Prestige 32 isn’t sucking water into strainer baskets

[timmy92]

I noticed last night when I turned the engines on that the water wasn’t coming out of the back of the boat. Turns out it wasn’t sucking in through the sea cocks into the strainer/engine etc. Has anyone encountered this before. Impellers seem ok. Boat is 2001. KAD300. New to this type of boat so all advice is greatly appreciated. Thanks 

[Charlie-Bravo]

First step, disconnect the pipe from the seacock with it shut off, then ease it open, water should gush in at quite a rate, if it trickles its blocked.
Blockages can often be weed or a plastic bag, or even a jellyfish sucked in there . sometimes you can blow the blockage out with a dinghy foot pump, but be prepared for the gush of water if and when it clears, plus have a bung and hammer to hand in case the valve refuses to shut ........ they choose their moments to mis behave, failing that, ramming a wire or such like through the valve might shift the blockage.

One last thought, if the valve is old, sometimes the handle moves but it doesn't actually open the valve, if you disconnect everything from the valve you can look inside it and see if it is opening ( keep the bung handy) . you can replace a valve whilst in the water if needed, but it takes a special silicone disc on a stick to block out the sea water whilst you operate, and the valve must be open to pass the disc on a stick ( the proper name being Seabung ) to the outside of the hull, and not an operation for the nervous types.

Good luck
CB

[rene460]

Hi Timmy, welcome to the forum, it’s a great place to find information about your boat from friendly like minded folk.

I don’t know what type of strainer is installed on your Prestige, but my SO30i engine water intake has a strainer with a removable top.  It’s mounted with the top just above water line.  I needed one of those oil filter strap wrenches to remove the top, which I did with the valve shut (in case it was not above the water line).  With the top removed, I could pour some water in from inside the boat, then opened the valve to watch it drain down, and found it was very slow for the pipe size.  I was not sure if it was a creature found a home or a plastic bag, so I poured in some bleach, that should make any creatures move away, and just in case, some hot water, then a cup of vinegar.  While most creatures can live in a wide range of conditions, they don’t like sudden changes, I tried to make things uncomfortable so with luck it would move away.

With the filter draining freely, I started the engine without dropping off the ropes, ran forward to check the propellor wasn’t badly fouled then reverse to send a good flow forward past the water intake.  I hoped this would remove a plastic bag that, if it was actually the problem, might have moved enough under the liquid pouring through the filter, but still enough in place to block when the flow was inwards again.

It was probably more than was necessary, but it cleared the problem, and I have not had it happen again. 

If your filter housing has a removable top, it’s not so scary as pulling the hose off the valve.

rene460

[timmy92]

Thanks guys - I've tried the basics .. but no joy. Put the hose through it and turned the engine on water is coming out the back but it seems "dirty" what comes out is similar to when diesel/oil is spilt in water very merky!

Not overly confident to do much more. I'll leave it to the mechanics ... jumped in the water & went underneath .. nothing seems to be blocking it .. fingers crossed its a simple fix!

[allan]

We had a similar problem on our P32 after cleaning the filter baskets. If you have the solid black water strainers, getting the solid black discs to seal and create a vacuum can be a pain. Close the sea cock, fill with water until the strainer is full,get someone to start the engine while you press hard down on the disc until the vacumn kicks in, open the seacock and then screw on the lid.
Worked for us.
Not sure about the muck coming out.
Cheers