Veloce oil/water emulsion

[backfat1187]

Hi all
So during servicing the Corsaro, I've discovered the dreaded oil/water creamy emulsion. It appears to be more oil in water than water in oil although that is by no means a scientific assessment.
Causes I can think of are; a head gasket or the water pump shaft seal. Can anyone suggest any other possibilities?
I can't tell just by looking at the shaft seal. I'm going to do a compression test tomorrow.
Can I do this by manually turning the motor over or do I need to refill with oil and do it on the starter?
What sort of values should I be looking for? Although I am assuming that if a gasket has gone, the cylinders will read differently.
I'll be a bit peeved if it's a head gasket as they were new last spring and I followed the manual to the letter using the revised tightening pattern with a good quality torque wrench.
I also renewed the shaft seal and was extremely careful when refitting the timing cover.
Grumble grumble.

[eddydog]

Hi, you need to check shaft place where contact with seal, may be wearing and need or repair or changing shaft with bearing.
had the same sign. antifreeze in oil. ended with the replacement of the water pump shaft.

[backfat1187]

Thanks eddydog
I'll get the timing cover off today and have a look.

[backfat1187]

Timing cover off today. The pump shaft looks in reasonable shape to me. You can see the difference in colour where the seal sits on the shaft and can feel the very slightest bit of wear. It's like there's a tiny change in surface texture. Detectable by finger tip, but feels perfectly smooth if you run the end of your fingernail along it. No visible wear as such. Nothing like eddydogs.
Compression test was inconclusive due to the de-compressors. I did get around 60 psi consistently from both pots though, which is mildy encouraging.
I popped in to see the good gentleman at NLM today. Chris was inclined to think that it was unlikely to be a head gasket. Also mildly encouraging. He also advised doing a leakdown test. I'll do that next.
It's impossible to determine the state of the shaft seal really. I'll just replace it. This time though I'll make a seal bullet out of brass to make absolutely sure there's no damage to the seal on installation.
And here's me thinking I might actually make it to the April Corsaro section meet! Maybe May...

[Tonibe63]

Yes a 'leakdown' test would be better for pin pointing any problems .
Did you show NLM a sample of your oil?

[backfat1187]

The oil showed very little sign of contamination. Didn't notice at all when draining the sump. There was just a bit of pale gloop on the filter cover bolts. At that point I went straight for the rad. cap which is when it became more obvious I had a problem.

[eddydog]

My thoughts about the wear of the shaft. There is such an axiom. What was the first? Chicken or egg? In my case, it started with the appearance of antifreeze in oil. First a little. Continued to ride. Then more. The shaft has two plain bearings. Or at first there was a wear of the bearings, and the tip of the shaft with the rotor blades had a beating, because the wear on the shaft was from the rubber seal. Or, at first, the stuffing box began to skip, and because of this, the bearings began to wear out and the shaft beat (deviations) was increased. It is good that the shaft has no signs of wear. But you need to check for moving of the shaft tip, beating upwards, from left to right the tip of the shaft with the rotor blades. May be bearings has some gap. But these are my not professional thoughts.

[backfat1187]

Thanks eddydog. I will check for play in the bearings and put a dial gauge on the end of the shaft and turn the motor over to check for deviation.

[franky]

is it not just moisture from the inside of the cases? zx7r/zx10r/sp1 all use to show something that looked like the HG etc had gone, it just burnt off after running the bike for 10mins. Sure its not just temp differentials causing it?

[backfat1187]

Whole coolant circuit full of gloop. Not much water in the oil.

[backfat1187]

Pump shaft.jpg (70.8 KiB) Viewed 18053 times

So I've tried to measure the shaft deviation. Not easy to mount the dial gauge in a totally solid place. Just cranking the motor over by hand affects the reading.
However, the value is around 0.08mm at the shoulder nearest the small thread, and around 0.04mm where the seal lip sits on the shaft. That sounds a lot to me (based on precisely zero experience in these matters) so I'm really hoping someone can tell me otherwise. No apparent play in the shaft bearing and it feels perfectly smooth when turning the engine over.
Failed to do a leakdown test due to lack of 10mm hose adaptor. Grrr.
Spring seems to be approaching much more quickly now the bike's in pieces....

[fredlabulle]

I think there is an other reason that we find oil in water , on the right carter , in the conception one screw is missing to press joint between oil and cylinder water exhaus , there is a place for the screw in the joint but not in the carter , so it 's possible to place one and after there is less oil in the water
fb

[backfat1187]

Forgive me fb but I can't quite work out what you mean. I may need a little help.

[Ming]

I think Fred means that the right hand crankcase (carter) shows a screw hole on the design drawings which would improve the sealing. The joint has a hole in the appropriate position, but there is no screw. Does that help? Confused me a bit...

[MickeyMoto]

Le photo dit mille mots!

Be interesting to see where the screw goes and why it is not there...