Tips on washdown pump install?

While we are on-the-hard, I am having the yard install a thru-hull to be used for a washdown pump. I will install the system later myself, but I am having the yard do the thru-hull. Any tips, pointers, or favorite pumps you all can recommend?

Thanks.

Here are a few thoughts:


Buy the highest flow pump you can, like this one Jabsco HotShot Series Washdown Pump. You will need all of this water flow to blast off mud from you anchor.


The pump should be mounted as close to the thru hull as possible to minimize suction losses. Use 3/4" hose if possible and put a strainer in the run.


If you have a spare 20 amp breaker on your panel, use that to power the pump. Otherwise wire it to a suitable breaker and put a switch on the panel. You don't want to leave it on all of the time. A leak in the discharge plumbing can sink your boat.


A nice twist lock deck fitting is this Jabsco one: Jabsco Flush Mount Deck Fitting. But if you can put a simple brass hose bib in the bow locker, that will do ok as well.


David

If its for anchor wash down, buy a pump with the most flow and pressure you can get. A 45# 3.5 gpm pump wont do well. I have a 75# 5.5 gpm. It does the job but would love something bigger.

why drill another hole in the bottom of your boat? T it in upstream of your raw water intake strainer with a shutoff valve.

Can you add a Tee to an existing thru-hull?

I hate adding holes to the bottom if it can be avoided.

Edit.... Post above at the same time, "great minds and all" LOL

Thanks David--- That flush-mount fitting is already in my cart at Defender I think I am going to mount that flush fitting on the side of the pilot house to avoid trying to snake the hose through some pretty unpleasant and inaccessible places in the bilge. That would also give me access to the back of it from under the galley sink.

And good tip about mounting it close to the thru-hull. I was beginning to think I was going to consider mounting it much further away. As-in... under the sink. That's over 10' away.

I was looking at this system: Johnson Aqua Jet WD 5.2 Washdown Pump Kit a 5.2x70 pump with a switch and fuse panel included. It also has what looks like a bulkhead or deck fitting, but it looks plastic, so That will likely hit the trash.

Thanks Frye--- I looked at higher capacity pumps that aren't specified as washdown, but they didn't have pressure switches built into them. There are probably in-line ones I could buy and I will look into that as an option. Still, I don't know if we need THAT much thrust The Neuse mud, while pretty gross, comes off fairly easily from chain.

SCOTTEDAVIS said:

Can you add a Tee to an existing thru-hull?

I hate adding holes to the bottom if it can be avoided.

Click to expand...

Well... I gave that some thought and discussion with the yard. What I decided is that I want a dedicated, single-system, for the pump. I didn't want to deprive another system of water during it's use, nor do I want a failure of THIS system to bring down another. And besides, another thru-hull doesn't dramatically increase the chance of failure. Another thru-hull is just another thru-hull. I have about 15 others and I don't worry any more about them than I would by adding another.

In addition, I am not a fan of adding more hose clamps to an already existing system. Adding a tee would add up to six more. That sounds like a much larger chance of failure than an unlikely thru-hull failure.

Tom.B said:

Well... I gave that some thought and discussion with the yard. What I decided is that I want a dedicated, single-system, for the pump. I didn't want to deprive another system of water during it's use, nor do I want a failure of THIS system to bring down another. And besides, another thru-hull doesn't dramatically increase the chance of failure. Another thru-hull is just another thru-hull. I have about 15 others and I don't worry any more about them than I would by adding another.

In addition, I am not a fan of adding more hose clamps to an already existing system. Adding a tee would add up to six more. That sounds like a much larger chance of failure than an unlikely thru-hull failure.

Click to expand...

Well thought out and all good points. I can't argue with your logic.

Go with a nice large pump, supply and discharge and you should be good to go.

I would recommend purchasing an angled fitting for the hose connection to the flush deck fitting. The straight hose fitting is difficult to connect and disconnect. These fittings are from New Found Metals (even though Jabsco's name is on them), check out the following link Product Catalog

That Johnson pump looks fine and you may be ok with that deck fitting. If it breaks then you can install the SS Jabsco fitting.


Using that switch panel with fuse you could wire it directly to the main breaker on the DC panel. These are often 50 amps so use #8 gauge from the breaker to the fuse and then #12 from the switch to the pump.


David

djmarchand said:

you may be ok with that deck fitting.

Click to expand...

You might be right about that, but that SS fitting looks pretty slick.

I've used Johnson washdown pumps w/o problems in the past.

Once concern I have with these pumps are the use of plastic in places where I would not want it to fail - the strainer, but more importantly the snap-lock connectors on the input and output sides of the pump. (Looks like Jabsco uses the same design.)

When mounting the pumps I make sure to mount them close to the inlet but above the waterline. Hasn't seemed to affect their performance, and if one of these plastic fittings fails it shouldn't flood the boat.

(No, I don't close the thru-hulls every time I leave the boat.)

danderer said:

I've used Johnson washdown pumps w/o problems in the past.

Once concern I have with these pumps are the use of plastic in places where I would not want it to fail - the strainer, but more importantly the snap-lock connectors on the input and output sides of the pump. (Looks like Jabsco uses the same design.)

When mounting the pumps I make sure to mount them close to the inlet but above the waterline. Hasn't seemed to affect their performance, and if one of these plastic fittings fails it shouldn't flood the boat.

(No, I don't close the thru-hulls every time I leave the boat.)

Click to expand...

Not so sure that just being above the waterline would stop flooding. If something fails and the cock is open to the sea, isn't there still enough pressure to push water out, or does it only have enough pressure to push it UP TO the waterline, but not above it? Damn, should have stayed awake in physics class!

