flooding superjet

Johnson8537

Johnson8537

Superjet Rider
Location
Medford, Oregon
Ok guys I picked up a 93 SJ (6m6/61X combo) over the winter and on the trailer if I forget to turn the GAS off and go to start it- it will crank and not start ( After pulling the plugs it is EXTREMELY flooded. I have to dry the plugs out and crank the engine over a few times to get the gas out.) it also did this yesterday after about 10 mins in the water.
(If i turn the gas to the off position NO issues at all?)

It has been bad enough before that it BLEW UP the water box (GAS OIL MIX in H20 BOX when it fired off exhuast must have had a flame/spark and egnited it?)

Anyway on to the question.
What do I need to do to fix this flooding issue. ( I would like to be able to leave the gas on because I don't want to get stranded if I happen to forget to turn it off.)

Is it a bad Petc0ck? (the boat also has a primer.)
Or is it a carb issue? (bad Needle/seat or float out of adjustment)?
Bad Check Valve??

Thanks in advance guys!
 
ger87410

ger87410

How did I get here?
Location
Fort Worth
Replace the needle and seat.

Gas doesn't flow at all on these things without the engine running. They don't have petcocks.
 
Johnson8537

Johnson8537

Superjet Rider
Location
Medford, Oregon
ger87410 said:
Replace the needle and seat.

Gas doesn't flow at all on these things without the engine running. They don't have petcocks.
Click to expand...


petcock=gas selection ON OFF RES

Thanks... What Carb would I have on my SJ SINGLE Mikuni 44?? (That way i get the correct parts?)

I have never rebuilt a pwc carb just ATVs Does it only have one needle and seat? anyone have any part numbers?

should I replace the springs too to make sure my pop off is correct? SKI RUNS AWESOME other than the flooding issue. ( I dont have a tester so i would just be replacing them.)
 
ger87410

ger87410

How did I get here?
Location
Fort Worth
Probably just the needle and seat.

Pull the hood and look at the carb. Only way to be sure if you have 1 or 2. Measure the opening in mm to get the model, and look for a branding on the side for the make. Post pics of the carb if you are still unsure.

Get a complete rebuild kit that has the needle and seat. These are the easiest carbs to rebuild. Way easier then a 4-cycle.
 
SUPERTUNE

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Use Mikuni brand only rebuild kits SBN 38/44/46 and then you buy the needle valve extra depending what size you have or need.
Take out what you have for a needle valve and look on the bottom and is stamped the size, could be 1.5, 2.0, 2.3, 2.5 are the most common ones.
If it is stock size it will be a 1.5. Sometimes I do use bigger ones like a 2.0 or 2.3 for hot rodded engines setups. Use the same size to keep the jetting the same as it is now.
Use the same spring UNLESS you define EXACTLY what gram rated spring you have!
The new Mikuni kit will come with 2 of the 4 springs that are available, so be careful as to know what your doing if you use one out of the kit as it might not be the right one you have in there now.
If you use the new float arm in the kit set it level using a single edge razor blade.
 
Johnson8537

Johnson8537

Superjet Rider
Location
Medford, Oregon
SUPERTUNE said:
Use Mikuni brand only rebuild kits SBN 38/44/46 and then you buy the needle valve extra depending what size you have or need.
Take out what you have for a needle valve and look on the bottom and is stamped the size, could be 1.5, 2.0, 2.3, 2.5 are the most common ones.
If it is stock size it will be a 1.5. Sometimes I do use bigger ones like a 2.0 or 2.3 for hot rodded engines setups. Use the same size to keep the jetting the same as it is now.
Use the same spring UNLESS you define EXACTLY what gram rated spring you have!
The new Mikuni kit will come with 2 of the 4 springs that are available, so be careful as to know what your doing if you use one out of the kit as it might not be the right one you have in there now.
If you use the new float arm in the kit set it level using a single edge razor blade.
Click to expand...

Does it sounds like I need a complete rebuild or just replace the needle and seat?

I am just trying to figure out why it would continue to flood the engine with the petcock in the ON position.
 
SJBrit

SJBrit

Extraordinary Alien
Location
Bradenton, FL
Fuel will siphon into the engine if there is a path. Your problem is a leaky needle, so that means a new needle and seat. If that is leaking chances are that the rest of the carb(s) could do with some attention too. While you have it apart you may as well do the full rebuild - it's a pain to pull them off and dismantle them, so while you're in there....
 
SUPERTUNE

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Your talking about a 15+ year old carb!!
So yes do it once and be done with it!!
The rubber parts are pretty shot by now and the way gas is today with all of the ethanol in it, it's a good idea so it will be good for awhile.
 
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