Crank case water ingestion after ski sits

[DylanS]

Running a re-sleeved 1050 gp800 motor on a 5mm stroke for the past 2 years and have noticed that occasionally the motor would hydro lock for a brief few cranks than clear up and run again. This season after a complete tear down and rebuild with fresh gaskets I get it out in the water and it’s running funny as normal, bring it in the adjust low speed screws and find it water locked again. Pull the plugs and the rear cylinder is pulling up massive amounts of water from the case. This has been somewhat of an issue on multiple rebuilds and only now have I seen it be this bad. Any thoughts? Going to take it home for a leak down test, I’m leaning towards a gap between cylinder and sleeve or a cracked exhaust manifold. Anyone have any similar issues?? Love these issues right at the start of our season!

 

[Quinc]

Do a leak down test on the cylinder water lines first. Also are you running a water box? Water could be coming up through the exhaust.

 

[DylanS]

Do a leak down test on the cylinder water lines first. Also are you running a water box? Water could be coming up through the exhaust.

Just started running a box this season actually, issue didn’t go away, I had always assumed water was backwashing from pipe and spray fitting but never knew the case was filling
Will do test and post

 

[DylanS]

Fabricated Ex. manifold block off plates and did 70psi hose tests to make sure I had no leaks
Everything held
it’s this first gen WDK manifold
Can only get 3/4 bolts on the manifold by design and it’s spraying water into my exhaust ports
Guess I should have figured
Now I have to find the newest manifold or see if I could somehow cut bolt holes into this one without catching the coolant tunnels.

 

[DylanS]

Ended up leveling the surface of the manifold and cutting a new thicker gasket, problem solved!

 

[yamabro]

Glad you gave the update and resolve.

 

[Gratefuldeadshred]

Hey did you happen to take pictures? Was it leaking around every bolt? My wife’s ski is literally doing the same thing and we have always found it hard to believe water is splashing that far up the exhaust as we never leave it in the water. It’s always on the trailer and the trailer is always tilted down

Ended up leveling the surface of the manifold and cutting a new thicker gasket, problem solved!

 

[DylanS]

Hey did you happen to take pictures? Was it leaking around every bolt? My wife’s ski is literally doing the same thing and we have always found it hard to believe water is splashing that far up the exhaust as we never leave it in the water. It’s always on the trailer and the trailer is always tilted down

What exhaust pipe and tilted down as in nose or tray down?
Does she ride and put it on the trailer and then it’s hydro locked?
I have pics of the manifold somewhere, imagine a laydown pipe manifold but it’s missing the bottom two inner bolts. It would end up spraying loads of water into the manifold and kill the bottom end.
Occasionally I will forget to run the current ski on the stand before putting it on the beach cart and pulling it up the hill and typically I end up with cases full of water (no suprise) with a rrp laydown and waterbox.
Also had this issue on my 1200 recently with a blown dome o-ring.

 

[Gratefuldeadshred]

wdk lay down pipe on wdk 927. Trey down as if the ski was loaded. Where we ride we can have the trailer chillin in the water so we just use that as our stands. We have already gone three one motor I’m convinced is from water ingestion

 

[Sparkplug]

wdk lay down pipe on wdk 927. Trey down as if the ski was loaded. Where we ride we can have the trailer chillin in the water so we just use that as our stands. We have already gone three one motor I’m convinced is from water ingestion

Splashes from wake can push water into the exhaust. I dealt with this. I used to leave my ski on trailer when riding at my spot. It only ever affected my lay down pipe ski.


I made a pvc stand. And now pull the ski put of the water enough that a passing wake could not push water up. I heavily debated going to a b pipe on my dasa after this last service interval. Because of the ease of water ingress with a laydown pipe.

 

[DylanS]

^ this coupled with WDK’s flat exhaust manifolds is a recipe for disaster.
I had better luck with a power factor box for what it’s worth but typically I put my ski on the stand backwards so that the tray is towards the shore.

 

[Gratefuldeadshred]

Yea the ski doesn’t sit in the water at all while not riding it.

 

[DylanS]

Yea the ski doesn’t sit in the water at all while not riding it.

I see I see
if she’s running the early cast manifold I’d say it’s worth a shot having it machined flat again or using a glass pane and some sand paper to smooth her out. If it’s the new billet style I doubt that’s your issue but it’s worth a pressure check.
How are the water lines run? Any chance your line connected to you water injection fitting at the manifold is draining down ?