Water in engine?

Csail

Csail

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Just had a survey on the boat and it said water in engine? I couldn't read the full survey as some chap wanting to buy the boat payed for it. So what are the likely causes. Its a Thornycroft T95 with a few hundred hours on it and fitted with anti syphon valve. Must admit that recently it has been puffing out white smoke or steam on start up.
 
Water in the engine- lub oil will turn creamy/ grey in colour.
Causes- head gasket / oil cooler tubes leaking/ exhaust manifold cracked/ salt water pump -leaking seals... lots more possibilities..
 
What does the oil look like?
If there is water in the sump the oil will be emulsified when hot.
There are only two ways water can get in; through a bust head gasket or back-flow from the exhaust injector and if the T95 is the same as my T90 that is unlikely.
FWIW my T90 has emitted white smake/steam for a few minutes every time it is started and always has done.
 
Defective antisyphon valve? They need cleaning from time to time. Head gasket?
 
If it's likely to become an issue in selling the boat I would ask the surveyor for his evidence before settling for an expensive repair. Taking the filler cap off will sometimes reveal emulsified oil inside the cap or in the rocker cover but this is often simply condensation. A couple of hors of hard running will usually clear it.

If oil on the dipstick is emulsified than you will need to look further, along the lines already suggested.
 
I have no idea what he means, the oil is bang on dipstick level and golden colour. No creamy stuff in the rocker box so what is he on about? The anti syphon valve is fine too.
Bit fed up as i lost a sale from it and can't buy the next boat now.
edit.... also when i asked the surveyor if the boat was fine to use he said yes but surely if he wrote on the survey about water in the engine it is not ok to use?
 
Just a suggestion here but when you say "just recently it has been puffing white smoke on start-up" well.....just recently has been cold, damp, wet at times, it's called WINTER! What I mean is, if you've just started up for a short time for a battery charge it could quite simply be that the engine did not achieve enough warm up heat to dry out previous condensation before you added another load to it. I suggest you give her a good run to get it really hot and then try a start the next day after it's cooled down again before you allow panic to set in.

Frankly, I think you are spoilt, if all you have is a bit of white smoke/steam on start up, I get the full spectrum colour effect when I start my old Thorneycroft after a lay up, plus a nice rainbow on the surrounding water. Boats all around dissappear in the murk, the BBC issue a fog warning and everything on the M25 goes back to a crawl! When it warms up properly all these interesting side effects dissappear - quite boring really!
 
'Water in the engine- lub oil will turn creamy/ grey in colour.
Causes- head gasket / oil cooler tubes leaking/ exhaust manifold cracked/ salt water pump -leaking seals... lots more possibilities.. '

Including cracked cyl head or block due to inadequate anti-freeze. Was your engine fully protected against sub zero temps?
 
White smoke on starting is perfectly normal. Steam is a bit odd if you have a wet exhaust. It's not like a car exhaust. In the exhaust elbow you have cold water injection that should condense any steam which would not normally go beyond the muffler. If you are seeing steam in the exhaust it might suggest that you haven't got enough water going through the injector in the elbow.
 
<<<< If you are seeing steam in the exhaust it might suggest that you haven't got enough water going through the injector in the elbow. >>>>

Or you have a Bukh 20 /forums/images/graemlins/wink.gif Renowned for steaming, although I suspect the cause may well be as you say. The 'gas poker' water injector behind the flywheel has only a few quite small holes, which frequently salt up.
 
[ QUOTE ]
I was told that Bukh 20 cooling water comes out very cool and that is why you can't heat a calorifier through one?

[/ QUOTE ]The water injection into the exhaust is always cold - straight from the sea - and goes out with the exhaust via the muffler (or separator). This has nothing to do with heating your domestic hot water in a calorifier. The calorifier is normally heated from a feed from the engine's fresh water cooling system that is thermostatically controlled to over 70C. I have heard of people with raw water cooling taking the hot raw water return into the calorifier. It all depends on how hot the return water gets in your engine and that depends on the power setting, thermostat and water flow (and bypass rate). I would imagine that the salt would be pretty harsh on a calorifier coil? It has been done, though, and you can search here on YBW or have a look on Westerly Owners' - several of them did it a few years ago.
 
[ QUOTE ]
We have a fresh water cooled engine, so don't know how the seawater systems work.

But on a salt water cooled engine, would you not have a heat exchanger to have a fresh water circulation which goes through the calorifier?

[/ QUOTE ]A fresh water cooled engine is just like a car engine. It has a header tank, a thermostat, a water pump and instead of a heater it often has a hose going off to the calorifier, to heat the domestic hot water.

In a car, however, the waste heat from the engine is disposed of by a radiator and fan. That's neither convenient nor the best way to do it on a boat, which by definition is floating in water. In a boat, sea (or river/lake) water is pumped up by a second pump - the raw water pump. That is passed through a heat exchanger that keeps the temperature of the fresh water cooling system at the correct level. In a wet exhaust system some water from the raw water pump is fed to an 'elbow' on the exhaust immediately after it leaves the engine cylinder head. Before the elbow, the exhaust gasses are very hot and the volume of gas is high. This would destroy any rubber or flexible fittings and it is difficult to silence a dry exhaust on a boat. So water is injected into the very hot exhaust gas right by the engine. This decreases the temperature and reduces the volume of gas, cooling, and silencing. The mixture of cool gas and cool water usually goes to a muffler box where the pressure builds up until it can blow out a blast of water. That's why you hear a 'shoosh......shoosh' noise from a wet exhaust. If the raw water supply fails (impellor or weed in filter) then there is no water in the muffler box and you hear the exhaust coming out like a car engine. It is very hot and unless you stop the engine quickly, you will ruin the exhaust hose (can be very difficult to replace).
 
Not sure you are right about the raw water being cool when it is injected into the elbow. It has just come from either cooling the engine if it is raw water cooled or cooling the fresh water through the heat exchanger - and in my experience is hot! because that is what it is doing, taking heat away from the engine. Many people run calorifiers off raw water, but generally it is cooler than fresh water systems - but still hot.
 
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