Kawasaki Ultra LX (NON SC) Water getting into engine

[blakegjones]

Considerable difference between my 2010 and 2013 LXs. The 2010 has two water boxes, the 2013 only one. They removed the flotation on one side of the '13, too!

Yes Steve. I’m talking only about the pipe from the water box to the back of the ski.

[vmattprice]

All,

Did anyone ever figure out the fix for this?

I've seen suggestions about routing the lines high above the water line, potential internal corrosion of the water box/exhaust, check/clean reed valves, etc..

Can you not install one-way inserts in-line in the tubing to only allow water to flow one way? Or is the point the water is 'supposed' to be sucked in when in motion, but the issue is while stopped, it continues to come in when it shouldn't? Not super familiar with the issue, but have a 2007 Ultra LX in the shop now waiting on an engine rebuild, so would like to know the ideal suggestion to relay to my mechanic, who might already know about this.

Perhaps a valve inline that keeps water out unless a certain amount of pressure is applied (which could be enough while the ski is running?)

What about looping the lines a couple of times? Assuming while running, there is enough suction to create the needed siphon whereas while stopped, that "should" prevent water from being forced back into the engine?

Thanks,

Matt

[blakegjones]

All,

Did anyone ever figure out the fix for this?

I've seen suggestions about routing the lines high above the water line, potential internal corrosion of the water box/exhaust, check/clean reed valves, etc..

Can you not install one-way inserts in-line in the tubing to only allow water to flow one way? Or is the point the water is 'supposed' to be sucked in when in motion, but the issue is while stopped, it continues to come in when it shouldn't? Not super familiar with the issue, but have a 2007 Ultra LX in the shop now waiting on an engine rebuild, so would like to know the ideal suggestion to relay to my mechanic, who might already know about this.

Perhaps a valve inline that keeps water out unless a certain amount of pressure is applied (which could be enough while the ski is running?)

What about looping the lines a couple of times? Assuming while running, there is enough suction to create the needed siphon whereas while stopped, that "should" prevent water from being forced back into the engine?

Thanks,

Matt

Hey Matt. I just looped the outlet line from the port side water box to the back/outlet of the ski as high as it will go.

This issue only seems to present itself when the ski is loaded, perhaps two people or one with cargo, and it is deep enough in the water for the water to flow back through the cooling hose outlet.

I have looped my high but haven’t had a chance to properly test it since my engine rebuild. I will try and test this week and let you know.

I did try a one way/ non return valve on the outlet but it did not work because the one I used was not spring loaded. And it wasn’t sealing properly. If the air suction valves on top of the engine ( at the head cover) are maintained clean and operational, there should be no reason for the engine to suck up water if a siphon is created if the water outlet line to the back has been routed high enough.

[dfc1971]

I had exactly this issue with my LX - when heavily laden after running it would suck water into the pistons on startup. We also had what with hindsight was a related issue - occasional moisture/condensation on the plugs after running making it hard to start and occasionally took on enough moisture that it was on the verge of hydrolocking. It seemed to be worse if I dragged the ski backwards (the tide had come in so dragged her back into shallow water using the ski rope)

It turned out to be as others have described earlier - corrosion in the exhaust manifolds, both the first and second sections, meaning that cooling water from the water jackets got into the exhaust and sucked into the pistons on startup. The first waterbox wasn't much better either. (The previous owner neglected the poor old girl - I've been fanatical with my flushing and cleaning!!)

I think the heavily laden thing might have caused there to be more pressure in the system when sitting low, because our issue got worse over the course of a couple of years to the point where the ski would hydrolock after every run, even when not laden at all.

I pondered all sorts of elaborate solutions to keep pressure out of the system, but at the end of the day it should not be happening and any workarounds are treating the symptom of the problem, not the cause.

I replaced the 2 exhaust manifold sections and the first waterbox, and now she runs like a dream.

To confirm that there was an issue before committing $$$ to new parts, I pulled the exhaust off and separated the first and second sections, sprayed WD-40 into the exhaust tubes, then watched it come out of the cooling water channels proving that the wall between the two had corroded through.

[steve45]

Thanks, dfc1971!Can you post of picture of the corrosion? You replaced the manifold, exhaust pipe, and muffler? That was expensive!

[dfc1971]

Hi steve45. I didn't take any pictures, but if you search the Kawasaki How To forum for "Kawasaki Ultra LX- Water in cylinders" someone else has taken pictures of theirs, in fact it was their post that made me take a closer look at mine. Mine was exactly like theirs - the lower two tubes were full of craters!
I did indeed replace the two exhaust manifold sections and first waterbox, but thankfully partzilla.com is a fraction of the cost of the Kawasaki dealers (at least in New Zealand) although it was still fairly pricey. With the amount I've spent on the ski over the 5 years we've had it, it'd have been cheaper to buy one new!!!