Greetings,
Mr. TB. "...isn't there still enough pressure to push water out..." IF the seacock fails, yes water will enter the boat. IF a fitting/hose connected to the seacock fails and the open end of said fitting/hose is above the water line, no water will enter the boat. Never liked physics.

The notion that has been mentioned about getting the most powerful pump practical is a good one. Don't forget that the pressure will be reduced by the length of the plumbing run from the pump to the outlet.

Our boat came with a previous-owner installed salt water washdown system and while it is not what I think we would do if we were installing such a system ourselves it is very impressive. It's a big Jabsco impeller pump powered by a 1 hp Westinghouse AC motor. At the pump outlet the volume is about 23 gallons per minute. It's less than this at the bow and stern outlets, of course, but it's still sufficient to blast virtually anything off the chain and anchor. The downside is we have to run the generator to use it. But it has certainly demonstrated the benefit of having as much pressure and volume as possible.

I have got 6+ years of intense, year around use from one of these.

Shurflo Extreme Series Pro Blast Pump - 5901-3212 / 4258-163-E09

Very happy with it. Made in 12v as well. You really don't want to tee off an engine raw water intake.

"or favorite pumps you all can recommend?"

BIG!

If the boat has an inverter you might consider a home well pump 1 1/2 in or a pool filter pump, usually 2 inch.

These move a LOT of water and are almost all plastic these days so sea water is no concern.

If you install a good sized unit a Y valve so it can do duty as an emergency bilge pump would make sense.

A huge volume and pressure is required to get stinky mud off chain , the usual "deck wash" service.

No inverter... yet. We had good results with the basic off-the-shelf Jabsco pump on our first boat and I think the Johnson I linked to above will even be an upgrade to that. While I looked at some more powerful pumps, I really don't need a firehose to wash off mud

I do like the idea of adding a Y to it. THANKS!

Another question: The pump has a small strainer built onto it. Should we add a more conventional Groco raw water strainer too, or is that overkill? The Neuse can be kinda gunky and I wonder if the built-in one will clog too quickly.

Tom.B said:

Another question: The pump has a small strainer built onto it. Should we add a more conventional Groco raw water strainer too, or is that overkill? The Neuse can be kinda gunky and I wonder if the built-in one will clog too quickly.

Click to expand...

I'd put a strainer on it...Mine pulls through my head intake cock and has a small spin-off filter mounted above the waterline. Occasional cleaning is all it needs...

I second Steve's opinion. Our washdown pump doesn't have a strainer of any kind on it but the pump is so big it would probably pass gravel. But weed, mud, grit, etc. can be pretty hard on a flexible impeller pump so filtering that out would probably be a good idea in terms of impeller longevity.

And if it's something that's going to be used infrequently it can be a smart idea to turn it on for second or two every now and then to spin the impeller and park it in a different place.

I installed a lighted ON/OFF switch at the lower helm to draw my attention to the switch when it's on. It has reminded me several times when I forgot to turn it off after use.

You will use that wash down pump for maybe 5 minutes each time you anchor. Your engine's raw water strainer gets ten to one hundred times more use. I have put a couple of hundred boating hours on the Neuse, tributaries and Pamlico Sound and when I clean my engine's raw water strainer (a couple of times each year) I get a few blades of grass, that is all.


You will be happy with the pump's strainer.


David

George, thanks for posting the link to my website.

I'd try the pump with the strainer it came with. If you end up cleaning it often, it's easy to replace it with a bigger one.

Be sure to have the yard install a backing block and flanged valve. Don't just screw a valve onto a thru-hull and call it a seacock.

Marin said:

And if it's something that's going to be used infrequently it can be a smart idea to turn it on for second or two every now and then to spin the impeller and park it in a different place.

Click to expand...

Real smart, saltwater does not smell nice after parking in the pump/hose for even a few days.
Someone invariably grabs it to wash their hands and gets the rotten egg treatment!

HopCar said:

Be sure to have the yard install a backing block and flanged valve. Don't just screw a valve onto a thru-hull and call it a seacock.

Click to expand...

No backing plate, but a good flanged valve. It's only a 3/4" thru-hull and this boat has a thick, solid hull. Good amount of Sik-a-flex 291.

I've got a big pump ready to install. Plan to place it discretely, innocuously in it's own small plastic container on port corner of swim step... within just inches of water; will draw from deployed hose having screened end.. Will have available long flex hose at the ready for complete wash-down of boat at any time. Can be used to wash off mud on rear anchor. Front anchor is easily washed by large drop "plunking"... when necessary.

Only set up situation I've not yet fully figured is 12 V access... but I do have plans!

Hope to complete before next summer. Many projects lined up!

Happy Water-Pump Daze! - Art

"I really don't need a firehose to wash off mud "

Unless you get the chain clean of ALL the muck , the low tide stench will live in your anchor locker.

Lots of pressure , lots of volume is less scrubbing with a hand brush.

I agree with FF...lots of water and pressure. We have an older Jabsco 7gpm washdown pump (I don't think they offer it any more) and at times we need more pressure. We use a walmart 1200 pressure washer fed by the washdown pump.


Keep the pilothouse windows closed during retrieval and washdown.....

You will use that wash down pump for maybe 5 minutes each time you anchor.

Click to expand...

I wish! An all chain rode that's attached to a deeply buried anchor in sticky mud for a few days has taken us as much as 20 minutes or more to get all clean with excellent pressure and water flow. In Tom's cruising grounds, most of Cape Lookout Bight, South River, and Ocracoke all fall in that category.