Daft engine question

Impaler

Impaler

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OK, I know I should know. I have a Yanmar 1GM10 only aquired this year. Suddenly I noticed puffs of what looked like exhaust and sometimes water squirting over the port side. I found a port in the hull near the fuel tank vent. It only puffs and or squirts on start up. I can't find any pipes inside as it's all a bit crowded. Any clues? Obviously I aint an engineer.
 
Inside an engine there are tiny elves. They all sit on bicycles and pedal like mad when you engange the drive.

But on startup, you have just wakened them from their sleep, and they need breakfast. The smoke you see is from their stove chimney while they stoke up the oil burning stove to make the tea. Then, after a quick slew of tea, they do their dishes and clean up. Thats the water you see going out the side when they pull the plug out of their sink. After having a decent start to the day they are all ready to do you bidding, and will provide you with all the propulsion you need, pedalling as fast as you ask via that message sending indicator some people call a throttle.
Did you know its called a throttle because when you adjust it a notice comes up in the pedalling room for the elves on duty pedalling that says "go faster or I'll throttle you", or "go slower or I'll throttle you"?
 
You forgot to mention that the main reason that an engine won't start, usually after some hamfisted repair is that in the process the elves have been allowed to escape or alternatively that Lady elves have got in!

My experience in more serious cases that a troll has got in.
 
Sounds very serious to me. Puffs should definitely be confined to the starboard side. What kind of port did you find in the hull? I like a drop of Cockburns. Watch out for the squirts though, might get some in your pipe.
 
Assuming its not the main exahust you are talking about I suspect it could be the drain from the anti syphon valve. It may be sticking open and hence the small discharge of water which ends after a short while as it closes.

I'm sure a Hunter owner on here will tell you where to find the valve.
 
If you like Cockburns, you'll probably like these

sorbits.jpg
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The port side discharge comes from the top of the anti-syphon loop downstream of the pump and before the cooling water gets to the engine. When the water pump is new it stops any water flowing past it but as it wears in service water will flow past it. It will flow back into the engine if the underside of the mixing elbow is at or below the waterline. To prevent this, a siphon breaker ( aka anti siphon valve, vented loop ) is fitted. I would check the pump impeller and, of course, the hull valve and inlet strainer, but it's probably time to look at the water pump.
 
Can you send me some of your 'tobacco' please?

********************************************

Not tobacco.......good quality tarred and shredded rope.

Seeing it was xmas they preferred to make a joke rather than tell you the bad news.....

The port you see the puffs from is no doubt connected to an anti syphon valve...One learned fella says how on his boat this is between the pump and the engine...Now if yours is like this I would be very concerned cos I would ask are are those darn Elves puffing their wacky backky out of a port here in this position.....Could mean a possible problem developing... Or the puff is just ordinary air then no problem.

If the vented loop is fitted between the engine and the exhaust water injection point then yes it is possible for exhaust to puff out here till either the water flow establishes or the vented loop anti syphon valve closes....It is not that usual to have an over board discharge from an antisyphon loop fitted with a valve...but normal to have an overboard discharge with an antisyphon loop with no valve...however in this case the water does NOT stop but pees out of the tell tail all the time the engine is running.

It would be nice if you could ask the elves where your anti syphon loop is fitted and is it exhaust or air coming from it so we can either commiserate on your expensive misfortune and offer all sorts of well intended duff advice on how to fix.....or just confirm that the elves can go on puffing adinfinitum.

The advice will improve in quality as we head into the NEw Year and sober up /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif
Gooday MAte
 
The elves only puff and squirt for a few seconds on starting then they stop and she rumbles away quite happily with water sluicing from the exhaust. New impeller, no overheating. May call an expert to have a look.
 
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