SPX Won't Turn Over....

[SPX-Smitty]

SO I am new here as far as being regestiered, but I have been surfing through this website ever since I brought the 96 SPX a couple of months ago.

Because of those read throughs, I have so far: Cleaned the Carbs, Replaced the Fuel valve, Replaced the fuel Filter, and the latest being that I Replaced the old grey Fuel Lines and installed all new lines.

Now, this is where I think the problem stims from. In replacing the fuel lines last night, I think I basicly eliminated the fuel that was in the lines, and therefore when I go to start it today, I don't think it is getting any fuel. When I pulled it out to give it the dry start, it started and ran for about 45 seconds or so then cut off. Started it again, and it did the same. Now... it won't turn over at all. So I stoped trying and came here to ask if I should have some how purged the lines, or filled them with gas before doing that?

Thanks! Once I get this problem solved its on to replacing the carbon ring, Yay.

 

[JPX]

The fuel eventually blows itself through the lines as long as the MAG carb's fuel pump is working correctly - check valves, diaphragms, etc.


The system is also sensitive to pressure leaks - this includes look hose clamps, missing spin-on filter gasket, and faulty check valves.

 

[SPX-Smitty]

In order for the fuel blow itself through the lines do I need to continuously try to start it, or do I just leave the fuel valve open and let it sit for awhile and try again?

I tried multiple times today and started to get worried about my battery either dying or burning out the starter all together.

I'll check the clamps one more time, and make sure there is a good seal on the fuel filter, any other advice would be appreciated!

Thanks!

 

[steve10391]

and the latest being that I Replaced the old grey Fuel Lines and installed all new lines.

Make sure your lines are correct. Its easy to get them connected to the wrong place. If your fuel pump is working good you should have had fuel to the carb in less than 20 seconds. As far as your starter goes I wouldnt crank it for more than a minute at a time with a 10 mminute cool down period after each attempt.

 

[SPX-Smitty]

Alright so I am back... same problem. I double checked the fuel lines to make sure everything was connected firmly, and in the right place, and everything checked out. I took off the one of the main fuel lines that end into the carbs to see if there was any gas in it and there wasn't. I also took off the fuel filter cup to see if it was full of gas and it was not.

Seems like now I have a fuel pump problem, but my question is why was it working before just fine and now that I have changed the lines out it doesn't work. Is the fuel pump not required if the lines are already filled with gas? It just confuses me that it was working on the water a couple days ago... minus the bog downs, and now the lines won't fill up with gas.

Any help would be helpful! Thanks!!

 

[robin savell lloyd]

I have noticed that when you have a fuel pump problem the fuel pump will work some what ok as long as there is gas in the line to it and in it. but if it has to suck air at first it may not be able to prime it self. A full tank of gas has made this problem go away some times and some time I have just added a small amount of air pressure to fuel tank to help it out. but you should not have to do any of this if every thing is correct. :cheers:

 

[robin savell lloyd]

I noticed you say it bogs down. have you gave it a compression test? if the cylinder that gives the fuel pump pulse is low on compression you will have a hard time pumping fuel.:cheers:

 

[SPX-Smitty]

Sorry if this is stupid question but the fuel pumps aren't electrical are they? They didn't seem to be hooked up to anything that looks like electrical wiring. So that brings me to my next question, how exactly they work.

Anyway, I am going to head down to the local 7-11 and fill the tank up based on your advice. I am willing to try anything right now.

Do you think there is anyway to siphon the gas through the lines? In other words prime the lines?

 

[SPX-Smitty]

I noticed you say it bogs down. have you gave it a compression test? if the cylinder that gives the fuel pump pulse is low on compression you will have a hard time pumping fuel.:cheers:

Yes I had a compression test done when I bought it, and both cynlinders matched perfectly. I don't remember the exact number but 145 comes to mind in both cynlinders.

I also had the carbs cleaned a couple weeks ago and that made the problem better, but it continued to happen... especially when the fuel valve was in normal mode. The turned the valve into res and it worked much better. Which lead me to where I am tonight. Replaced the valve, lines and fuel filter (which was nasty) to solve that problem but now... my lines have no gas therefore it doesn't start.

<sigh> toys.

 

[JPX]

I can't wait to hear what happens next! I hope once you get some gas in there this thing fires!:grouphug:

 

[robin savell lloyd]

Did you make sure that your water seperater [filter] oring was in place if it has one and that fuel was coming out of the fuel selecter valve?

 

[SPX-Smitty]

If you are refering to the fuel filter cup, when I took it off the o-ring stayed in place. I was told that if it did stay in place, that it could be reused. So that one is there and I am assuming snug.

As far as seeing if there was any fuel coming through the fuel selector valve, I don't really know how I could do that. Any suggestions? I am about to get started working on it again today.

 

[JPX]

You could disconnect a fuel hose at the baffle - one of the hoses that runs from the selector to the tank.

Then stick that hose into a small soda bottle of gas. The bottle would simulate the fuel tank. Then try to start. If the fuel gets sucked out of the bottle, you should be able to see it.

But with all that going on, you might as well remove the valve completely and blow it out with compressed air. You'll need replacement hose clamps if the factory ones are on there.

 

[seadoosnipe]

Wow, ....?

Man, seems like a little prob with the grey lines has led you to a nightmare. The only fuel pump on your ski is a pulse line type. On your mag carb, you have a hose connected to the middle nipple. That's the pulse line. That line should run down to the engine block, right in front of the MAG cylinder.

Take that short piece of line off the mag carb. Put your thumb over it and turn the engine over. You should feel it pulsing, sucking in, pushing out. If not, then remove that hose and blow through it, to make sure it is clear. If it's clear, you may want to check the clear plastic diaphragm inside the MAG carbs pump housing. This clear plastic diaphragm undulates with the rythm of the motor rpm. The two check valves open and close at the proper times to keep the fuel circuit full of fuel. When the motor is running, the fuel is constantly running in a loop from the gas tank, through that pump and check valves, then back to the tank. The fuel is used when the throttle plates are open and exposed to the venturi effect, which is what sucks fuel into the carbs.

The carbs work on vacuum. There is no pressure driving the fuel into the engine. That pulse line pump only ensures there is fuel to the valve body. When the throttle plates are open, the diaphragm pushes in on the arm and spring, allowing fuel to be sucked into the low speed jets.

I have a thread called "Snipes Korner" and the first few post are dedicated to the operation of these carbs. They truly are simple carbs. Here's a link to my thread if you'd like to read up on them. http://www.seadooforum.com/showthread.php?t=4151

I'm also going to send you a PM, for a bit of "shade tree" mechanic'in that might help you out.

 

[SPX-Smitty]

Well no good news yet guys. Thanks for all the help and trust me I am using it.

I took apart pretty much everything I was comfortable taking apart today and that mostly was the fuel pump and all the lines in and around the carbs. Everything seemed really clean, and none of the holes or lines were gunked up or anything. I did pull out the small fuel filter in the carb and cleaned that. It wasn't dirty enough to stop fuel from flowing through it.

I haven't done the thumb test that snipe suggested, because I just saw his post now. I might try it in the morning, but at this point through I was really considering taking it to a shop I know, and having them fix this and do a couple of other things like replacing the carbon ring and the wear ring. So we shall see.

Any other suggestions would be awesome through. Nothing makes you learn about something more then going through something like this. Before I know it I'll be an expert on the SPX! :cheers: