10-20-2014, 01:58 PM #1
Went to winterize and found this.........
Well the lake was rather cool so decided to run the ski on the trailer in the water for a bit before changing the oil. However I see smoke coming thru the manifold area. I did not see a drop of water leaking in the hull and really could not see exactly where the smoke was coming from other than around the flex connection. Do you think my J pipe is shot or is something leaking in my manifold?
I went to flush coolant when I got home with the ski running and the engine came close to dying. After turning the flush off, it ran for 10 more seconds and died. It was hell to get it re-started. Finally it fired and starts fine. Could a leak in the J pipe cause water to backflow to the engine or perhaps its just water vapor that was sucked in?
10-20-2014, 03:49 PM #2
try to tighten that v-band clamp
how much gas is in the tank
10-20-2014, 04:13 PM #3
- Join Date
- May 2012
did you have the water running with the engine off? You might have filled the waterbox then backfilled the engine. If that's the case you may have hydrolocked the engine. If you hydrolocked it and forced it to start you will more than likely have a bent rod. I have a few sitting on the bench from people starting motors with water in them.
10-20-2014, 04:23 PM #4
Engine was running first before the coolant flush. When I heard the engine start to stumble I cut the coolant flush off and the engine was still running for about 10 seconds but idle was way low, it then died. It was hell to restart it though but when it finally started it acted fine. Only thing was the plugs looked like it ran way too rich and black. I read somewhere if the manifold has a leak at the J pipe it can suck water vapor back into the engine and foul the plugs. Not sure how much I believe that but I didn't find water in anything.
Back too the J pipe, do they split or crack at the flex area often? When I purchased this boat I noticed the water box and all was not aligned right and the flex area on the J pip was stretched way out on the top and showing nothing on the bottom. I shimmed the water box and go the J pipe even all around and I thought it was fine.
10-21-2014, 05:35 AM #5
Hummm I think something isn't quite right there! I don't think water caused that. I think it's just running rich for some reason!
Now I'm quite good with cars/ engines but I'm new to boats but check to see if you have a vacume leak! Maby inlet manifold or something. If these are anything like cars engines then that's normally the problem unless they have a faulty lambda sensor but I don't think these engines have them so I'm thinking vacume leak.
10-21-2014, 07:25 AM #6
how does the fuel system work on the twin motor set up
one fuel pump? high fuel psi will run rich
vacuum leak will not run rich, only cause a high idle
now a boost leak in the manifold could run rich
excessive blow-by can cause rich looking plugs
10-21-2014, 08:47 AM #7
Each motor has its own fuel pump. I noticed the last time out that same engine that use to rev perfect had dropped about 500 rpms or more at WOT and seemed to be surging a bit. Perhaps the exhaust leak is more noticeable at higher rpms and was choking the engine some? Maybe the idle control valve is bad? I recently reset the TPS on both to zero but that was 2 months ago.
10-21-2014, 09:39 AM #8
idle bypass/control only effects idle
all a exhaust leak will do is raise rpms and lean it out a tiny bit, never rich
10-21-2014, 01:23 PM #9
10-21-2014, 07:27 PM #10
- Join Date
- Feb 2012
One time I had oil over filled, and it was smoking out there. I think the oil was getting caught and burning which came out the "vent" looking area... It also ran rough when that was occurring.
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