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How to add a Shutoff Valve to your boat's cooling system

adrianp89

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What do you guys use to cut the hose?
 

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PJ73

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Bump
 

Daron

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Ok, so I've given this topic lots of consideration. I like to prepare for the worst, within reason; everybody has their comfort zone. I have a masters degree in chemical engineering, and I know that installing a valve will always create a resistance to flow relative to a no-valve scenario. In this case, I'd have to dig into my old textbooks to figure out what the reduction in flow would be with the valve wide open after I install some pressure valves before and after the ball valve. I'm not going to do this because I spoke with Yamaha and asked them if they knew what kind of tolerance there was with respect to reducing flow by adding a valve, and their answer was simple, "we don't know, we've never tested this, so don't do it". Obviously many have successfully done this on many models, but if you have a warranty, and your engine fails, this is an easy one for Yamaha to use to void your warranty.
That's my perspective.
I'm going with the radiator hose clamps.
Maybe not the easiest to clamp on in rough seas while laying between two hot engines, but that's what I'm comfortable with. And in the end, maybe I'll have some scars to use as a story to tell over a beer or two, or three, or four...
Just my 2 cents.
I just read through this whole thread some areas twice, as I am wanting to do something about being prepared for an engine(s) failure on the water, and not having to go at wake speeds for hours to limp it home. It wouldn't surprise me if every dealer gave you a different answer. I just got off the phone with the dealership I purchased mine from and talked to the service department, they said they encourage them, that the tow valves are a great thing and they recommend them. They said there would be no warranty issues for something like that because it is protecting the boat from severe damage. I think I am leaning towards the Island Racing valves.

My next question may seem dumb, but I am piecing my knowledge of the system together through this forum, so be gentle please. When I pull my boat out of salt water and hook up the hose for flushing my Salt Terminator through the system, do I close the valves? If you leave them open I see it's just normal. But if I close the valves does it force more cleaning solution through the cooling system?

BTW, I found this for dispensing my Salt Terminator through, and so far it works good. They're hard to find, but I think it may be because they might be discontinued. It's much smaller than the picture may make it look. I'll send a pic of mine later when I'm out at the boat. I fill it half way with solution (which is maybe a few ounces) and it takes about 3 minutes to dissolve it all while it's flushing, that's per engine.

Pressure Washer G-Injector -- Green Earth Technologies

91745
 
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Daron

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Here it is in “life size”. You can see it barely fits in my hand, I think the total capacity is maybe 7oz. I have it all set up for quick connect hose fittings to my house hose.
91764
 

Daron

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Also, I’m confused on the valve placement. The original poster of this thread placed his AFTER the “Y” fitting. The diagram that was uploaded says to place them on the line UNDER the red line/hose. So in my picture, I place them inline of the BLACK line UNDER the red one, correct? (forward or aft of the stern being my choice). The red line/hose goes to the flush hook up line, correct?
91769
91770
 

JetBoatPenguin

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That is my understanding with what everyone said if you place the shut-off valves in the engine compartment.
 

tdonoughue

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Yes. I, myself, considered placing mine there (in the engine compartment) for about 13 seconds until I actually tried to reach back there and do anything. Then I went for the cleanout tray.
 

Daron

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Yeah, I'm going for the clean out tray area as well, just confirming to install them on the line before the "Y" (under the red line) where the ribbed hose wrap/sleeve is, and follow it through the stern wall aft and then install them there. I was browsing around Lowes yesterday, I didn't buy these but I liked them a lot. They are all very hard and thick PVC and no metal (so no corrosion issues) and plenty of straight or reduction adapters available to choose from. I need to get into the clean out compartment though and measure the inside diameter of my hoses first. Anyone see any reason why these wouldn't work? They really are very strong/hard valves, 3/4" and 1/2" valves available.

91945
91946
 

tdonoughue

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Just that the hose is an odd size. No reason why these shouldn't work, I would think. But I found on doing mine (I bought 2 size valves), one size was too big and one size was too small. I used the too big one, but it was a @#$$@ to get on... I used brass ones, so maybe you will find a better size selection with your reducers?
 

Jgorm

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The brass valves linked earlier work great. I think it was 14 bucks for 2 shipped.
 

VaMarine

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Also, I’m confused on the valve placement. The original poster of this thread placed his AFTER the “Y” fitting. The diagram that was uploaded says to place them on the line UNDER the red line/hose. So in my picture, I place them inline of the BLACK line UNDER the red one, correct? (forward or aft of the stern being my choice). The red line/hose goes to the flush hook up line, correct?

View attachment 91770

Did anyone get back to you as to if yours works, or were you able to confirm your set up works? Im assuming if you went on the front side of the Y then your blocking both (Flush and intake) sets of water coming into the engine and thus not getting anything into the engine.
 

