Seacock Not Fully Closing

[BDofMSP]

My main raw water seacocks are not closing completely right now. When I clean my strainers they still allow a slow trickle of water to enter.

That's a problem because I was planning on pulling my aftercoolers for maintenance soon. I'm betting that's going to take awhile (days?), so I'm worried about the amount of water I'll be taking on during the project. Is there anything I can do to the seacock while in the water to reduce that leakage? I'm not aware of anything but thought I'd ask.

I have one of those orange emergency graduated plugs, but honestly I brought it over from my old boat and I'm not positive it fits my current hoses. Fortunately I've never had to use it, so I'm not even sure how well it works. And obviously I'd rather keep it out in the first place than just plug it, but that might be all I can do at this point.

Thanks,
BD

 

[Chrisjs]

Depending on the shape of the seawater inlet, you may be better off plugging it from the outside, so pressure will tend to push in rather than push the plug out.
Also, by doing this you should be able to work the frozen valve, get some lube in there and free it up to work properly.

 

[BDofMSP]

I like the idea, but I'm not really a fan of entering the water in the marina, what with Electric Shock Drowning and all. I wonder if I plugged it outside the marina whether the plug would stay in place when I drove back in.

 

[BDofMSP]

Never mind. Just reviewed pictures of the intakes and there are strainers over them anyway. Couldn't get a plug in there without removing those.

 

[menzies]

Close the through hull, disconnect the hose coming from the strainer and use a wooden plug in the strainer outlet.

 

[KnotYet]

Remove the hose from the strainer and insert a plug; a wooden dowel will do nicely.
Cinch up the hose clamps and no more leak for as long as you need it.
Work the seacock to your heart's content.

Dang, menzies!

 

[Pete Meisinger]

Before you pull the hose, try working the handle back and forth a number of times. Sort of "self lapping". Are you sure the handle isn't hitting something?

pete

 

[menzies]

Remove the hose from the strainer and insert a plug; a wooden dowel will do nicely.
Cinch up the hose clamps and no more leak for as long as you need it.
Work the seacock to your heart's content.

Dang, menzies!

 

[BDofMSP]

Thanks Pete. The handle is pretty stiff but it's not hitting anything. I will work it a bit though to see if it cleans up.

I'm not on the boat now but from pictures and memory, that's a pretty big wood plug I'll need. 3 inches maybe?

 

[menzies]

Thanks Pete. The handle is pretty stiff but it's not hitting anything. I will work it a bit though to see if it cleans up.

I'm not on the boat now but from pictures and memory, that's a pretty big wood plug I'll need. 3 inches maybe?

Actually you should have a complete set on board anyway. They sell them at WM or online. And they are plenty big enough.

 

[BDofMSP]

The set I find at WM only goes to 2". Not sure if that will cut it. I can look online for others. I have the emergency plug from WM, and it goes to 3", but it might be too long to fit into the outlet of the strainer before bottoming out.

 

[HopCar]

Remove the hose barb on the outlet side of the strainer and screw in a pipe plug.

 

[BDofMSP]

Remove the hose barb on the outlet side of the strainer and screw in a pipe plug.

Thanks Parks. Looking at the photo it wasn't clear to me that it was removable. If so, that would be the most direct (although possibly expensive) solution.

BD

 

[ScottC]

Have you closed the raw water discharge sea cock as well?
EDIT: (Sorry - kindly disregard the above comment. It's something unique to my Hybrid setup).


Addendum: I thought I had the same issue as you have when I was cleaning my diesel engine raw water strainer and some water still seemed to come in even though the sea cock was fully closed. Turns out it was simply water draining back from the engine, which is considerably higher in the boat than the strainer.

 

[KnotYet]

Thanks Parks. Looking at the photo it wasn't clear to me that it was removable. If so, that would be the most direct (although possibly expensive) solution.

BD

You can use a PVC pipe and/or plug for this short term situation.
No real need for anything fancy or expensive.

 

[BDofMSP]

You can use a PVC pipe and/or plug for this short term situation.
No real need for anything fancy or expensive.

Good point! I immediately went to bronze. There's no need for that. Thanks!
BD

 

[Rmlow]

Try draining the aftercooler and heat exchanger 1st. Seacocks may not be leaking.
looks like a Cummins 6C or B series engine from the pic.

Mine does the same and it stops after those are drained so you may be bleeding back thru the impeller a bit

 

[BDofMSP]

Have you closed the raw water discharge sea cock as well?

I'm not aware of any seacock on my exhaust, which is the raw water discharge.

 

[BDofMSP]

Try draining the aftercooler and heat exchanger 1st. Seacocks may not be leaking.
looks like a Cummins 6C or B series engine from the pic.

Mine does the same and it stops after those are drained so you may be bleeding back thru the impeller a bit

Interesting. Never thought that it could be coming from the other direction.

Yes it's a 6CTA 8.3 450.

 

[ScottC]

I'm not aware of any seacock on my exhaust, which is the raw water discharge.

Sorry - please see my subsequent edit & addendum in my post.

 

[BDofMSP]

Sorry - please see my subsequent edit & addendum in my post.

Thanks - yes I never considered that. I'll be looking into it.

BD

 

[vacser]

If the hose running from the strainer is long enough. Remove it from the raw water pump and tie it up above the water line.

 

[Elmo]

I had similar problem but seacock was going past stop. I learned to back it off just a tad and the drip stopped. You just had to find that sweet spot.

 

[menzies]

I had similar problem but seacock was going past stop. I learned to back it off just a tad and the drip stopped. You just had to find that sweet spot.

Have a closer look at your fitting. There should be a screw/bolt hole at the stop point for you to put a small screw or bolt in to stop the handle.

 

[Elmo]

Thanks. There was, and it did stop... But just after the full close point. Wasn't sure how to fix or adjust but it was a minor issue once I was aware. Before that I used to get around five gallons under the engine if I did a water pump replacement afloat.
Have moved to new boat and current owner of old boat was made aware of sea cock issue in writing.

 

[rgano]

If the hose running from the strainer is long enough. Remove it from the raw water pump and tie it up above the water line.

My thought too, or just put a new hose on it long enough to be tied above the waterline. Been there, done it.