Seadoo speedster 787 2 stroke twin engine

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Water sports

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Hi I am just querying my situation with the water raves on each muffler these are missing and have Been modified Do you recommend me buying two new ones and fitting these on the mufflers could this be one of the reasons my alarm went off continuously on the boat and they costly
 
It’s been quite a while since I looked at a stock 787 twin, but I’m pretty sure it had water con trip valves from the factory and was not hard jetted. If that’s the case, you will want to replace them, but go through your service manual and make sure every is routed correctly. It’s easy to get the lines crossed up.
 
They control when and how much water is injected into the exhaust. They have a big effect on both the cooling of the exhaust, and the tuning of the exhaust pulses at high rpm.
 
What year and model is your boat?
The valves can be replaced with jets but they clog easily. Without them you will burn out the exhaust hoses since they cool the exhaust.
 
What year and model is your boat?
The valves can be replaced with jets but they clog easily. Without them you will burn out the exhaust hoses since they cool the exhaust.
The boat is 1999 seadoo speedster 787 twin engine 2 stroke jet boat
 
So, yes yours had the water valves from the factory.

Here is how seadoo says to change to jets but they do clog easily.
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Remove the jets and verify they are clear. They are threaded in.
Ok will do can you please let me know which fitting has the Jet in, I gather this is similar to a carburettor jet using a straight (slot) screwdriver see photo below.


Also can You tell me what this unit is for this has completely burnt out and wondering if this is what turn the alarm on/buzzer. Any idea what would cause this I understand it's short but how when it was plugged in short
 

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It’s common for a rectifier to fail, but that’s one is really bad. It looks like an internal short to me, but I couldn’t tell you what exactly caused it. I don’t believe their is any fusing between the magneto and the rectifier, but I can’t think of any reason for the voltage to spike enough to fry one that way. Maybe someone else can chime in that’s see something similar before...
 
It’s common for a rectifier to fail, but that’s one is really bad. It looks like an internal short to me, but I couldn’t tell you what exactly caused it. I don’t believe their is any fusing between the magneto and the rectifier, but I can’t think of any reason for the voltage to spike enough to fry one that way. Maybe someone else can chime in that’s see something similar before...
What are these typically used for. Would a solar panel charging my battery cause this the one on the other motor looks to be okay
 
The rectifier takes the AC voltage from the magneto, and converts it to DC voltage that operates everything on the boat. It also regulates the voltage, so that there are no voltage spikes. A solar charger wouldn’t cause this problem. Something got either overloaded or was internally damaged inside the rectifier.
 
The rectifier takes the AC voltage from the magneto, and converts it to DC voltage that operates everything on the boat. It also regulates the voltage, so that there are no voltage spikes. A solar charger wouldn’t cause this problem. Something got either overloaded or was internally damaged inside the rectifier.
I did fit a airhorn on the boat without a relay
 
I don’t think that’s from accessories on the boat. It looks like the potting is melted around the stator wires. You may just have a bad rectifier and need to replace it.
 
The oil pump is easy to remove, it’s just a couple of bolts and then it pulls out. The plastic driveshaft may come out with it, so just make sure it goes back in correctly when you replace it.
 
The page I posted above 03-37 in Post #7 shows exactly where the jets are, in the brass fittings. You are going to have to pull the hoses off to see them.
 
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