Flush out cooling system?

[Joe_the_boatman]

So in a bonehead move, I got stuck on a reef (of mud) out on the lake yesterday, going full throttle in about 2' of water.

After moving the ski, I noticed that the tell-tale water stream wasn't flowing nearly as much as usual. So, made it back to shore and ended our day out.

How can I flush that mud out? Putting the hose to the port at the top of the engine will only flush the stuff out the engine. I want to clean the whole system.

 

[Jeff Walkowiak]

Re: Flush out cooling system?

I would back flush the hose that goes from the jet pump to the engine, as for cleaning the engine water jackets themselves,, you would have to pull the head off the engine and get to them that way,, do not force water in as it can get in to the bottom of the engine where the crank shaft and bearings are and that will be a big mistake, since it didn't over heat on the way back the water jackets are probably not clogged.

 

[Joe_the_boatman]

Re: Flush out cooling system?

thanks. I'll try the normal flush w/ the hose and see how much water it flows.

 

[Jeff Walkowiak]

Re: Flush out cooling system?

if this is the kawasaki 750 you are talking about,, there is a right angle hose coming off the pump that feeds water to the engine,, this right angle has a tendency to get clogged with sand,, you can pull the ride plate off to get to the hose, remove it clean it and reinstall it.. on a 750 engine if you run it hot it will blow a head gasket,,

 

[Joe_the_boatman]

Re: Flush out cooling system?

Thanks for the info Jeff. It "free-rev'd" while stuck in the mud - about 5 seconds worth. Kill switch didn't stop it. Quickly moved it to water and it stopped. First time it's ever done that.

On the way back to the ramp, I noticed the tell-tale wasn't as strong as usual, and figured I'd better call it a day. On the trailer, I was blowing the water out the back and it free-rev'd again. I hit the kill switch, nothing. No water to move it to this time and I started to panic. Took the seat off and pulled the plug wires. Still kept running! Ran and grab my tools to start disconnecting the fuel system, then realized I should just turn the petcock to off (took me a second to realize that, I was in panic mode). Free-rev'd for maybe 30 seconds total. Steam was coming out the tell-tale. Pretty scary stuff. I know now from reading here to pull the throttle open, or close the choke to stop it.

So, in addition to flushing the cooling system, looks like I have a compression test to do, as well as find out why it ran so lean. I suspect the intake manifold gaskets may be at fault, and will replace them if they're not sealing right.

 

[Jeff Walkowiak]

Re: Flush out cooling system?

any vacuum leak will do that mine was base gaskets under the carbs,, also re torque the head on that engine every so often follow the sequence next to each acorn nut