Seadoo speedster jet boat

[Water sports]

Front (MAG) carb
Main 140
Pilot 67.5
High speed screw 0
Low speed screw 1-1/2

Rear (PTO) Carb
Main 142.5
Pilot 67.5
HS screw 0
LS Screw 1-1/2.

The rear (PTO) carb without the fuel pump only uses the rubber o-ring, no paper gasket.

Hi I am a little confused on the positions of the carburettors I have shown you a photo of the carburettor sitting on the motor the fuel pump is on the rear not the front so I guess this alters where the jets sit in the way of 140 and 145. Also the carburettor with the petrol pump also does have no gasket only the diaphragm

 

[Ed Dozois]

Hi I am a little confused on the positions of the carburettors I have shown you a photo of the carburettor sitting on the motor the fuel pump is on the rear not the front so I guess this alters where the jets sit in the way of 140 and 145. Also the carburettor with the petrol pump also does have no gasket only the diaphragm

That is accelerator pump on pto carb

 

[Water sports]

That is accelerator pump on pto carb

Okay right so my fuel pump is not actually on the carburettor then.

 

[mikidymac]

No.
The front carb even in your picture above is the (MAG) or magneto carb and is at the front of the engine. THis carb houses the fuel pump which is built into the side of the carb and has two round mylar check valves in it .

The rear carb in your picture (PTO) Power Take Off where the driveshaft connects does not have a fuel pump.
The plunger and spring you see on this carb is the accelerator pump, not the fuel pump. THe accelerator squirts a burst of fuel when the throttle is opened to make the air/fuel mixture richer for acceleration while letting the base jetting stay lean so that you do not foul spark plugs during extended idling and emissions reasons.

 

[Water sports]

Okay right so my fuel pump is not actually on the carburettor then.

Is this the petrol pump, if so do you recommend reconditioning them

 

[Water sports]

Hi there is no fuel pump that I can see on the carb at all, I had sent you a photo I believe the fuel pump is separate to these carbureted can you please confirm I am on the right track I do appreciate your advice

 

[Ed Dozois]

Hi there is no fuel pump that I can see on the carb at all, I had sent you a photo I believe the fuel pump is separate to these carbureted can you please confirm I am on the right track I do appreciate your advice

Yes,This is fuel pump, different than the skis but I'm sure the parts that came in carb kit are same. I'm sure one of the great folks here will confirm. Read Mikidymacs carb rebuild thread here.

 

[mikidymac]

Yes, on the boats the fuel pump is separate. So your MAG carb just gets the shaped o-ring and the filter.


I would also change that fuel filter in your picture as it looks like it has never been done.

 

[Water sports]

Mikidymacs carb rebuild thread here.

Mikidymacs carb rebuild thread here. No link attached

 

[mikidymac]

Mikidymacs carb rebuild thread here. No link attached

CARB REBUILD THREAD

 

[Water sports]

Yes, on the boats the fuel pump is separate. So your MAG carb just gets the shaped o-ring and the filter.
View attachment 46902

I would also change that fuel filter in your picture as it looks like it has never been done.

Okay thanks yes I have brought new line filters to fit, In regards to that just wondering on one of the outlets the arrow faces each other and on the other side Arrowpoint the direction of the outlet which pipe goes on which

 

[mikidymac]

Just follow the arrows at each nipple. The one going into the filter is from the petrol tank and the one going out goes to the carbs. Disregard the one that is molded shut.

 

[Water sports]

Hey thanks for all these answers this is absolutely magnificent I’m so glad I found it you guys are a massive big help to me is in Auckland there’s not a lot of people that want to work on these boats because they are 2/ but the boat is actually in very good condition and did run brilliantly until that alarm went off hence why I am reconditioning and servicing the boat myself with your answers
Do you know how I can exactly determine my boat model so I can download a proper manual for it with my carburettor for example inside this service manual. In the club downloads

 

[mikidymac]

@hfgreg might be able to help with the manuals and boat ID.

 

[Water sports]

@hfgreg might be able to help with the manuals and boat ID.

Great thanks for that I will get in touch with him I have just sent a request
. also in your knowledge is there any information on the reconditioning of my fuel pumps and I think yourself or somebody said the gaskets may fit that I have in the carburettor kit

 

[Water sports]

I am really keen to get my hands on a Seadoo Speedster 787 jet boat twin engine 2 stoke 1999 service manual please help

 

[Water sports]

Just wondering if anybody has two temperature sensor top plugs for sale for a seadoo speedster 787 jet boat as I am missing both these plugs

 

[mikidymac]

Just wondering if anybody has two temperature sensor top plugs for sale for a seadoo speedster 787 jet boat as I am missing both these plugs

Contact Nick or Jess at Westside Powersports Seadoo.

 

[Water sports]

Can someone tell me what this unit is for, under my jet boat on the bottom side of the hull

 

[Water sports]

diaphragm on the muffler water regulator

How do i check these and where are the located (diaphragm on the muffler water regulator )

 

[Water sports]

Just follow the arrows at each nipple. The one going into the filter is from the petrol tank and the one going out goes to the carbs. Disregard the one that is molded shut.

Hi, i am looking at connecting the new filters up tomorrow and still are not clear on the pipes direction in and out on the filter showing in the photo. would you be able to tell me what side of the filter pipes are coming in.

 

[mikidymac]

 

[Water sports]

That hose should be soft and they don’t go bad.

That’s the hose you put the shutoff valve on but you have to remember to always turn it on. Some people put the lanyard on it so they don’t forget.

This is all I can find I can't actually see a photo from our discussion on this the shut off valve I put on the oil line is from the oil container to the bottom of the engine is not the pipes running to the Oil pumps ?

 

[mikidymac]

This is all I can find I can't actually see a photo from our discussion on this the shut off valve I put on the oil line is from the oil container to the bottom of the engine is not the pipes running to the Oil pumps ?

No not the ones to the pump.