fx1 fuel delivery problem

Location
FL
Trying to help a friend of mine get his fx1 running. Rebuilt carb, replaced fuel lines, drained and refilled fuel tank (there was water in it). It will start and run if you pour gas into the carb but does not seem to be sucking gas on its own. Any ideas?
 
Location
FL
Should I be able to feel any air coming out of the pulse fitting on the intake manifold when I crank the motor, because I don't feel anything.
 
Location
FL
I pulled the carb completely apart again. I am going to clean it thoroughly and reconnect all of the fuel lines making sure everything is tight. It does seem to be sucking a very small amount of fuel. It has to be a simple problem that I over looked.
 
Location
FL
Reassembled everything and got the same result. I figured the only thing I had not checked was the one-way valve coming off the tank. It seemed to function ok when blowing into it, but I figured maybe it was bleeding off pressure in the tank causing the lack of fuel pressure. I took the valve off and blocked the vent line off and that did it. The ski ran and idled on it's own. Now, does anyone know what PSI one way valve I need to buy to replace it?
 

Mile9c1

X-H2O.com
Location
Grand Rapids, MI
That might not be your problem. You should be able to run with that vent missing (ie no pressure control in your tank). It's only job is to not let gas/vapors escape the gas tank. But it will allow air in... at least that's what I think.
 

Jumper

What! What!
Are you getting fuel in the main filter? Not the internal filter in the carb. I wonder if you have a vapor lock or something in the feed line. I know you took the carb apart again. I wonder if you got a gasket or something in there upside down or backwards or something like that.

Oops, just realized you got it running. I agree with Mile. I don't think you can run with the vent blocked off. That valve is a pressure relief valve. If it gets blocked pressure will build up in the tank, and the engine will not be able to pull fuel against the greater vacuum in the tank. So, normally the engine will run for a few minutes until the vacuum in the tank builds up, then will die from fuel starvation.
 
Last edited:

ANT

Just ride
Reassembled everything and got the same result. I figured the only thing I had not checked was the one-way valve coming off the tank. It seemed to function ok when blowing into it, but I figured maybe it was bleeding off pressure in the tank causing the lack of fuel pressure. I took the valve off and blocked the vent line off and that did it. The ski ran and idled on it's own. Now, does anyone know what PSI one way valve I need to buy to replace it?

I think they're 3psi. buy a stocker
 
Location
FL
Tried it with my check valve from my superjet. The ski will run on its own now, but it is still starving for fuel. If you don't rev in constantly, it will die. When I pull the fuel line off, there just doesn't seem to be much fuel that comes out. The fuel filter also does not fill very much at all.
 

Jumper

What! What!
Did you accidently reverse any of the fuel lines? The return or main or reserve? You might try bypassing the fuel cutoff switch also. Sometimes those get snarky. I would check those first. You might also need to adjust the idle speed and low mixture screw.
 
Location
FL
The fuel lines are on correctly. Fuel switch is already bypassed. Richening up the low speed screw actually makes it run better. However, this is only compensating for the problem because there is not enough fuel getting to the carb in the first place.
 

LBE

Eddie Would Go.
Location
Charlotte, NC
The fuel ine comming in to the carb goes in the bottom, return line to the nipple. Just FYI, this has solved problems on a couple skis I have worked on. double check.

Make sure there are no tears in the fuel pump diaphram, <sp> even a small tear or hole will prevent it from proper suction.

Try blowing air back through the fuel line to make sure nothing is in there.

You mentioned water in the tank. If it still has a stock filter, drain it get a new one. The stock Yami one is a filter and a water separator. Very simpe design, gas floats on water, as fuel passes through the filter, water and sediment fall to the bottom. If there was a lot of water in the tank, even if you drain the tank, the filter will hold the water. Now the fuel comming through the filter, even if it has no water comming from the tank, will pick some of that water out of the filter.

Anyway, sounds like the the diaphram to me.

Check that one way valve again, if it works one way, then it is good. probable just a coincidence that that made it work, but if that valve is broken PM me, I think I have a spare.
 

ANT

Just ride
You said the pulse line wasnt shooting out air, pull off your manifold and check the fitting and line to make sure it's not blocked up, that sounds like it could be you problem.

If that all checks out then if you didn't already, buy a carb rebuild kit they're rather inexpensive. When you rebuilt the carb, did you pull out the adjusters specifically the low speed and clean out inside of there? Also when you pull the cover and diaphram off the jet side of the carb, look at the bottom inside of the cover you'll see a little allen screw that in the center or a little off center, take that out and spray through there as well. When I clean out the carb I usually spray the passage with carb clean then use air to clean it out. Take your time with it, you have to thoroughly clean a carb or you'll keep guessing. Good luck with it.
 
Top Bottom