94 750 slt won't start.

[Crenche]

Hello all. I have been lurking on this forum for quite a while now and this past February I purchased a 94 750slt for $460. At the time it would run a little bit but diving further into it I found some problems with the ski. The fuel restrictor was missing so I tried to fashion one but was poor attempt. I have always had a hard time starting the ski. To make a long story shorter I ended up rebuilding the carburetors. I have placed them back on the ski and the thing will not start. It keeps turning over and over but no fire. It know it has spark when I pulled the plugs and I can see the spark. It has the triple outlet fuel pump all fuel lines replaced (including inside the tank). I have the 90 jet restrictor tapped into the return nozzle on the last carburetor. The compression on the engine is not so good, about 115 on all three. No holes in the cylinders. The crank is not out of alignment according to the pencil method. What am I missing? Battery is fully charged. Lanyard is in the correct place. I cannot figure this out.
The only 2 things that I'm thinking is that (1) either the plugs are fowled up (2) there is not a good seal on the manifold letting fresh air in and making it too lean.
I have done everything that I know how to do and all that I read. I'm at a dead end.
Can anyone help me with this. It is driving me nuts.

[BryanP]

Try dumping some premix down the carbs and see if it fires. Sometimes the fuel pumps dont like to prime themselves.

[nick072010]

Did you rebuild the fuel pump, if not its only a $20 kit and its cheap insurance for your motor. If you got spark then its a fuel issue there are no valves on a your 2 stroke so spark and fuel equal boom! Did you get new gaskets for your carbs and reeds, i would do that to or at the least do a leak down to make sure you dont have a leak.

http://www.ebay.com/itm/Polaris-650-750-780-Intake-Gasket-Kit-/250879909811

Contact this guy for the fuel pump re-build his name is John Zigler has pretty much anything you could want for your ski and he has a lot of good advice.

WATCON.COM
211 Glen St. Janesville WI 53545
Phone: 608-743-1305

I am not sure how familiar you are with Jet Skis so this may be a wealth of knowledge for you or a bunch of stuff you already know but anyone learning about Polairs skis with Fuji Motors should read the entire page.

https://sites.google.com/site/polari...is-fuji-engine

Welcome to greenhulk and trust me your going to get the help you need here these guys are great!

Also one last thing, when you went through the carbs did you make sure your high jets and low jets were set right?

[xlint89]

Verify your hose routing is correct. make sure the pulse hose is on the correct fitting. http://www.greenhulk.net/forums/showthread.php?t=15433

Try the premix as Bryan said. it does help to prime the fuel lines much faster than try to pull fuel all the way to the engine from the tank by just cranking.

And welcome to the Hulk.

[Crenche]

Did you rebuild the fuel pump, if not its only a $20 kit and its cheap insurance for your motor. If you got spark then its a fuel issue there are no valves on a your 2 stroke so spark and fuel equal boom! Did you get new gaskets for your carbs and reeds, i would do that to or at the least do a leak down to make sure you dont have a leak.

http://www.ebay.com/itm/Polaris-650-750-780-Intake-Gasket-Kit-/250879909811

Contact this guy for the fuel pump re-build his name is John Zigler has pretty much anything you could want for your ski and he has a lot of good advice.

WATCON.COM
211 Glen St. Janesville WI 53545
Phone: 608-743-1305

I am not sure how familiar you are with Jet Skis so this may be a wealth of knowledge for you or a bunch of stuff you already know but anyone learning about Polairs skis with Fuji Motors should read the entire page.

https://sites.google.com/site/polari...is-fuji-engine

Welcome to greenhulk and trust me your going to get the help you need here these guys are great!

Also one last thing, when you went through the carbs did you make sure your high jets and low jets were set right?

Im not sure that the high and low jets were set right. I just used the jets that were already in there and didn't mess with the jets. I just replaced the diaphrams and all the other small pieces. After I rebuilt the carbs I did pop off testing and they all popped off about 15 psi which is within limits for my ski.

I have done a leak down test before but I can't remember if it was pre or post manifold extraction. Looks like I need to do another one. Had a hard time sealing the intake manifold with the raquet balls.

When I put the manifold back on the ski the original gaskets were toast so I bought the gasket material from Autozone and made my own. Maybe that wasn't such a good idea??

I know the fuel pump is pumping fuel because I have disconnected the fuel lines to the carbs and turned the engine over and I saw the fuel come out of the pump plus I have a primer pump connected to the fuel hose from the fuel tank. To make sure that I wasn't getting any air into the system I have bypassed the water seperator (for now) just to get the ski running. I believe the pump is relatively new maybe a couple of years old.
I will try the premix on Friday when I get the chance. Gotta work the next couple of days.

[BlueFishCrisis]

I found the 90 jet to be too large for your custom restrictor. Did research a while back and if memory serves the closer jet size is 60 to the stock restrictor. May want to change that too......

[Crenche]

I found the 90 jet to be too large for your custom restrictor. Did research a while back and if memory serves the closer jet size is 60 to the stock restrictor. May want to change that too......

That could be the problem. That is very interesting. I will have to order another jet then.

[nick072010]

You might want to go ahead and get a triple output pump if you dont already have one, and I phrased it wrong last time, I meant to ask have you checked and adjusted the high speed needles. When I rebuilt my ski I had to dump premix to get the motor to fire and draw enough fuel in to the lines just FYI. Good Luck

[Crenche]

You might want to go ahead and get a triple output pump if you dont already have one, and I phrased it wrong last time, I meant to ask have you checked and adjusted the high speed needles. When I rebuilt my ski I had to dump premix to get the motor to fire and draw enough fuel in to the lines just FYI. Good Luck

I already have the triple pump fuel pump and it pumps fuel. I tried pouring premix down the carbs and it was a no go. So I assume it is a spark problem? Am I correct in that assumption? I see spark when I take out spark plugs and try to start with out the plugs in. Do you guys think that I need to go ahead and try new plugs in it? When I pull the plugs they are wet with fuel.
What else am I missing?

[BryanP]

I would try new plugs. Also try trimming the plug wires back 1/4 inch. There may be a bad connection with the plug boot.