how easy it is to sink your boat

BartW

BartW

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a couple of weeks ago, during our holliday's in Croatia,
we went stream up a local river.

we noticed there was a lot of dirt on the water surface from the thunderstorm the day before, but we didn't give this much attention.

30 minutes later when we were at full speed in open sea, 5 miles from shore, (80m deep),
I noticed temp on SB engine was over 100 deg.
the P engine was at normal temp 85deg.

trottle down to idle (to cool the engine) but after a minute or so, no change

I stopped SB engine, opened the engine bay, and discovered
THE BILGE WAS FILLED WITH WATER,
each engine was 10cm in the water,
everything in the enginebay , battery's, electronics, fuel filters, was wet from salt water spray

immediatly instructed swmbo to limp on one engine towards a close island, while I emptyed the bilge.

Quite fast I discovered that the hose from the water pump to the raw water filter was disconnected.
The filter was full of dirt,

so while the waterpump continued to put pressure, that hose must have been disconnecting, so the bilge quite easyly filled up with sea water.

after emptying the bilge, cleaning the filter, reconnecting that hose, and fixing the hose clamps a little stronger, also on the other engine, we were very lucky that both engines started again.

later in the harbour I cleaned the engines an all parts in the engine bay with still water,
I believe that we were very lucky that the water did not reach higher,
first of all for no damage to engine's nor parts
secondly for not sinking the boat.

here is a picture of the water filter, (SB + P)
you can see how much pressure the pump has put on this (SB) filter while it was full of dirt.

soryy no pictures of the incident, too much stress

I am just wondering if I will not get problems later with certain parts, due to that salt water,
fe. Starter motors ?
 
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Quite scary! The sea water pump will fill the bilge quicker than most bilge pumps could empty it. However, if you have an auto bilge pump with a float switch, most are wired such that a telltale light comes at the helm position, this would hopefully give you warning of the bilge filling before the engine overheat alarm triggered.

Eddie
 
Wow, you are very lucky to get out of that with only your pride dented!!

I must admit to switching on our bilge pumps for a few seconds every now and again whilst at sea and looking over the side to the outlets just to check nothing is being discharged.....I keep my bilges dry, so hopefully this will show up any problems asap!!!!
 
Blimey! Glad you didn't suffer any more than that.

I would think yr engine compnents will be perfectly fine if you rinsed the salt away very thoroughly. I'd spray some WD40 or similar, too.

I'm confused about your plumbing. Are your raw water filters downstream of the raw water pumps? From what you write, it sounds like they are. That seems strange to me. I'd expect the filters to be upstream of the pumps. Then a blockage at the filter would put vacuum, not pressure, into the pipe twixt pump and filter, and make it LESS likely to come off. So I'm struggling to understand your analysis!

As said above, you should definitely fit bilge alarms with loud hooters

Anyway, glad it was all ok in the end
 
On some older volvo engines the plumbing put the raw water filters downstream of the pumps. I had AD41's once which were designed this way. If the strainer tops weren't really tight this produced a fine mist over the engine belts which, of course, tended not to last very long. A bit mad you might say, unless you happened to be a manufacturer of engine belts.
 
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benjenbav said:
On some older volvo engines the plumbing put the raw water filters downstream of the pumps. I had AD41's once which were designed this way. If the strainer tops weren't really tight this produced a fine mist over the engine belts which, of course, tended not to last very long. A bit mad you might say, unless you happened to be a manufacturer of engine belts.
Click to expand...

Blimey. So the pumps and impellers were not protected from all the craap sucked up out of the sea. The filters only catch the crud AFTER it's been through the pump. A kind of shutting stable door after horse has bolted genre of lousy engineering!
 
benjenbav said:
On some older volvo engines the plumbing put the raw water filters downstream of the pumps. I had AD41's once which were designed this way. If the strainer tops weren't really tight this produced a fine mist over the engine belts which, of course, tended not to last very long. A bit mad you might say, unless you happened to be a manufacturer of engine belts.
Click to expand...

I've just had this exact scenario on my older AD41's, my own fault, I didn't refit one of the strainer caps quite correctly which left a fine jet of seawater on to the belts. Now need to replace all of them and repaint all the pulley wheels. Interestingly high temperature and bilge pumps kicking in was the clue something was amiss!
 
jfm said:
Blimey. So the pumps and impellers were not protected from all the craap sucked up out of the sea. The filters only catch the crud AFTER it's been through the pump. A kind of shutting stable door after horse has bolted genre of lousy engineering!
Click to expand...


thats how it is, and this is not an older engine, a D3 is the newer generation,
so yes poor engineering.
coincidently today I read that volvo has launched a new generation D3's
with full electronic controll, to cope with the joystick steering.... ,more HP options, and some cosmetic changes
I wonder if they have changed the cooling cirquit layout

The boat has an automatic bilge pump, and this was working, but could never pump out the volume of water coming in from the raw water pump.

