MD22L Water contamination in the oil

[Talulah]

In the last year one friend has bought a Moody 38 and another a Najad 37. Boat are fitted with Volvo Penta MD22L
Boat boats are mid 90's.
The owner of the Moody ordered a new engine (Yanmar 4JH5E) at the London boat show. He wasn't confident about the MD22 and wanted a new engine. (Money was not an issue.) The engine is due to be fitted in March.
The Najad owners not knowing the history of their engine decided to have an oil analysis done. The report came back fine except in one area where it was marked as 'critical'. This was water contamination in the oil. Nothing to see by the naked eye.

So having had the report and researching it they came across this article:
http://www.diecyde.com/index.php?page=volvo-penta-md22-overhaul

I was gobsmacked to read it. In true PBO style the owners on that site did a fantastic job of repairing it. Clearly they had the facilities and skills to do it.
My advice to the Najad owners is to now take off the exhaust elbow. As well as checking the elbow itself check the heat exchanger for the problem highlighted in the article.
I wouldn't be surprised if they found a pin prick of a hole.
It may be that having the oil analysis done they've caught the problem early enough to save on buying a new engine.
Now how many other MD22 owners are there on these forums with an engine of similar vintage? Time to inspect your heat exchanger?

 

[NUTMEG]

Brilliant. Something else for me to worry about :-(

 

[Bobc]

They're a good engine and go for ever, but the bits VP bolt to them are carp. I had a hole in the aftercooler, and have had some chorosion on one of the heat exchanger flanges (which needed welding). The heads are also prone to chorosion on the edges of the water blanket, which can let water past the head gasket into a cyliner without blowing the gasket.

It's quite a simple job to remove and strip-down the heat exchanger and the head, and that would be where I would start to look rather than buying a new engine. You can get any chorosion on the head built-up with weld, as you can with the heat exchanger. If you take the head off, get it skimmed though, because they can warp.

 

[<152587>]

Before you start ripping the engine apart, have the fresh water system pressure tested. If the oil tested showed no signs of emulsion (like grey / white double cream) the water content is very slight and may be present by way of condensation.

 

[Bobc]

Before you start ripping the engine apart, have the fresh water system pressure tested. If the oil tested showed no signs of emulsion (like grey / white double cream) the water content is very slight and may be present by way of condensation.

Very true, and very sound advice.