Water cooling system

[Wisefam22]

Noticed on trip out yesterday one engine wasn't producing any water out the side of boat. Never received overheat warning, both engines ran great topped about 10500rpm (2006 sx230 mr1s). With the smooth water was running WOT 53ish mph.

Was going to try and blow that hose out. What is best way to go about performing that?

 

[Julian]

I start with a strong piece of eater eater string just to see if a mud dauber has nested in the hole. If it has, you can jamb it in the hole - and on your model boat, open the rear storage hatch and squeeze the tube while you do this. If you do this on the water, you can get some water to help flush it out.

I've also used the inside of a pen to good effect when I didn't have anything else.

 

[Gym]

Hi @Wisefam22. You most likely have a mud dobber nest or other debris in the line. The easiest way to approach this is with about 20 inches of weed wacker string. Push the string into the pisser port on the side of the boat. I find it better to do this while the boat is running either in the water or on the trailer while on the hose. This will help flush debris out of the line.

 

[Wisefam22]

The bilge is furthest to tail and the water holes I was speaking about are furthest towards bow. Tue 2 small holes near bilge are what? One was clogged.

 

[Julian]

Tue 2 small holes near bilge are what?

These indicate whether you have cooling water reaching the engine. Lack of water does not mean you don't have water reaching the engine....but could. More likely since the boat didn't go into limp mode...your pee line is simply clogged with a mug dauber nest. Some people stick golf tees in the holes once parked. They fall out when trailering, or get pushed out by the water.

 

[Wisefam22]

These indicate whether you have cooling water reaching the engine. Lack of water does not mean you don't have water reaching the engine....but could. More likely since the boat didn't go into limp mode...your pee line is simply clogged with a mug dauber nest. Some people stick golf tees in the holes once parked. They fall out when trailering, or get pushed out by the water.

Thanks. I'll be out over weekend and all day Monday. Might take the boat out tomorrow morning haven't decided. I'll prod the pee lines more once in water to see if I can break up what might be clogged in the one.

Should those 2 holes be peeing as well, or just the ones closest to bow?

 

[zipper]

@Wisefam22 Here is a link and a diagram to follow. https://www.yamahasportsplaza.com/oemparts/a/yam/50039f29f870021f60a116c7/exhaust-3 The two forward are exhaust cooling and the two aft are part of the thermostat circuit. They were relocated in 07 to the stern. To answer your last question...Yes, once the engines warm up and the thermostats open.

Edit: grass trimmer string worked for me when I had to clear mud dobbers from mine right after we bought it.

 

[Julian]

What Zipper said....some boats will only dribble at idle....but you should see two strong streams at higher RPMs

 

[Scottintexas]

@Wisefam22 you need to watch this video in our FAQ section about how the water flows, it's great information,

https://jetboaters.net/faq/how-does-the-cooling-water-flow-in-my-yamaha.101/


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