can't remember if I posted on here or not about this so I'll go again. It's kind of long so...

I got my 99 SE in 2015. Had lots of work to do since the PO hit a moose. Had it running for about two years with no problems, ran great. Put the bike away in fall of 2017 for the winter. Took it out in the spring. Changed out the winter oil and noticed milky substance in the oil. Changed the oil and ran the bike about 15 minutes, same thing.

Over the course of 2018 I replaced the head gaskets, replaced the water pump, even replaced the radiator cap. Still milky oil. Did a cooling system pressure test and it passed. Finally gave up and put in storage at the end of 2018. 2019 I spent tearing down the old garage and built a new one.

Spring 2020 comes and I'm back at the same place, milky oil after about 10 minutes running with fresh oil. I cannot for the life of me figure this out. Due to a screw up on my part I had to remove the engine (what a trip) and replace some starting system parts in 2018.

I now have the carbs back out to look at all the hoses on the top of the motor. I'm thinking of pulling the manifolds just to get a better look at the hoses.

So if you finished this, any other ideas?

thanks,

Bud.

[fargofour]

A couple other things.

Compression was four cylinders at 180 or 185, one at 170 and one at 190.

No white smoke coming from the exhaust. No condensation dripping from the exhaust.

Thanks again,

Bud.

[Viking]

What brand and quality of oil are you using? Poor quality oil will show contamination from moisture just from running the engine as a byproduct of fuel consumption is heat and moisture. Better quality oils will accept a certain amount of moisture into their substance, and then evaporate it off through the PCV system. You also might check to ensure that system is clear.

[fargofour]

Lucas motorcycle oil.

What brand and quality of oil are you using? Poor quality oil will show contamination from moisture just from running the engine as a byproduct of fuel consumption is heat and moisture. Better quality oils will accept a certain amount of moisture into their substance, and then evaporate it off through the PCV system. You also might check to ensure that system is clear.

[fargofour]

This is after running about 10 minutes on brand new oil.

[Viking]

Well, that don't look good do it. That looks like more than just some stray condensation. Do you have oil showing up in your coolant as well?

[fargofour]

Nope.

Well, that don't look good do it. That looks like more than just some stray condensation. Do you have oil showing up in your coolant as well?

[Viking]

I just wonder if there had been enough sludge inside the engine that is washing off into the oil to make it look like it does. I am not familiar with the properties of Lucas Motorcycle Oil, but it should be fairly high detergent, so this is possible. With no leaks coming into the engine from anywhere, this is the only thing I have left. If you had a blown head gasket, you would expect oil in coolant when the running oil pressure got higher than the coolant pressure, as well as the milky indicators of water in the oil from when the coolant pressure is higher than the oil pressure when the bike is not running, after just shutting it off. The PCV system is working and there should not be enough moisture from ten minutes of running to slime up the oil. I would run it for a bit with that same oil back in it, or if you have already changed it out, then run that oil for a while, like a couple hundred miles, to see if you can finish washing out the sludge (if that is the problem) I am not advising you to do this - It is just what I would do. When you change the oil again, try a different product. Keep your ears open to any differences in the way the engine sounds. And now - that's all I got. Good luck and I hope this works itself out.

[fargofour]

With all the work I've done on it I would guess I've put about 8 - 10 gallons of oil thru the motor. I appreciate your advise but as I have the carbs off I'm going to take the manifolds off and look at all the plumbing in there to see if I have anything crossed/open/or whatever. If all looks OK then I may have to pull the heads, yay.

I'll let you know what I find along the way.

Bud.

I just wonder if there had been enough sludge inside the engine that is washing off into the oil to make it look like it does. I am not familiar with the properties of Lucas Motorcycle Oil, but it should be fairly high detergent, so this is possible. With no leaks coming into the engine from anywhere, this is the only thing I have left. If you had a blown head gasket, you would expect oil in coolant when the running oil pressure got higher than the coolant pressure, as well as the milky indicators of water in the oil from when the coolant pressure is higher than the oil pressure when the bike is not running, after just shutting it off. The PCV system is working and there should not be enough moisture from ten minutes of running to slime up the oil. I would run it for a bit with that same oil back in it, or if you have already changed it out, then run that oil for a while, like a couple hundred miles, to see if you can finish washing out the sludge (if that is the problem) I am not advising you to do this - It is just what I would do. When you change the oil again, try a different product. Keep your ears open to any differences in the way the engine sounds. And now - that's all I got. Good luck and I hope this works itself out.

[MikeB]

Over the course of 2018 I replaced the head gaskets, replaced the water pump, even replaced the radiator cap. Still milky oil. Did a cooling system pressure test and it passed.

I'm just brain storming here because I am not a mechanic, just a guy that likes working on things.

If there is a problem with the head gasket installation or, God forbid, a crack in the block at one of the water jackets, coolant can get into the oil. Usually the coolant system is under pressure and will leak into the crankcase well before oil gets into the coolant system. There is no real oil pressure in the sump, only the oil journals have pressure which I do not believe come anywhere close to the coolant.

Inspect the water pump installation closely. One of the "O"-Rings could be damaged. That is one point I know for sure that coolant and oil can be combined.

What kind of cooling system pressure test did you do and what was the duration of the test? I see in the Honda Service Manual that it calls for it holding pressure of no more than 15 psi for six seconds. Seems like a very short interval. Did you try a longer duration test?

This is just a shot in the dark but I wonder what the outcome would be if the pressure test was done and the engine started? The coolant system should still hold pressure with the engine running since it is a sealed system.

[fargofour]

Pressure test - 15 psi for 20 seconds. I thought 6 seconds was too short also.

Bud.

Over the course of 2018 I replaced the head gaskets, replaced the water pump, even replaced the radiator cap. Still milky oil. Did a cooling system pressure test and it passed.

I'm just brain storming here because I am not a mechanic, just a guy that likes working on things.

If there is a problem with the head gasket installation or, God forbid, a crack in the block at one of the water jackets, coolant can get into the oil. Usually the coolant system is under pressure and will leak into the crankcase well before oil gets into the coolant system. There is no real oil pressure in the sump, only the oil journals have pressure which I do not believe come anywhere close to the coolant.

Inspect the water pump installation closely. One of the "O"-Rings could be damaged. That is one point I know for sure that coolant and oil can be combined.

What kind of cooling system pressure test did you do and what was the duration of the test? I see in the Honda Service Manual that it calls for it holding pressure of no more than 15 psi for six seconds. Seems like a very short interval. Did you try a longer duration test?

This is just a shot in the dark but I wonder what the outcome would be if the pressure test was done and the engine started? The coolant system should still hold pressure with the engine running since it is a sealed system.

[ct1500]

Pressure test - 15 psi for 20 seconds. I thought 6 seconds was too short also.

20 Seconds The cooling system with engine running stays pressurized for hours on end. Pump it up and watch gauge for at least five minutes. Are you losing any coolant? That means checking level in radiator under cap and at reserve tank. If no pressure loss with engine cold you can also check when hot, with some pre-planning.

[fargofour]

I want to thank everybody for the advice. I have come up with a partial plan.

The coolant and oil has been drained. I removed the water pump. It has about 10 hours on it, if that. It seems OK, the shaft is tight in the oil seal. One thing I did notice is milky sludge in the bottom of the front cover.

So I'm removing the from cover and then get a gallon or so of desiel (?) and see if I can flush it out. I'll then go from there.

Bud.

[fargofour]

Here's what was still in the bottom of the engine.

I think an engine flush of some sort is in order.