Scottintexas

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Did anyone get back to you as to if yours works, or were you able to confirm your set up works? Im assuming if you went on the front side of the Y then your blocking both (Flush and intake) sets of water coming into the engine and thus not getting anything into the engine.
This is correct,
the original intent of these valves were for blocking normal cooling water flow if the boat needed to be towed, there for before or after the "Y" didn't matter and the fact that you have more room forward/up stream of the Y made sense.

over the years we've come to understand especially if you salt water flush, installing the valve on the line from the jet intake will force 100% of the flush into the engine vs. back feeding some out the intake screen at the nozzle, unfortunately there's usually little room between the Y and the wall and some (like Geoff Coopers post in the FAQ) chose to put the valve under the cleanout hatch,


.
 

Robert hare

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Another option on the valve placement.

I put my valve between the jet intake and the wye fitting (where the flush line is connected), not between the wye and the engine as shown above. This way when I flush my engines, I close the valve which forces all the flush water through the engine and none leaks out the jet intake. I found for me the best place to put the valve was under the clean out tray, I did not want to reach to the rear of the engine compartment hanging all over a potentially hot engine to operate the valve. On the 2007-2009 models (not sure on other years) the cleanout tray has an access port next to the each cleanout plug. The cooling line for each motor runs directly below the access port. With the valve installed and the access cover removed, I can reach the valve.
Can you take pictures and add to your post please.
 

Julian

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Since our boats have an open vs. closed loop cooling system, there is a potential of flooding the engine through the exhaust if there is not a positive exhaust pressure pushing out and preventing water from entering there. While underway, and the engines are at high revs, there is no danger of that, but when an engine fails or you are being towed, the risk increases dramatically. Therefore, the owner's manual tells us to operate at no-wake mode to return to port. That way the water is not moving at a rapid rate and is less likely to jet up into the exhaust. However, operating at no-wake speed is painful if you are several miles from port and need to get back because of an inoperable engine. There are many that have shared their painful stories of operating for over 5 hours to get back to port. Since I am inpatient and would be poking my eyes out if I had to travel that far in no-wake mode, I decided to install a valve that would simply cut off the potential for water to enter the engines through the exhaust. Some others carry an automotive clamp or vice clamp with them to achieve the same thing. I worry about the damage the clamps may cause to the hose, so I opted for the valve and I like the clean look and convenience of just turning a valve.


This is actually a very simple and inexpensive mod. The hardest part is working in such a small area, especially if you have big hands like I do. Because of the little space I had to work in, it took me about and hour of work time to complete this project.

Supplies:

2 brass shutoff ball valves (1/2 inch or 5/8 would probably fit tighter)
4 barb fittings (same size as ball valve)
4 hose clamps
1 roll of plumbers tape
1 hose cutter (anything that can make the cut in the hose)
1 6" - 1' piece of 1/2 hose - It may have been 5/8 in so check hose size. (You may not need. This is incase you do not have enough hose exposed after cut to allow the barb fitting to fit all the way before hitting the fitting on the other end of the hose.



1. Locate the hose at the rear wall of the engine compartment at the bottom left of each engine.


2. Cut the hose before the "Y". It is about 4 inches long. If you cut exactly in the middle, you might be able to use the cut hose and not replace it with longer pieces when you are installing the barb fittings.



3. Wrap the threaded end of the barb fittings with plumbers tape.

4. Screw the threaded end of the barb fittings into each end of the valve and ensure a tight fit.

5. Make sure the clamps are in place but loose over the existing cut hose.

6. Insert the barb end of the fittings between the cut ends of the hose. You will know if you need to replace the cut hose if the barb end hits the fitting from the other side and does not fit in all the way. If that is the case, cut a piece of hose long enough to fit the barb fitting without hitting the fitting on the other side.

7. Slide the clamps into place and secure.

Images appear to be broken @OperationROL
 

Chatt_Jetsetter

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Edit: found my answer, the Vortex's have a shut off valve and max tow speed is 15mph.

Original:
Reading through this thread, I'm understanding that if you tow your boat you need to close off the water inlet with a valve or clamp to prevent engine damage. Does this only apply to boats with an open loop cooling system? The majority of owners here have Yamaha's; I have the Chaparral Vortex with Rotax and its a closed loop, would this apply to my boat? Thanks!
 
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tdonoughue

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I don't know directly, but check your manual to see if you are supposed to only be towed at no-wake speed. That is what the Yamahas have (because above no-wake speed, you can suck the water into the engine--which is what the valves prevent).
 

Monster77

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I used 3/4 ball valve with 5/8 barbs from Home Depot. To make your life so much easier heat up hose before pushing on. Disregard the zip ties, I was attempting to prevent the hose from moving back and forth while I was working the valve back and forth to get it loosened up. First few times opening and closing was stiff. Works great and solved my lack of water pressure from garden hose.
 

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