Water coming into engine compartment under power. See pics.

[GregGreg]

If you removed the rubber hose in between the yellow arrows you would see the impeller shaft . The area with the red oval has a seal if you have the impeller shaft out you can see it ,its the first area the splines will pass through as you're inserting the shaft. These get damaged if you sucked up a rope and it spools onto the shaft then gets bound up and rubs on that seal . Take a look at that area if you have the jet drive unbolted. In severe cases that fiberglass are has even cracked

View attachment 224508

So I removed the entire external jet system including the shaft and impeller. I did not see any cracks or anything unusual. Actually impressed that I didn't. The water is coming from behind those two yellow arrows. The fiberglass is molded in what looks to allow water to drain to the back of the vessel. It is like that under both of those large washer and bolts; either side of the impeller shaft. That's where my leak is. Only leaks under power. Doesn't leak externally with water filled into the bay/hatches. Doesn't leak with the vessel sitting in the water with or without the engine running. Only leaks when throttle is applied to the engine.

In the screenshot here. It shows the space between two pieces of fiberglass; located on the stern side of the engine bay wall and is the same on either side of the impeller shaft hose. Water comes from this area. I do not know how to access this area and it may be coming from the cylinder shaped piece of fiberglass on the bottom middle of this screen shot.

 

[anmut]

So I removed the entire external jet system including the shaft and impeller. I did not see any cracks or anything unusual. Actually impressed that I didn't. The water is coming from behind those two yellow arrows. The fiberglass is molded in what looks to allow water to drain to the back of the vessel. It is like that under both of those large washer and bolts; either side of the impeller shaft. That's where my leak is. Only leaks under power. Doesn't leak externally with water filled into the bay/hatches. Doesn't leak with the vessel sitting in the water with or without the engine running. Only leaks when throttle is applied to the engine.

In the screenshot here. It shows the space between two pieces of fiberglass; located on the stern side of the engine bay wall and is the same on either side of the impeller shaft hose. Water comes from this area. I do not know how to access this area and it may be coming from the cylinder shaped piece of fiberglass on the bottom middle of this screen shot.

Can you reach that to just gob some silicone on the spot that you think is leaking and try to seal it up?

 

[GregGreg]

Can you reach that to just gob some silicone on the spot that you think is leaking and try to seal it up?

Yes, but I couldn't feel anything that felt different than smooth. What's really odd is the water will ooze in under throttle but once throttle is gone it QUICKLY disappears like it never happened.

 

[GregGreg]

I purchased a bore snake camera and placed it where the water intrusion is happening. I could not find any obvious signs of entry but I did not spend much time looking. Heat index was 110 that day and it looked like I was the water intruding.

 

[Cambo]

Have you measured how much water comes out when you pull the drain plug? Maybe grab an empty gallon jug pull the boat out while on the ramp with the boat on an angle stern lowest take the drain plug out and let it fill the gallon jug. How many gallons or not even a gallon ?

 

[itsdgm]

Just saw your post. Sorry to see you having these kind of issues.

1. I’m curious, you said initially that you have a used FSH 190…… did you just recently purchase it and it has had this issue since you’ve owned it? Or have you owned this for a while, and it just started leaking?

2. I see that you tested the bildge for leaks and put some water in it. To be honest, I’ve never had to do this on my boat (a waverunner yes). But the guys that I’ve seen do this have put a lot more water in the bildge than you did to test this out, I mean a lot of water.

3. You stated that the water felt warm. This usually indicates an exhaust system leak. I’m sure you’re aware that water is used to cool the exhaust system, muffle the noise (in the water box” and then gets pushed out the “tailpipe”. This water starts at the pump housing and is directed back into the engine compartment and splits into a few places to cool the engine and exhaust. In your video the water volume appears to increase in volume as the motor accelerates. This would happen if it’s a cooling line issue.

Edit: one thing that you could do to determine a cooling water/exhaust line issue would be to clamp the incoming water line (for a few seconds to see if the leak stops. Obviously you’d only want to test this for a few seconds to see if it stops the flow.

4. Another potential cause would be the intermediate bearing housing. This too would increase the flow as the rpm’s increase. But the water should be cool or at least close to the same as the outside water. This could be tested by filling the bildge well over the height of the bearing and starting the engine. Then water should leak out the bottom if is this assembly leaking.

Best of luck finding the issue. I’m looking forward to hearing what the issue is. It sounds like you have more than enough mechanical skill to fix the issue. Hopefully once found, it’s an easy repair.