This incident made me decide to have an audible alarm (horn) on the floater switch in de bilge.
alarm lights are of no use in sunshine

yes a very scary moment, luckyly with a happy end. :)
 
Wow! Yes, it would be great if they changed the pump/filter set up.

For your bilge alarm, you can get them with a delay. In other words, the klaxon only sounds if the bilge pump has run for >15seconds continuously. Then you get no alarm for small amounts of bilgewater. This has been standard fit on fairline for about 10 years
 
jfm said:
Wow! Yes, it would be great if they changed the pump/filter set up.

For your bilge alarm, you can get them with a delay. In other words, the klaxon only sounds if the bilge pump has run for >15seconds continuously. Then you get no alarm for small amounts of bilgewater. This has been standard fit on fairline for about 10 years
Click to expand...

Good idea, never seen this on smaller boats,
alway's have some water in the bilge when cleaning the deck...
I guess at FL this delay it is part of the electric cirquit and alarm systems,
so nothing you can by from the shelf ?

but no problem we will make a small electronic device.

thank you for the tip !
 
Re. future problems

Yes, I had a starter motor die on me because of corrosion - probably caused by my leaving off the top of the raw water strainer once. Very embarrassing.
Couldn't restart the engine after drifting a while some 4 mls off the coast. Had to be towed into harbour by the lifeboat. Very, very, embarrassing!!
 
Future problems

BartW, I had a similar problem many years ago in a Sealine, caused by a faulty connector in the calorifier circuit. Even after repairing the fault, we were still taking water, in real danger of sinking and had a long way to go.

I won't bore you with the details, but we got the boat back and lifted out fast.

The engine room was a mess. Everything was soaked and covered in oily soot. I spent the next day amongst the engines in my underwear with a paraffin compressor gun cleaning it down. The whole length of the boat bilges was contaminated.

However, the engines and electrics suffered no damage. I think that provided you clean up thoroughly and pay attention to detail, you will probably have no problems.
 
jfm said:
Blimey. So the pumps and impellers were not protected from all the craap sucked up out of the sea. The filters only catch the crud AFTER it's been through the pump. A kind of shutting stable door after horse has bolted genre of lousy engineering!
Click to expand...

All Volvo sterndrive engines have the filter after the seawater pump!
 
Filters upstream of the pump are designed to prevent broken impellors entering the coolers, however you probrably wouldnt break so many if the were protected by a decent filter first, also not much use when putting anti freeze through at winterising.
Perkins sabre had the best idea as they have a small impellor catcher filter after the pump and you have the main filter before.
The best warning you can get for restriction in raw water circuit is an exhaust alarm as it usually goes off before the damage is done.
 
whisper said:
Yes, I had a starter motor die on me because of corrosion - probably caused by my leaving off the top of the raw water strainer once. Very embarrassing.
Couldn't restart the engine after drifting a while some 4 mls off the coast. Had to be towed into harbour by the lifeboat. Very, very, embarrassing!!
Click to expand...

do you remember how old the engine was when you had this problem ?
I have a feeling that most sterndrive inboard engines will suffer one day or the other, from starter motor failure, as they are usually in a wet and salty environment,
unless your engine compartment is very well closed, and you keep it perfectly dry and clean
 
aquapower said:
Filters upstream of the pump are designed to prevent broken impellors entering the coolers, however you probrably wouldnt break so many if the were protected by a decent filter first, also not much use when putting anti freeze through at winterising.
Perkins sabre had the best idea as they have a small impellor catcher filter after the pump and you have the main filter before.
The best warning you can get for restriction in raw water circuit is an exhaust alarm as it usually goes off before the damage is done.
Click to expand...

the perkins idea is indeed very good,

but why doesnt Volvo put a filtering grid on the water intake on the drive ?
easy to do,
easy to see if it is dirty
and easy to clean
 
BartW said:
do you remember how old the engine was when you had this problem ?
I have a feeling that most sterndrive inboard engines will suffer one day or the other, from starter motor failure, as they are usually in a wet and salty environment,
unless your engine compartment is very well closed, and you keep it perfectly dry and clean
Click to expand...

Boat was 4-5yrs old when I had my "moment". Failure came 2yrs later.
 
How close did the sea water get to the starter motors?

Are they reasonably easy to get to? Perhaps for peace of mind take them off for a closer inspection and open them up.
 
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