VP drive failed again ... 3rd replacement

[Tafflad]

I posted previoulsy about corossion issues requiring replacement of VP drive.

280 C-N. Corrosion

Volvo Penta drive exchange. (Detailed in previous post) Finally after 14 months of waiting my new DPS drive has been fitted. The ‘old’ one had severe corrosion, I had spotted this initially on bearing carrier, and that is what I reported in Aug 2021 First dealer took boat in, after 5 weeks of...

forums.iboats.com

I have a VP 280 C-N engine with DPS drive, posted here of serious corrosion on the drive with is on a non-moored boat.

VP replaced it under warranty ….. after only 5 trips out the paint was corroding badly again. At any corners or at bolt holes, corrosion was under paint like a spiders web various photographs and VP even sent their Product Specialist to my house to inspect the drive.

Initially it was assumed some form of paint application process issue … they were to paint and refit.
Today they fitted an other new drive, the third one, and boat only done 110 Hrs.
This time the drive is the new OCEANX variant.

Web site quotes “the durable titanium-ceramic OceanX coating, which is applied using a state-of-the-art electrodeposition process and covers the entire drive assembly, makes the Volvo Penta drives four times more resistant to galvanic corrosion."

Very strange that it corroded when out of the water.
VP confirm all bonding is 100% correct, and added that anodes only protect when in weather so no effect when out.
I fresh water flush on muffs and wash outside after every use ….. unsure whether I should look to spray and de-watering lubricant (like WD40) or similar - have asked VP for advice.

 

[Scott Danforth]

use a can of boeshield or fluid film and hose down everything but the anodes. That will slow corrosion from starting.

I wonder if VP changed their paint process a while back for VOC reasons?

 

[ejnichol]

Any pictures of the corrosion. Would be interesting to see how bad.

 

[Tafflad]

Any pictures of the corrosion. Would be interesting to see how bad.

This is what drive went like after about 15 Hrs use ... in salt water, flushed with Fresh water until up to temp, then Salt Away, then washed & rinsed.
VP advised use to send of season , then they would resolve.
The inspection report said:
The corrosion we are seeing on your drive is happening because of an anode becoming passive, so the propellors should have no bearing on this. There should also be no reason for extra anodes as if the become passive they to, will have little effect.
The anodes will only protect the drive from corrosion when the boat is in the water, out of the water the reaction of the galvanic cathodic protection cannot happen as there is no circuit to be made through air as opposed to water. So, any corrosion that is started when the boat is in the water will continue once the boat is lifted albeit at a reduced rate.

The Anodes becoming passive as they are dry - boat not stored in water.

View attachment Port 2.jpgView attachment Starboard 1.jpg

 

[Mc Tool]

What a bloody shame , that is an awesome looking piece of kit......even standing still.
I think that there must be issues with the surface prep.
I hope you get it sorted

 

[Lou C]

That sounds like some VP mumbo-jumbo making an excuse for a flawed painting process.

 

[Tafflad]

On both times it failed it started on the sharp corner where the bearing carrier is (as in picture)
My question was if the large amount of stainless in the DP set up caused excess electrolytic issue.
There was focus on the bonding, but all proved correct.
I think the sharp corners had thin paint and/or possibly paint prep problems.

i am glad VP have good customer service .. 3rd drive is a big cost to them.
the spec on OceanX seems very good - quote from review:
’Volvo Penta uses a titanium-ceramic coating for exceptional corrosion protection. It’s flexible, so less prone to flaking and chipping off.’

 

[Tafflad]

use a can of boeshield or fluid film and hose down everything but the anodes. That will slow corrosion from starting.

I wonder if VP changed their paint process a while back for VOC reasons?

Not aware of Boeshield, looked on line it says it leaves a wax like finish, you advising this as a one off job, or before each use ?

Maybe similar to ‘Corrosion Block’. (Marine ver of ACF50)

Marine - ACF 50

Marine - ACF-50, Anti-Corrosion Formula, is a state of the art, anti-corrosion/lubricant compound, that has been specifically designed for the Aero Space Industry

www.acf-50.eu

I have that, I could use.

 

[Scott Danforth]

once every few months

 

[Mc Tool]

I use CRC Long life spray now ( used to use crc 6-66 marine) ,I spray it on after the post fishing washdown . I also use the long life on all my stored ( mothballed and not used .303's) rifles and shotguns . I leaves a goopy coating after a few applications. I like it because it works and it doesnt run off into stocks.

 

[Tafflad]

I have asked VP last year and they did not recommend any sprays.
They have been very good at providing new drives …so don’t want to compromise any warranty position.
it does seem logical to use something.