How Much Damage Have I Done to My Engine?

paulrae

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The weather was seriously rubbish up here on Sunday, so decided it was oil-change time. Start the engine whilst moored to the marina berth, into gear @2000rpm and straight down below with the juke box on for a coffee whilst the engine warms up.

One cup of coffee (and a scone) later, up to the cockpit to stop the engine, only to hear the squealing of the overheat alarm. Immediately stop the engine and open the engine compartment. The oil was certainly warmed up, as was the whole engine block and compartment. Opened up the pump which did not have a single intact 'paddle' on the impeller - replaced. Changed oil and fuel filters and restarted engine. Halelujah, water emerged (after a slight delay), accompanied by a light film of what looked like soot in the water.

Now, I KNOW I should always check that there's water in the exhaust when I start the engine. Reliability breeds complacency, so I didn't on this occasion. I certainly will in the future.

The pump impeller has been replaced. I'm not seeing any other obvious signs of problems in the eegine compartment, but I know my luck won't have held out for that to be the extent of my misfortune this time.

So to my question. What other checks or investiagtions should I carry out to determine how expensive this mistake has been? The engine's a VP2030, by the way.
 
I hang a label on the ignition switch warning that engine seacock is off. Relic of my flying days checking pitot covers and elevator locks.
Agree it is worth checking for impeller bits. AT least the engine didn't seize, but I guess it didn't do much for the longevity prospects.
 
Have you found the missing bits of the impeller? If not, it's probably worth looking for them.

On Volvo 2003 the bits from a broken impeller migrate to the heat exchanger and blocks it, sod of a job to take off and clear, and new Volvo seals and o rings aint cheap.

I'm going to have an "I hate Volvo" T shirt made.
 
I winder how hot it really got?

The weather was seriously rubbish up here on Sunday, so decided it was oil-change time. Start the engine whilst moored to the marina berth, into gear @2000rpm and straight down below with the juke box on for a coffee whilst the engine warms up.

One cup of coffee (and a scone) later, up to the cockpit to stop the engine, only to hear the squealing of the overheat alarm. Immediately stop the engine and open the engine compartment. The oil was certainly warmed up, as was the whole engine block and compartment. Opened up the pump which did not have a single intact 'paddle' on the impeller - replaced. Changed oil and fuel filters and restarted engine. Halelujah, water emerged (after a slight delay), accompanied by a light film of what looked like soot in the water.

Now, I KNOW I should always check that there's water in the exhaust when I start the engine. Reliability breeds complacency, so I didn't on this occasion. I certainly will in the future.

The pump impeller has been replaced. I'm not seeing any other obvious signs of problems in the eegine compartment, but I know my luck won't have held out for that to be the extent of my misfortune this time.

So to my question. What other checks or investiagtions should I carry out to determine how expensive this mistake has been? The engine's a VP2030, by the way.


Assuming the engine has closed fresh water cooling then it would only have got to just under 100oC unless of course it had boiled dry so I don’t think the engine will be damaged however I would be concerned over the state of the rubber exhaust hose as it will have had no water going through it to keep it cool. The black soot may just be soot being washed off the walls of the hose but you might be advised to inspect the inside as these hoses can collapse and cause back pressure problems

Not sure if you have, but might be worth changing the oil as well.
 
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Assuming the engine has closed fresh water cooling then it would only have got to just under 100oC unless of course it had boiled dry so I don’t think the engine will be damaged however I would be concerned over the state of the rubber exhaust hose as it will have had no water going through it to keep it cool. The black soot may just be soot being washed off the walls of the hose but you might be advised to inspect the inside as these hoses can collapse and cause back pressure problems

Not sure if you have, but might be worth changing the oil as well.

+1

check

+water locks & traps, for shape change & any where the exhaust pipe travels through.

+ skinfitting on hull exit
 
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The overheat alarm is designed to go off BEFORE terminal engine damage, so the engine should still be basically sound. Do try and extract any errant bits of impeller though - good for long-term peace of mind.

The alarm could have been going off unheard for all the time it took to consume tea and scones :(
 
As said if the water in the fresh water cooling loop as not boiled and been lost no engine damage is likely.

The plastic and rubber components of the exhaust system very probably have been damaged

It could be wise to replace the rubber hoses even if they look OK externally
 
Yes you should find where all the mashed up impeller blades are. By the way which is the cheapest source for Volvo gaskets etc? Perhaps they are pennies inn Sweden? Seeing as a "Volvo" fuel filter is 20 quid when the real price is a fiver,there must be a way round the overcharging? Signed,a parsimoanious MD2010 user.
 
The only time I got a jolly to Sweden, my host told me he paid more in spare parts for his boat engine than a year's running costs on his car. As he said, "Buy a Volvo car but not their boat engines!"

Sadly every manufacturer seems to set their spares prices to match.

Rob.
 
Second thoughts... Once you've found all the missing impeller pieces, pull off the first section of exhaust hose as it's not designed to withstand flames! Usual construction is multi-layer and the inner layer can delaminate, causing a restriction or even a blockage. If that and the water trap is OK, then there is unlikely to be any effect further down the exhaust line.

It might help to treat the engine as though not fully run-in for a while - give it a chance to bed back in.

Rob.
 
Yes I wonder if the Swedish Navy use the home grown motors in the littoral defence forces or have they gone Jap? The ultimate stealthboat is the one you can't ****ing start.
 
catching impeller blades

Your only concern is damage to the exhaust as others have said, but at idle even that could have survived - but take it off t the exhaust elbow and see if it has de-laminated inside.

this impeller blades getting caught in the heat exchanger thing is not a new problem, us boaters have been putting up with it for years, isnt it about time we had a filter we could install between the pump and the engine to catch them - clear plastic perhaps so we can see them? anyone know of such a device?
 
Good idea,something similar to an inlet strainer,designed for hot water under pressure. Or even better an indestructible jabsco impeller!
 
VP 2030

The weather was seriously rubbish up here on Sunday, so decided it was oil-change time. Start the engine whilst moored to the marina berth, into gear @2000rpm and straight down below with the juke box on for a coffee whilst the engine warms up.

One cup of coffee (and a scone) later, up to the cockpit to stop the engine, only to hear the squealing of the overheat alarm. Immediately stop the engine and open the engine compartment. The oil was certainly warmed up, as was the whole engine block and compartment. Opened up the pump which did not have a single intact 'paddle' on the impeller - replaced. Changed oil and fuel filters and restarted engine. Halelujah, water emerged (after a slight delay), accompanied by a light film of what looked like soot in the water.

Now, I KNOW I should always check that there's water in the exhaust when I start the engine. Reliability breeds complacency, so I didn't on this occasion. I certainly will in the future.

The pump impeller has been replaced. I'm not seeing any other obvious signs of problems in the eegine compartment, but I know my luck won't have held out for that to be the extent of my misfortune this time.

So to my question. What other checks or investiagtions should I carry out to determine how expensive this mistake has been? The engine's a VP2030, by the way.

I have this engine. Finding the broken pieces of impeller is easy if you have good access to the front of the engine. Go straight to the hose on the front end of the heat exchanger (2 jubilee clips). Pick out the pieces with long nose pliers.

I also foolishly ran my engine without sea water cocks open for a while. The engine suffered no known damage.

Fingers crossed, you may've got away with it with only a big scare.
 
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