1993 spx wont stay running

Not open for further replies.


New Member
I have a 1993 sea doo spx. I've owned it for a few years and its always ran, but had little problems running here and there. Some carb tweaking worked in the past. Last year it was running fine, then started to lose power and not accept throttle and bogged down to the point where it wouldn't restart in the water or on the trailer. So now I'm working on it. I figured the carbs needed to be rebuilt. I did that and did get alot of gunk out of them. Put them back on and it still wouldn't start. Messed around with it for a while and it will start and run if I feed gas directly through the carbs or in the spark plug hole, but it won't run by itself. Gas is getting pumped into the carbs. I even took a gas can with brand new gas and a new fuel hose and it wouldn't run off that either by itself. All hoses are clear. Compression is about 155 in both cylinders. Needle and seats are not sticking. I'm not sure where to go from here. Hoping someone can help!
It sounds like you are fighting a carb problem if putting gas in the cylinders fires the motor off.

Compression sounds good but a hair too high which makes me think you should try another, good quality, compression tester just to confirm and get a "second opinion".

First question. Did you use original mikuni parts and rebuild kit when you rebuilt the carbs? If you did not use original Mikuni parts then order all new rebuild kits with Mikuni needles and seats and redo the carbs right now. Aftermarket carb kits will let the machine run, but will not let it run right and give you constant trouble.

Does the machine still have the grey fuel lines in it? If it does replace all of them with 1/4 fuel line, automotive grade, black napa style, not high pressure.

After you replace the lines go back into the carbs and clean them.

Did you follow the carb rebuild thread at the top of this two stroke section? There are small passages and holes that ALL NEED TO BE CLEAN in order for the motor to operate properly. A can of crc brake clean with the spray tude to focus the cleaner in the passages, a good air compressor with a rubber tipped nozzle are needed. Follow that rebuild thread, it is the best step by step guide for carb work you will find.

Make sure the pop off pressure is set properly.

Replace the fuel selector valve with an OEM valve, they can leak air snd give you trouble.
It does have black lines, but i didn't use mikuni brand parts. As for the fuel valve, I didn't know that could be an issue. I will order that valve and a new rebuild kit and I will follow that thread for the rebuild. Thanks for the tips! Hopefully that solves my issues
Your issue is the non-Mikuni parts. Every time, that is the issue. You are going to have to do the carbs again using only Genuine Mikuni parts.
Alright, i put a new valve in it and rebuilt the carbs again with the mikuni parts. I even put a new fuel line on it. I added a clear fuel filter and it appears im not getting gas through it. Do i need to manually prime the fuel system since i had the lines out? What would be the cause of no fuel getting to the carbs?
Do not use aftermarket fuel filters. You can put a little premix down the carbs to get it to fire and start pulling fuel.
NOT trying to be a smart-ass or anything like that....but you routed the fuel lines to the right ports on the fuel selector AND the fuel selector is ON (don't laugh....I once had a fuel problem that was giving me fits until I "noticed" the fuel selector was in the OFF position.....as he hangs his head in shame).
Not open for further replies.