MD6A Problems - Water Gushing from Air Intake ???

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JordanBoon

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Hi threre i have a volvo Penta MD6A which we have just put into my Dufour 27 everything was going well, engine was starting, fuel system bled, when we try and run it with water and the whole machine starts leaking, water was pouring from the air intake, can anyone tell me what the problem is.

Thankyou Jordan
 
can anyone tell me what the problem is
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Major if not disastrous or terminal. Speedy action required to get rid of water from engine and change oil.

Anti syphon valve not functioning/ not fitted ?? Or just cranked with the water inlet open for long enough to flood the exhaust system and the engine with water

Head gasket? .. unlikely if it was starting and running OK

Exhaust manifold gasket ?
 
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VicS said:
Major if not disastrous or terminal. Speedy action required to get rid of water from engine and change oil.

Anti syphon valve not functioning/ not fitted ?? Or just cranked with the water inlet open for long enough to flood the exhaust system and the engine with water

Head gasket? .. unlikely if it was starting and running OK

Exhaust manifold gasket ?
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Vic....the way I read it he turned on the water ..as in tap...... then started the engine possibly ashore????????????????????????????


These engines should be started without a water supply if being tested ashore and then turn on the water to run them. Or use a bcucket to draw water from with the engine cooling pump.

The engine exhaust is used to evacuate the water from the engine overboard. If the engine is at rest and an external supply of water connected up then you will fill the engine and exhaust with water till it overflows from the inlet. The stopped pump will delay this but not stop it.

Luckily no damage just need to remove the mess from the sump and fill with fresh oil and run to temperature asap.
 
Hi guys yes i turned on the hose pipe that was fitted to the sea cock end of the water inlet pipe, then we stated the engine, do you think that we were pumping too much water into the engine that made it flood and hence came out of the air intake.
Thankyou very much guys for all the help
 
easiest way to ruin an engine, you have some work to do now very quickly, change the oil run engine, change oil again run engine, your looking to change the oil until you lose the mayonnaise effect you will get from the water which has been added to the engine,

BEFORE YOU START THE ENGINE, you also need to remove the injectors as you might end up bending a conrod if the engine is forced thru its cycle, with water in the cylinders.

In future only fill a bucket with a hose and let the pump suck the water up from the bucket, but only once engine has fired up...

You have a lot of learning to do, take it slow and ask on forum if your unsure, as a mistake of this type could have you losing the engine, only time will tell...

you have a lot of oil to buy so will let you get on and start on your oil changes....



Once you have changed the oil check that you actually have a impeller in the pump, by trying to pump water thru via bucket ..
 
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Yes Bilgediver is right. You turned the water on, the pressure easily forced its way past the water pump impeller, through the engine cooling system and then filled the exhaust system followed by one ( or both) of the cylinders via the exhaust valve(s)

At least it was fresh water so hopefully no terminal damage. But the priority must be to get rid of the water , change the oil and get some lubricant around every thing then get it running as BD says asap if not sooner.

Lucky you did not crank it against a cylinder full of water and bend a con rod.

If you run from a hose it is better put the hose into a bucket and suck the water up from there.

When afloat also remember that the same can happen if you crank for a long time. If the engine is difficult to start shut the sea-cock and only open it again once it has started.
 
Thanks very much for all this help, is anyone in the Portsmouth area that would be able to come and help me, obviously any help would not go unnoticed, My boat is at southsea Marina, i am going down there now to try and sort this problem out,
Also would it be possible to get a mobile number from someone or if you could call me in perhaps 45 mins that would be great on 07752 066 667

I am in big trouble i belive
Jordan
 
I've been helping Jordan with the engine. As has been stated, we run the engine up from a hose. My understanding was that so far he has not had the engine running. When he bought the boat a few months ago, for some reason the previous owner had taken the engine out of the engine compartment and it was sitting on the saloon floor. There is very very little compression on the engine (which I only checked yesterday after we had the water incident) so much so you can turn the fly wheel over with one hand. I've always wondered in the back of my mind why the engine had been taken out in the first place.
 
Drained the oil and it does not look too milky, got first fuel injector out but the second one is an absolute pain in the arse and will not come out. I shall do 2 oil changes and crank by hand when filled up again. Would i need to change the oil in the gear box, ill have a look at it.

