Water in Velvet gearbox

[BiG]

Hello,

I am currently sailing on my motorsailor, equipped with Ford Lehman 2715E and a Velvet drive (not sure which one since the label is gone, I would say the 72C). After 5 days on sea, my family and I are slowly reaching our destination, the Canaries, 40 nm away, at a speed of about 0.5kts...

The small problem is that, while sailing without the engine running, I discovered a lot of milky oil, really milky, like mayonnaise, in the bilge. It appears to come from for the Velvet drive [see picture], precisely from the breather. Unsurprisingly, the stick is full of milky oil as well.

I know this means there is water in the oil. I very strongly suspect the heat exchanger, since water come out from the oil system when I unplugged it.

My first concern is to be able to use my engine when arriving in the marina, so for about 10 minutes, without creating too much additional damage. My second concern will be on repairing that, but I would appreciate if we can focus on the first concern for now, since we have been on the sea for quite some time now and we just want to reach the marina safely and as soon as possible.

To this end, my idea is to remove as much "mayonnaise" as possible and replace it with the least bad oil I have. I first used a syringe in the control stick hole and then flushed the exchanger. This spilled milky oil everywhere, but remember, I am currently sailing. I saw drops of water leaking from the oil circuit in the exchanger, confirming the most likely cause: defect in the exchanger.

I have 3 oils on board : Mobil ATF320 for hydraulic steering system, PBM SAE140 and engine oil 15W40.

My idea is to add some 15W40 in the gearbox, then start the engine to flush a bit more mayonnaise through the exchanger hose, then add again 15W40. This will not stop the water from entering the Velvet drive but I hope I will be able to use the engine for the maneuver.

Does that seem reasonable to you? Do you think it could run the engine more than 10 minutes like that (there is no wind so we are currently moving at 0.5kts, which is not fun at all)?

I am also considering taking out the exchanger, identify the leaking cylinder and block it with some cone shaped wood.

Any useful comments will be very much appreciated, thank you!

 

[rslifkin]

If you can, just bypass the oil cooler for now by looping one line back to the other port on the trans. Keep an eye on trans temp when you run it (max safe temp is 190* F), but for a few minutes of maneuvering it shouldn't get too warm. For a longer run you'll need to keep a close eye on the trans temp and probably run slower than you normally would.

Once you have the cooler bypassed, get as much of the mayonnaise out as possible. Use the Mobil ATF if you have enough, as that looks like it meets the specs for the trans. If you don't have enough, use the 15W40. It's not ideal, but it shouldn't hurt anything.

If you can manage a temporary repair on the cooler that's good enough not to leak that's also a viable option.

 

[SIBERNUT]

My VD has a drain plug stb side.

 

[SteveK]

In your situation I would also bypass the heat exchanger, remove and replace the milky stuff. Run the engine for as long as needed and then replace heat exchanger and flush trans by input into one hose and out the other. Run it and flush again until only clean oil comes out)
Then decide if a trans rebuild should be done.

 

[BiG]

Thanks a lot for your answer. I managed to identify the leaking tube by putting water in the oil circuit of the exchanger: it made the milky oil get out of one tube, see picture. So I made two cones out of wood to plug both ends, and when I blow with my mouth, no air gets out now (contrary to before). It is not the best watertightness test but might get me extra engine running time for my arrival.

I appreciate the bypassing idea as a backup solution.

I will look for the drain plug right now, but have not seen it in the documentation.

 

[BiG]

It is really difficult to remove the milky stuff. By flushing through the hoses, you mean with some external pump?

What works best for now is to run the engine and disconnect the hose between cooler and trans, that spits milky stuff. But that forces me to run the engine, at least in neutral, which slightly rotates the transmission axis. I did it a bit, while monitoring the temperature of the hose, which has not exceeded 120F (50°C).

Do you think I should add oil, wait one or two hours for cooling down, and repeat the process? I am also afraid that the new oil becomes milky due to the residual water, also.

Regarding the bottom drain, @SIBERNUT, are you referring to this square bolt? From the doc, it seems to be the location for the cooling hose, which is not the case on my trans.

 

[SteveK]

That drain plug looks to be in a good position. Usually they expect you to you a dip stick hole extraction pump.

 

[BiG]

I only have a manual syringe onboard, and it is not very good at extracting the milky oil.

Upon kind confirmation, I will open the square bolt to drain. Actually I already tried but it was tightly screwed and I did not insist.

Thank you all

 

[mvweebles]

Question for the better mechanics here: would flushing with diesel help make the mayonnaise extraction? OP has plenty of excess diesel and it's thinner viscosity might flush better

Peter

 

[rslifkin]

Question for the better mechanics here: would flushing with diesel help make the mayonnaise extraction? OP has plenty of excess diesel and it's thinner viscosity might flush better

Peter

I'd expect it would, partly because it's thinner, partly just because you'd be able to do more flushing. I'm not sure if I'd want to try running it to flush the cooler lines with diesel in there though.

 

[SIBERNUT]

That's the drain. If'n it was me, id drain it, fill w #2 (FULL TO THE TOP, not just dipstick mark), then drain it. Repeat. See what comes out after that. If pretty clean, id say good to go. There is a particular chant while doing so , but i cant remember it.

 

[mvweebles]

There is a particular chant while doing so , but i cant remember it.

Perhaps a prayer to St. Jude, patron saint of lost causes. Often invoked in desperate times.

Peter

 

[BiG]

That's the drain. If'n it was me, id drain it, fill w #2 (FULL TO THE TOP, not just dipstick mark), then drain it. Repeat. See what comes out after that. If pretty clean, id say good to go. There is a particular chant while doing so , but i cant remember it.

I managed to unscrew the drain at the bottom starboard. This was indeed a great idea, thank you.

Next steps: find a new exchanger or fix it, then follow SIBERNUT's advice (except for the chant) by filling to the top until it is clean. Maybe with diesel first without starting the engine, then with 15W40 or appropriate oil if I find, now that I arrived safely on land.

 

[SteveK]

Now that you are back on land, maybe look into a flush like suggested using the two hoses that go thru the heat exchanger. My thinking is that is forcing the exchange thru rather than gravity feed of new oil which may bypass some orifices.