1994 sea doo spx problem

[Jimcut]

Hi Guys,

I'm new at this and need some help

I have prepared my jetski and in garage works quite fine

I took it down in thw water and at idling speed works fine but whe you throttle the unit it will not go. It feesl bogged then when it feels up to it works fine for a couple of second and bogs again. No power at all.

Any ideas if the prblem originates from the carb or fuel pump or oil/fuel misture

Please help

Thanks

 

[Bills86e]

Insure the 657X engine has BR8ES *plugs gapped .021. 99% of these ski are fuel
system related. Check compression, should be around 150psi. Next, remove the
supply & return lines from carburetors. Air chuck a few lbs (5-10) and see if fuel
comes out into a catch pan or bowl. Smell it. If does, & smells like clean fuel, put
a 2' clear tube filled with pre-mix gas attach to supply side of carb, start engine or
see if it drinks fuel and routes thru carbs. Gas goes bad in 3-4 weeks, then goes
through a chemical change that is irreversible. Use of STABIL in good gas can keep
gas in a stored ski good up to 6 months. Pre-mix Gas in *holes & down carbs may
help inital start-up. Hope this helps! Bills86e

 

[Jimcut]

Hi many thanks for your reply. It helps as it confirms what we think we have to do.
Fuel is just put in , so it should not be a problem from that end. The other works suggested are all going to be done to ensure that is working OK too....
From my understanding it seems that the problem is the fuel system, I will check the fuel pump, pipes, and remove and rebuild carb....
Please confirm if I am on teh right track and if you have any hints for me!!

Thanks
Jimmy

 

[Bills86e]

Yes. The lower case nipple to the carb fuel pump transfers a piston's pressure & vacuumn (called pulse) to the pump diaphram, that must Draw/suck fuel from the
tank (called Supply side), then push the pressured gas thru carb(s) and back to tank (called Return side). And air allowed in the supply side, or a clog anywhere
will prevent the fuel from its circulatory routeing. A torn, cracked leaking diaphram
or a water droplet in the carb oriface holes can prevent carb from metering the fuel.
dirt, grit, or particals in the carbs micro-filter can halt metered flow. Even a small
loss of flow can seize an engine (called LEAN condition) too much air, not enough fuel.

 

[Jimcut]

brilliant, we have removed the carbs and found the micro filters completley clogged, one was 100% clogged and the other 10% open, so it was running on idle but when when when increase throttle it was bogging.... many many thanks will rebuild and test!! hope all is well now!!!

 

[sketchpad]

since you're rebuilding your carbs make sure you replace you fuel lines from the grey if you still have them. and clean your selector, otherwise you'll just end up with the same problem again.

and u may as well check your compression...mine was both fuel and compression