Marine Turbocharger

Sounds very much like the intake is injesting salt spray along with the air. Start by investigating filtration on the air inlet. Does it exist, could it be improved?

The root causes of the problem are

-poor efficiency of air filter to eliminate moisture from the air

-poor workmaship of material construction of compressor wheel

dsyamiqh,

There are a couple of possible sources for this intrusion.

Depending on the age of the vessel and the turbocharger, the source could simply be atmospheric in nature. I would hope this isn't the case, because a turbocharger should be swapped out periodically (somewhere in the range of 10,000 hours, depending on manufacturer's specs) well before this would be noticeable.

Another possible source could be a ruptured tube in the charge air cooler. Seawater intrusion in this case may not be possible, depending on the design of the engine (i.e. where the cooler is placed).

Finally, you may be getting the dreaded "used but good" replacement parts that some rebuild shops like to use. In other words, you may not have a problem, per se, except that you need to bring the hammer down on your contractors.

Regardless, if you're seeing seawater on the compressor side of the turbo, it may be a very bad sign of bigger issues. I would take a look at a ramdomly selected head (or heads) to see if the seawater is causing corrosion on the intake valves or anywhere else in the head and cylinder.

I hope this helps.

Good luck

Chief Chad

Dear Dsyamigh,

The type of problem indicated by you, that salt deposit on blowerside(compressor side)of the turbocharger does not happen normally.Turbineside of Turbochargers of Large diesel engine on board ships are normally fresh watercooled which in turn is sea water cooled. There is very little possibility of sea water or fresh water ingress to blowerside due to casing corrosion etc( as happens on the turbine side)of the T/Charger as there is no cooling casing in the blower area.

In a normal T/charger the air outlet from the blower side gets cooled in an air cooler which is sea water cooled, and this air enters the scavenge air manifold and then to the engine. There is no possibility of sea water going backwards to the blowerside,even if there is a leakage in the air cooler.

Only possibility is if the turbo chaging is a two stage type where in the air is cooled

in an intercooler before entring the second stage. I have only read about this type and have not seen such type.

You have not mentioned the type ,make and other details of the T/c where in you have faced this problem.
May be you shoud look in to what chief chad said.