Shut off valve for cooling line when towing

oxnard111

Creative RE Purchasing
I was thinking about installing some sort of on/off valve on both my cooling lines coming from the pump... that way if I have the opportunity to go into shore before starting my tow home, I can shut them off so the engine doesn't get swamped from towing over 5-7mph... what do you all think? and if you were to think about doing it, what type of valve would you use?
 

Scorn800

Ride for life
Location
North NJ
I was planing on it with my surf boat but never did. I was going to run the line coming from the pump up to a thru hull fitting, then install a brass ball valve with barbed ends mounted in the front of tray then a another thru hull fitting back thru the bulkhead. I'm aonly running single cooling.
You'd have to have to do double of everything or increase the size of ball valve & fittings.
 

oxnard111

Creative RE Purchasing
I was planing on it with my surf boat but never did. I was going to run the line coming from the pump up to a thru hull fitting, then install a brass ball valve with barbed ends mounted in the front of tray then a another thru hull fitting back thru the bulkhead. I'm aonly running single cooling.
You'd have to have to do double of everything or increase the size of ball valve & fittings.

thats an interesting concept of doing it so that it accessible outside the engine compartment. but as you said I'd have to do double everything, which would require more dash space. I like though.
 

cookerq62

Life's Been Good
Location
Upper Bucks, PA
I thought about doing this as well. Mcmaster would have something, a brass ball valve would probably be your best bet. You really only have to worry about the pipe and the stinger so you could get away with one valve between the head and the bottom of the pipe, asuming your running a b pipe with dual cooling, and let the rest go overboard. This would also prevent someone from burning the motor up by accident.
 

oxnard111

Creative RE Purchasing
I thought about doing this as well. Mcmaster would have something, a brass ball valve would probably be your best bet. You really only have to worry about the pipe and the stinger so you could get away with one valve between the head and the bottom of the pipe, asuming your running a b pipe with dual cooling, and let the rest go overboard. This would also prevent someone from burning the motor up by accident.

I'm a little confused... I know water can get into the engine, but until now I never thought about how... so water fills up the chamber, then the headpipe, which leads to the engine all from the stinger only? What about the water that gets injected from the head pipe?

here is a very crude version of my cooling system... where would I need a shut off valve? I forgot to put it in the diagram, but I have dual cooling, going into separate barbs on the manifold.
 

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wydopen

Guest
...everytime im on the towrope the motor is already full to the brim so i guess it dosnt matter anyways
 

Crab

thanks darin...noswad!
Location
Seattle
Better yet, stuff some rags up in the pump inlet to keep the prop from windmilling, this will also keep water from feeding the pump lines. I have done this when broke down and need a tow, it dosn't take much to block the flow.:dunno:
 

cookerq62

Life's Been Good
Location
Upper Bucks, PA
You have 2 lines coming into the exhaust manifold and 2 coming out of the head.
Send one line overboard.
Send the second; valve-headpipe-stinger/overboard.

This way you will still have water going through the engine if you forget to open the valve.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
I'm a little confused... I know water can get into the engine, but until now I never thought about how... so water fills up the chamber, then the headpipe, which leads to the engine all from the stinger only? What about the water that gets injected from the head pipe?

here is a very crude version of my cooling system... where would I need a shut off valve? I forgot to put it in the diagram, but I have dual cooling, going into separate barbs on the manifold.

The water comes from the stinger, indeed.

The water injection holes need more pressure to really contribute.
A flow control valve between stinger and pisser sort of takes care of all that. :biggthumpup:
 

stuntbikemike

Time to ride
Location
clearwater
I was thinking about installing some sort of on/off valve on both my cooling lines coming from the pump... that way if I have the opportunity to go into shore before starting my tow home, I can shut them off so the engine doesn't get swamped from towing over 5-7mph... what do you all think? and if you were to think about doing it, what type of valve would you use?

i did that same thing last weekend...never going to tow if not needed:bigok:
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
Better yet, stuff some rags up in the pump inlet to keep the prop from windmilling, this will also keep water from feeding the pump lines. I have done this when broke down and need a tow, it dosn't take much to block the flow.:dunno:

The prop is not going to windmill, there is not enough waterpressure to spin the motor over, if there was you could jump start your ski if the battery was dead...... the water just flows around the blades.....


We have to tow skis all the time, never have we had one full of water (engine) unless it had already sank.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
If you fast enough it can fill the engine full of water,it all depends on the spped you are towing at,it dosent really matter if the prop spins or not.If you are forcing water through the pump it will pressurize the cooling system which will flood your engine with water.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
The prop is not going to windmill, there is not enough waterpressure to spin the motor over, if there was you could jump start your ski if the battery was dead...... the water just flows around the blades.....


We have to tow skis all the time, never have we had one full of water (engine) unless it had already sank.

The prop doesn't spin, you're right.
The water pressure through the pump is sufficient, however, to pressurize the cooling lines.

Don't believe me? (I got a scan page from the Yamaha owners manual if you'd like to see it! :biggthumpup:)

I've also sunk a few engines through fast towing before personally.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
It depends on setup a lot. Stingers, water routing, pissers, flow control valves and the like.
 
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