JetSki idles at 3000rpm on start up

[GW1965]

Hi, Looking for help on idling problem with engine start up.
On dry start the engine cranks up to 3000rpm and revs scarily.
I am presuming it might be an air pocket or something in the fuel line??

I heard someone mention it as Throttle Shut off run or something along thos e lines.
When you give it some choke and release it a couple of times it generally falls back to 1000rpm as normal.
Can anyone answer as to what it is calles and whY it happens ?

Cheers

 

[Dr Honda]

Since you are saying it comes down to 1000 rpm... I'm assuming that this is in the water.

If it is... and it runs well after it warms up... I would say to check the high and low needles on the carbs, and look for an exhaust leak.

If that all checks out... just run it a little longer with the choke.

Over the years, I've had a few skis that would run fast until they warmed up a little.

 

[GW1965]

Cheers Dr Honda. Thx for your reply.
I have only found it happening at present on a dry start out of the water.
As it occurred when flushing out & quick engine runs.
I was a bit nervous to run it in the water until I had more info on what it might be and why it happens..
When i activate choke after start and release once or twice it seems to settle at normal idle..

I've since heard that it is not likely to happen under load when in the water . Is that so??


Thx

 

[Dr Honda]

Yes... some Seadoo engines will "Run away" when not loaded. It has to do with being a little lean. Sometimes opening the low screws a little will help.

When the pump is in the water (not on a hose) it won't run away.

 

[manolocross]

Normal idle speed out of the water is 3000 rpm for the 95 seadoo xp(720 engine)....in the water it should drop the idle down to 1500 rpm so if its dropping to 1000 rpm out of the water the engine will never stay on...in the water