Water in Oil but Pressure test OK!

[kennyh]

Hi all

My VP DPH leg showed signs of water in the oil, but a pressure/vacuum test showed no leak!

Now I had lost a hub on one of the duo props and the props were grinding together.

Is it possible that the water in the oil was due to a transient issue caused by the hub failure, and once the prop was removed that the seals re-sealed?

I’d welcome your thoughts.

 

[DavidJ]

Those legs are so highly stressed that 100% oil effectiveness is essential so strip down I’m afraid. I’d be surprised if you have alternative advice….but you never know!

 

[Momac]

My VP DPH leg showed signs of water in the oil

What signs?
Was the drained oil milky throughout it was it just a tiny bit of mayonnaise?

 

[oldgit]

Fishing line or similar has been claimed to allow water into the gearbox in the past.
Take a chance and trust the test, put it back in and then spend the season wondering ! or replace gearshift/propshaft seals plus new exhaust and U/J gaitors.
If it lets go halfway through the season it will get expensive.
Think you already know the answer. ?
Much of the expence/time and trouble is getting boat ashore, new seals and labour a small proportion of that, those seals cost pennies and mebbe a short days labour from somebody who knows what they are doing.
That super duper synthetic oil has got to be changed regardless.

 

[kennyh]

The oil was slightly discoloured throughout, but no water layer / water separation.

 

[kennyh]

Fishing line or similar has been claimed to allow water into the gearbox in the past.
Take a chance and trust the test and put it back in or replace gearshift/propshaft seals plus new exhaust and U/J gaitors.
Think you already know the answer. ?
Half the expence and trouble is getting it ashore and the seals and labour only represent a small proportion of that.

I had the leg in at a mechanic and they have advised that they have pressure tested and inspected and that no leaks have been found. They have cleaned it and refilled with oil and it’s ready for collection.

Perhaps I should go with it and lift towards the end of the season and test the oil before layup?

 

[oldgit]

Discolouration ie bit brownish and gearbox oil no longer gin clear is just normal.
Any milky oil and creamy foam is most probably water ingress and needs sorting.
Normally all the oil will be emulsified and no clear division ie water on top of oil.
Sound like you might be OK.

 

[Greg2]

Discolouration ie bit brownish and gearbox oil no longer gin clear is just normal.
Any milky oil and creamy foam is most probably water ingress and needs sorting.
Normally all the oil will be emulsified and no clear division ie water on top of oil.
Sound like you might be OK.

+1
That would be my view based upon what is described

 

[Portofino]

When you say “ lost a hub on one of the duo props and the props were grinding together.” In post #1 .

Could this cause transient vibration / wobble enough ONLY when running to comprise a seal ? = Water ingress = milky oil = passes a pressure test ??

You are not imaging water ingress nor is the engineer imagining his test results .

Makes no sense not to replace seal(s) .

 

[QBhoy]

Easy to nip the seals out of place after an oil change. Older 290 variants are famous for it