Ski won't start

[JS440Patnode]

I bought a JS440 off of a guy and it started great when the battery was jumped. Now when I charged the battery fully, it won't start. It cranks over but doesn't start up. I'm getting spark, but the fuel doesn't seem to be getting pulled to my carb and Pistons. I'm hoping that it's a simple fix, any ideas?

 

[Fleabags]

Since you don't know the history, its tough to diagnose without going thru the basics so you know what you got.
I would:

Check compression
Check fuel lines for leaks
Check pulse line
Clean and rebuild carb - I'd highly recommend it, since you might end up chasing your tail if you don't.
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Does it crank over fast and strong? I remove the choke and install a primer on all my skis, nothing beats a quick burst of fuel in the carb.

 

[JS440Patnode]

My compression is 120 in both, all of my lines don't have leaks, my carb is clean but I don't have a primer kit.
I have spark plugs that aren't for the jetski but they get spark, could that be a problem?

 

[JS440Patnode]

My compression is 120 in both, all of my lines don't have leaks, my carb is clean but I don't have a primer kit.
I have spark plugs that aren't for the jetski but they get spark, could that be a problem?

And it does crank fast and it seems strong.

 

[Fleabags]

Okay, you have ruled out worn cylinders/pistons, which is good. And yes, the right plugs matter. Spend $5 and put the right plugs in it, then focus on the carb. I know you said it's clean, but does it pull fuel? As you know, the fuel pump is built in and the diaphragm pump can become weak if it is old, gummed up, torn, etc. A crude why to test your diaphragm pump is to remove the "IN" line from your carb. Take a small glass jar of fuel and run a fuel line from the jar to the carb. and crank it over. It should pull fuel from the jar. Use a clear piece of hose so you can watch it. Also, confirm your fuel lines are configured correctly.