Raw water in the beilge whaen underway

[Hornet_UK]

Hi, I THINK I have found the problem but won't know for sure until we do the repair over winter when out of the water. I am pretty sure water is coming in via the trim tab hyd cylinder top mounts, I imagine that they have some sort of gasket which is opening up very slightly .
I drew this conclusion because we get the most water in when the trim tabs are down (hyd cylinder pushing against the hull) and we are at displacement speed with the boat dragging in the water. We get almost no water when at planning speed when the cylinder top is bearly in water .
As you have sent in the thread there was mention of transom and clamp ring being the problem however when I put this to guys that really know boats all said its highly unlikely so I wouldn't get to sidetracked by this, not impossible but very unlikely was the concensus.
If you sort yours soon I would be interested to hear, because I have learnt to work around it in the short term I won't be remedying until winter lift.
Regards Nigel

Thanks for the update Nigbb, it sounds like I have a very similar problem for sure. Before I bought the boat there was a problem with one of the Trim Tabs leaking oil and this was repaired apparently. I suspect that fixing the leaky trim tab may caused the leaking into the boat issue plus my starboard trim indicator has packed up also.

 

[Nigbb]

Thanks for the update Nigbb, it sounds like I have a very similar problem for sure. Before I bought the boat there was a problem with one of the Trim Tabs leaking oil and this was repaired apparently. I suspect that fixing the leaky trim tab may caused the leaking into the boat issue plus my starboard trim indicator has packed up also.

That's weird, my indicator panel does not work in the starboard side either, both tab work fine but no indication. I forgot to say in my previous post and maybe you already know this but there is a void on both sides between the transom and the engine bay which has a hole in it and that void fill with water and then trickle into the engine bay.
As I said I won't fix mine until winter lift but if you do yours sooner I would be interested to know the result.
Cheers Nigel

 

[Hornet_UK]

That's weird, my indicator panel does not work in the starboard side either, both tab work fine but no indication. I forgot to say in my previous post and maybe you already know this but there is a void on both sides between the transom and the engine bay which has a hole in it and that void fill with water and then trickle into the engine bay.
As I said I won't fix mine until winter lift but if you do yours sooner I would be interested to know the result.
Cheers Nigel

No I didn't know about the void but I'll take a look at the weekend! My Trim Tabs are the same both work fine just the Steamboat indicator not indicating, I'll not lift again until next year but will post when it done.

 

[Nigbb]

I've just found this thread and have asimilar problem with my C35, was there any conclusion on the cause and solution to the problem?

UDATE Hi, just thought I would let you know we have another theory, with the recent heavy rain storms that we had we now fine fresh water in the engine bilge so with more investigation it seems that the bathing platform may be the problem. For sure when sprayed with a hose we have are getting some flow into the hull and iam assuming that when we are running at slow speed water is buildup around the underside of the bathing platform and getting in that way. When out of the water I will remove and re seal the rubbing strake, hopefully this will cure the problem.

 

[jrudge]

The classic way is talc that then shows water lines. Clearly no good if it is swimming in water but will help if you catch it early enough

 

[ptr247]

I had the exact same problem last summer on a Sessa C35. When underway water gets into the bilge. Had a friend of mine down near engines while i planed boat and we saw water coming in from 2 locations in the platform: (1) the fender and (2) the drain plugs found under the ladder hatch and small storage space on port side. Drain plugs were removed, cleaned and sealed properly. Situation improved but water ingress from fender remained. Boat lifted today and yard will remove fender, change screws and re-seal. Hopefully that will resolve problem.

 

[Nigbb]

Agh, that's interesting I need to look at the ladder hatch, I have had to boat out of the water over winter and removed the fender rail, re applied sealant and re fixed, its better but still when it rains I am getting water in engine room. This problem is driving me crazy, I will defo look at those plug on in the ladder locker.
Cheers Nigel

 

[simonfraser]

Rinse it alL out with fresh, leave it open to dry, else you’ll have corrosion to deal with as well

 

[DaveMC]

Did you ever resolve this?

 

[Nigbb]

I have since part exchange it so don't own it anymore, but we deduced that it was getting past the sealant on the rub rail further forward and then running down and giving the impression it was getting in further back around the bathing platform. My next move was to take rub rail off further forward and re seal. It was a "one day job but I never got around to it and ut didn't bother me that much.

 

[Refueler]

I know its old thread .. OP has sold boat on ... but :

I bought a Primor 24 with outdrive leg. While sitting on mooring - as with OP - literally nothing in bilge. But when using the boat - I woul get a couple of bucket-fulls of water in bilges.

Indications were that outdrive leg bellows were leaking - as there was nothing coming from engine cooling.

Finally I was fed up with it ... and we lifted the boat ... I had already agreed with yard - they would change both bellows and cooling water pipe on the leg - whether needed or not.

On lifting out - yard boss noted a hairline crack one side aft - and shorter but similar on other side same area ...

Basically the aft section of the boat is built of 3 open top boxes. Centre box is the engine 'box' then each side a box creating the wide hull form. Basically what had happened - was the joint along each side box to engine box had cracked .... while moored and quiet - the cracks were closed. But once the 170HP engine was in use - the weight and torque caused the cracks to slightly open.
This was obvious because when boat was out of water .. nothing came out - even though about 20ltrs of water was in side areas. When boat was flexed - water started to leak out.

Boat is 1970's build - just over 2 yrs ago - previous owner swapped out the 4cyl 130HP engine for the 6 cyl 170HP engine. This we believe sped up the fatigue cracking.

Solution was to grind out ... fair and fill with Fibre filled GRP ... then resin / matt over to add strength.

Boat is now bone dry ..... good for another 50yrs !