Fresh water flushing in salt water

luvinlife

So....my new to me 2006 FV 270 (volvo 5.7) has some type of hose attachment on the engine that can be used (I believe) to run fresh water through the engine. I am not sure but I think you simply attach a hose to it and it runs water in a reverse direction through the engine and out through the outdrive. I inquired about it during the marine survey. The surveyor said the process is not very effective and that using the boat frequently is the best thing for it in salt water. Does anyone else have this hose attachment or have an opinion on whether or not I should run fresh water into it after I run the boat? 

TonyWalker

I have the same set up on our 342.  I ran the hoses to inlets mounted on the transom below the rumble seat.  After most trips, I will attach the garden hose to the inlets (one at a time) and run each engine at idle for 5 minutes flushing with fresh water.  The current manifolds and risers are about 6 years old and are showing no signs of rust weeping out past the gaskets.  Sometimes the boat sits idle for maybe 6 weeks.  Sometimes more.

luvinlife

Sounds like just what I thought. Fresh water flushing whenever I can. 

reneechris14

I been told to be careful with when doing the flushing which is a great thing.Just run the boat when the water is on so water exits properly.

luvinlife

renee do i need to run the boat when flushing the water through it?

reneechris14

Yes 

randy56

I'm not a saltwater guy, but I have to ask, can you use standard m-u-f-f's on the outdrive on garden hose and achieve same result? Next Question, If you are a trailer boater such as Ras, or keep your boat on a lift, should you flush every time you go out? Ok one more, If luvin, leaves his boat in the water, does he use the hose connection inside, on the engine to flush, while in the water? If so what stops salt water from re entering through outdrive? well 4 Questions. 

reneechris14

Yes the garden hose and muffs would achieve the same result.Yes a good rinse will help keep salt away IE Ras's trailer. I believe luvinlife has flush connection mounted on tramsom or suction hose to pump.so when water is on with pressure the pump will take the fresh water and push though system.so when pump is off the fresh water stay in the heat exchanger and other things. Now with that if the water pressure is there and no exshaut to push it out it could fill the Y pipe up and come back in the riser in to cylinder.When your boat is in the water think of the height or the water line compared to the motor it's a boat half way up the riser.Think I got all 4?

reneechris14

Watch muffs with bravo3 because the pump up by the motor not like an alfa the pump is in the drive right way the muffs go on.

randy56

Gotya, let me see if I have this straight. 
1. So if Lovin is in the water, and he hooks up the hose to the water inlet. The water pressure from the hose, turns the pump to push fresh water through the system. Salt water pushes out through the exhaust. without starting engine? 
2. There would be no way to tell, if the Y pipe is filling up, and gravity/water pressure is removing salt water. 
3. What is the concern about the BIII and pump location, I know where each are located. Having both.  Always start my boat in the spring on muffs, to test,  then fall before changing oil. 
4. Sorry so many questions, someday I hope to semi-retire in the south, in the salt.

luvinlife

My outdrive is a Volvo DP. I thought I could simply run fresh water through the inlet on a garden hose to force fresh water out through the outdrive. Running the engine with water moving out of rather than into the outdrive does not seem right to me. 

randy56

I now under stand that you must have a fresh water flush kit installed. And it does not flow water thru the impeller. Found this info. 
http://www.quickflushvalve.com/how-it-works.html

Glassguy54

I just looked at the quick flush valve referenced above and think I want to order one of these. Any one know what the inlet hose diameter (ID) is for a Bravo III Mercruiser 350 MAG MPI, 2007 246 Captiva - 3/4" or 1-1/4"? Big difference in price between the 3/4 and the 1-1/4, like 90 bucks more.

reneechris14

It does flow though the impeller and though the FWC system then over board.over board out the risers this is where you want the exhaust to help push it out,like on the shamanic you posted.plus the impeller will help the pressure of fresh water.only need to run it for a couple of minutes.

reneechris14

@Glassguy54 1 1/4 inlet on the bravo 3

reneechris14

Salt water is corrosive but not deadly.many boats have no flush system (like mine)and stay in all year.@luvinlife do you FWC.

Glassguy54

Oh Poo.  1-1/4". That figures. $214 opposed to $123. Looks like pretty basic, easily sourced plumbing parts. Maybe I'll just build my own for like 30 bucks.

andyd

I flush with fresh water after every time I run the engine. Two or three minutes running the engine at IDLE ONLY, per manufacturer's instructions. VP 5.0L has the flush port closed by a blue plastic screw cap on the starboard front by the valve cover. Instead of having to unscrew the cap every time, I installed a plastic 3/4" ball valve and a 5' hose which stays attached & allows me to more easily connect to the fresh water hose. I do have a Salt Away hose dispenser, but it's a pain to hook up so typically I'm flushing with fresh water only.

Andy

luvinlife

Okay to recap so I understand this correctly.  My engine has a fresh water flush system installed on it. To use it after a day on the water I just unscrew the cap, attach a garden hose, turn on the water and run the engine at idle for a few minutes? Sounds easy enough. If it will extend the life of my risers and manifolds then I am in!  BTW I will have the risers and manifolds replaced before I splash in the spring as a precaution to give me piece of mind. 

Handymans342

Be careful of too much water pressure

reneechris14

Awesome 

Handymans342

Ok AL

rasbury

98% of my boating is fresh- if I do venture to salt, I dunk boat and trailer in the river to clean best I can. I also have fwc engine which was a must on my list. The salt water ramps u have been at always have hoses which I use- to bad the oceans aren't fresh water, who's idea was that anyway?

jcc2823

i was considering having this installed in my 290 FV 5.0 MPI 350 blocks as well.  Anyone know- are there any dangers- like the water pressure thing- how do you know how much water pressure from the dock hose is too much?  how do you regulate it and make sure enough water is getting through the engine?  sounds scary!  ;-)

andyd

Here's a photo of my flushing port mod I mentioned earlier that makes the process much easier.
Andy

Michael T

@andyd - awesome - another great boater mod!

luvinlife

Okay here is my real life update.  I am nearing my second season with the 270 in salt water for 5 months a year. I replaced the risers and manifolds. I put just 44 hours on last season and about the same this season. Because it’s a pain to open the engine hatch and remove the extra back seat insert my wife loves, I flush just occasionally. Thinking of having the flush port moved to the transom locker for easier flushing next season. 

Dream_Inn

great update and I would imagine having it in the transom locker, or even just mounted on the back would be much better. 

pistole

don't you guys have to close the thru-hull seawater ball valve before doing the fresh water flush ?