1999 Seadoo speedster jet boat

[Water sports]

Questions

Question 1 -Can someone tell me what this unit is for, this is located under the boat towards the front I have noticed this looks to be damaged and are concerned that this will have an impact of the boat,



Question 2 - I am reinstating the four rave valves and are wanting to be 100 percent these are correctly installed Flat face pointing away from the head With curved Bevel towards the head/motor.


Question 3 -Grey fuel lines, I understand the grey fuel lines are deteriorating on the inside causing carburettor problems, are these lines typically just on the carburettor.


Question 4 -I am very keen to get my hands on a full service manual for my Seadoo Speedster 787 twin engine 2/jet boat,


Question 5 - There are two screws located just above the bottom of the motor and a wondering what these are for as my motors are two stroke

 

[Ankeneyou]

1. Looks like a scupper valve but i dont recall one being stock on my 98 in that spot.

2. If the valves are OEM, they should clearly say TOP on the end that faces the top of the engine. The curved face goes down.

3. There were no gray fuel lines on the boats, they should have had very thick walled marine rated lines. It looks like someone already swapped for regular automotive lines looking at the fuel pump in one of your pics.

4. Here is the 98 manual, they are basically the same boat.
https://drive.google.com/file/d/1Us1Mvv5OpCvnAwhoRF1GoHnF8hc7iw0p/view
5. Im not 100% sure what you are referring to without a good pic. If you are seeing the slotted plug on the crank case, its for filling the counter balance shaft cavity with oil.

 

[mikidymac]

The plug is for the balancer shaft not the rotary gear.
You don’t need to do anything with the balancer shaft oil unless you get water in the engine.

 

[Water sports]

Do you think I should unscrew it and check if there is any water in the oil or what the oil looks like and if I have water or the oil looks not to an acceptable state how do i drain it

 

[Ankeneyou]

Haha, yeah my bad i meant counterbalance shaft.

 

[Water sports]

Hey could you confirm that the blade is the right way around for installing the rave

 

[Water sports]

Or do you mean like this

 

[Ankeneyou]

First pic is correct. TOP should be pointing towards the spark plugs.

 

[mikidymac]

In your last picture the valve is in the housing wrong.

The blade should say “top” pointing towards the spark plugs. But the housing should have the cutout pointing towards the exhaust manifold.

 

[Water sports]

Ok great could you kind enough just Finally confirm by the this new photo, Sorry don't mean to be a pain but just want to get this right

 

[Ankeneyou]

Correct. Looks like you need a new temp sensor also.

 

[Water sports]

LOL, Yes thank you I have bought two new ones on that subject do these need to be locked tighted or do I just screw them in this is relation to temperature sensors

 

[Water sports]

Haha, yeah my bad i meant counterbalance shaft.

So are you saying this unit under the boat is for The counter balance shaft ? Keen to know what this is for and if i need to replace it. It looks like the material inside it is dripping down but its hard.

 

[mikidymac]

So are you saying this unit under the boat is for The counter balance shaft ? Keen to know what this is for and if i need to replace it. It looks like the material inside it is dripping down but its hard.

No, that is not the balancer shaft.
It is some kind of water drain or inlet.