Clearing the sea water intake

conniemarie

Member
Joined
May 27, 2012
Messages
19
Fluid Motion Model
C-302 SC
Vessel Name
Connie Marie
On our way home from Desolation Sound we found that our R27 had managed to get a bunch of green algae and seaweed stuck in the seawater intake. Following one of the tips on this forum, after cleaning the green stuff out of the raw water strainer we opened the seacock to make sure the flow was good. The flow was not good, barely a trickle! We think we picked up the crud in the harbor when we got gas before docking for the night when we did our all of our checks for the next mornings travels.

After a very sleepless night trying to figure out a solution, we decided to try to blow it out backwards. Last year we had PB in Port Alberni install a freshwater switch/join on our raw water wash down system. This helped to save the day. We switched the system to freshwater so it pulled from our freshwater tank, stuck the jet nozzle in the raw water strainer intake and put out a jet of freshwater backwards into the inlet. Happily it cleared away the plug and we suddenly had very good water intake again.

Has anyone else had an experience like this. How else can you handle this situation when you're traveling on your boat?

I know that Andrew cleared an intake for someone on the DS trip by diving under their boat, but I have no idea whether the intake is actually accessible enough for someone inexperienced to clear. I don't even remember seeing it on the bottom of the boat when it was on the trailer. The manual also does not point out where it is or whether it requires tools to access.
 
The intake is a small brass grate on the bottom of the boat. It is hard to see when on the trailer because it lies inside the trailer bunks.

Have had the same problem on my 29 and just about every boat I have ever owned. Sooner or later something will plug the intake. I have been successful blowing the stuff out with the wash down pump even though it uses the same sea water strainer. the pump takes the water in the strainer then returns it to the same strainer so you get a couple of seconds to blast it out if you stick the end of the spray hose into the intake pipe. Warping some electrical tape around the end of the nozzle to make it the right size so it will create a tight seal to the pipe helps.

Because this happens, occasionally, to every boat, and some have no wash down pump, I carry a CO2 drain blaster in my tool kit. They are available at a good professional plumbing supply house, used to blow out air conditioner condensate lines. Cost about $20 with a couple of CO2 cartridges, and replacement cartridges are available separately. They clear the line FAST with a blast of gas that pushes the water back out the line clearing the obstruction.
 
That drain blaster sounds like an essential piece of safety equipment! I will try to track one down to put onboard.
 
Interesting to read this thread as Walldog (Herb) in an earlier post thought this to be a rare occurrence, and I had suggested a solution with a T section and stop cock setup to perform the back flushing to clear the intake grate.

This is the 5th post related to this problem I've read.

I do like the CO2 Drain Blaster solution… thanks for sharing that. 🙂
 
Hi

My biggest problem with the Ranger Tugs has been raw water intake getting clogged with seaweed and junk.
I average 4 time each year in removing my boat from the water to cleaning it. I am looking for a good solution for this problem and my have found it with Tugnuts.

Dennis

Tug of my Heart 11
R27
 
Hi All,
I installed a "T" for flushing the salt water from my raw water system after a cruise. With the engine off and leaving the water inlet valve open the fresh water goes back through the sea strainer and out the intake. I then start the engine and close the sea valve (now only freshwater is flowing through the raw water system) to flush the salt out of the engine.
With the engine still running I turn on the wash down pump and keep it running while I go forward to turn off the engine. I then turn off the water supply and the wash down pump.

CAUTION...as someone in a previous post correctly mentioned if water pressure is left on with the engine not running there is a possibility of water entering an open exhaust valve and causing a hydraulic lock on the diesel. 😳

In the future I was thinking of installing a shut off valve and a check valve and plumbing in the on-board fresh water pump instead of using the dock water. This would give me better control of turning the water off and on.
 
I usually just let my water hose run into the sea strainer with the cap removed and sea cock closed. any excess water just drops to the bilge and runs out the bottom.
 
I saw a couple of posts interested in the CO2 drain cleaner so I thought I would post additional information.

The one I have, which works great, is the Gallo Drain Gun by DiversITech.The spelling is correct (d i v e r s i t e c h). Did I mention it works great!

Careful, while I was looking this product up to get the information I saw them priced from $29.95 to $119.00 for the exact same item. Mine was under $30 at my local supply house.

I had to build up the cone size using electrical tape but it works fine although I think other adapters are available.
 
On a previous boat the overheating alarm went off. I immediately shut down the engine and whle sitting in the cockpit wondering what to do next, saw a piece of plastic floating away from the transom. Started the engine and temp returned to normal. I wish all repairs were that easy!

Adagio
2009 R 25
 
Plastic bags are the worst .
 
We see the vessel assist boat in front of us. We are getting 1000 miles to the gallon!

This posting was perfect timing. Tried a few tricks but didn't work.

Bob and Nita
 
My wife likes to wash her hair in the galley sink. Long black hairs are not friendly to plumbing. It finally got clogged up. I rigged up my dingy pump with some duck tape to the drain tube and pumped until it blew it out. It may be possible to use the dingy pump in the same manner with the raw water inlet?
 
I bought some rubber stoppers and brought a drill along on my trip this year. I plan on trying to use the pump by drilling a hole an appropriate size in an appropriate sized stopper at such an inappropriate time. Lets hope I don't get that opportunity now that I am so prepared ;-).
 
Thank you, Todd, for the great idea of the Gallo Drain Gun. My R29 was the one from whom Andrew so gallantly and heroically removed the offending plug of sea grass by diving into the frigid waters off Salt Spring Island on our DS cruise.
No more sacrifices! I am off to the next plumbing supply store.
Ted Steudel :idea:
 
We were on the Desolation Sound cruise and heard the blow-by-blow description of Andrew's "rescue dive", so after seeing the posts about the drain gun, I ordered one! It arrived yesterday and the fitting indeed does seem too small. I did notice that there were adapters available on Amazon, so will be checking them out. Anyone else order the adapters?
 
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