Thanks Jordan
 
Re: the stuck injector. If you have removed the fasteners from it that's enough. Cranking by hand or electrically will break the stuck injector out with the force of compression(if it's got any! ;)). Crank it over with the injectors out to expel any water; when no more water comes out give it a squirt of WD40/diesel/dewatering spray of choice and crank some more. Refit the injectors(ideally with new sealing washers, or anneal the old ones if they are copper), bleed the diesel through and attempt a start.
 
JordanBoon said:
Drained the oil and it does not look too milky, got first fuel injector out but the second one is an absolute pain in the arse and will not come out. I shall do 2 oil changes and crank by hand when filled up again. Would i need to change the oil in the gear box, ill have a look at it.

Thanks Jordan
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The gearbox oil should not be affected as it is a different system if it has its own dip stick.

The injectors can be a problem if seized as they sit in copper sleeves which if moved may start to leak in the head. some times some judicious tapping can loosen them however it is best to try and jack against the sleeve top if possible.

You comment on the low compression. However remember that these engines do not develop much compression if just turning the flywheel by hand and not swinging it with the handle. The best way to be sure to get it started after drying out and refilling the sump is to squirt some oil into the inlet valves and then spread this around by turning the engine over decompressed by hand with the starting handle before starting. Don t turn on the cooling water till the engine is running.

Once you have run the engine you will have an idea of how good the compression is. The usual reason for low compression is problems with valves and valve seats which are easily fixed after removing the head(s).

It can be worth passing the heads to a local automotive engineer if the seats are bad as they can fit new seats and grind valves and seats to match.
 
Thankyou for the Help

Hi there guys, thankyou very much for the help, managed to get it working late last eveing, was an amazing sound as i was thinging the worse that a new engine was in order.

Saved me a pritty penny, so thankyou very much.

Engine is now working better than ever, starts first time without any 'easy start' which is supprising me, i have got one more oil change to do today and then putting the proper oil into it.

Now just need to find a mooring in the solent, does anyone know of anyone who has left for the summer who would be interested in sub letting their mooring.
Needs to be deep, got a 6ft fin keel
 
JordanBoon said:
Hi there guys, thankyou very much for the help, managed to get it working late last eveing, was an amazing sound as i was thinging the worse that a new engine was in order.

Saved me a pritty penny, so thankyou very much.

Engine is now working better than ever, starts first time without any 'easy start' which is supprising me, i have got one more oil change to do today and then putting the proper oil into it.

Now just need to find a mooring in the solent, does anyone know of anyone who has left for the summer who would be interested in sub letting their mooring.
Needs to be deep, got a 6ft fin keel
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Enjoy the sailing :D:D
 
ricky_s said:
Might be worth mentioning, this procedure is not the case for some other Volvo engines where water must be turned on first!
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Can you elaborate on that.

If a pressurised water supply is connected to the inlet and turned on before the engine is started there will always surely be a risk of flooding the engine ?

Likewise in normal service if the engine fails to start a lot of cranking can have a similar result ... worse this time because it'll be seawater
 
VicS said:
Can you elaborate on that.

If a pressurised water supply is connected to the inlet and turned on before the engine is started there will always surely be a risk of flooding the engine ?

Likewise in normal service if the engine fails to start a lot of cranking can have a similar result ... worse this time because it'll be seawater
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I have a volvo penta 5.0 V8, with a connection for a hose, the manual says switch on water then engine.
 
But what happens if you don't start the engine immediately or if it fails to start?

If the exhaust system is designed so that it cannot fill and then flood the engine that is fair enough.

Trouble with small yacht engines is that the cooling water is usually injected into the exhaust system immediately downstream of the exhaust manifold and the system usually includes a swan neck before the final outlet. It then relies on the exhaust gas flow to discharge the water from the system. If the water is on and the engine is not running then what happens is exactly what has just happened to the OP. Hence the advice not to turn on a pressurised water supply until the engine is running or preferably to use the hose in a bucket method.

What engine do you have. It would be interesting to look up the details.
 
VicS said:
But what happens if you don't start the engine immediately or if it fails to start?

If the exhaust system is designed so that it cannot fill and then flood the engine that is fair enough.



What engine do you have. It would be interesting to look up the details.
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Not sure if the water would just go out via the manifold, i'm no engineer.

The engine is a 2005 5.0 GXi-F. I downloaded the manual from the Volvo website.
 
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