Conquest 8x8 w/ 20hp Kawasaki carb flooding, fuel pump doesn't shut off.

[ARGOJIM]

If you are ruling out fuel a couple of new questions.
Is there oil in the engine? sorry gotta ask.
Does it have good blue spark with the new plugs? If not Are the wires to the ign box still plugged in?
Did the engine kick off a push rod? Kawasaki's are notorious for kicking them off after sitting long periods due to the varnish/carbon build up on the valves.

You should replace the vent line when possible.

[kjac3585]

If you are ruling out fuel a couple of new questions.
Is there oil in the engine? sorry gotta ask.
Does it have good blue spark with the new plugs? If not Are the wires to the ign box still plugged in?
Did the engine kick off a push rod? Kawasaki's are notorious for kicking them off after sitting long periods due to the varnish/carbon build up on the valves.

You should replace the vent line when possible.

Oil is in the engine, I haven't checked the actual spark on the plugs, but they do fire for at least 1-2 seconds and another 2-3 seconds if I play with the throttle after starting it.

I haven't taken the head off so I'm not sure about the push rods. The engine sounds pretty good for the whole 2 seconds it runs, so I'm not sure if that indicates the rods are good or not... I've never had to deal with that problem before.

[ARGOJIM]

If you want to check the push rods, remove the bolts from the valve covers and visually inspect that they're sitting where they belong ( you could crank the engine and watch the valve rockers if wanted), don't forget to put the wire back on the rear valve cover as it is part of the ignition circuit.
The engine will run on one cylinder but lack power and miss, those quiet mufflers can make it hard to notice.

[kjac3585]

If you want to check the push rods, remove the bolts from the valve covers and visually inspect that they're sitting where they belong ( you could crank the engine and watch the valve rockers if wanted), don't forget to put the wire back on the rear valve cover as it is part of the ignition circuit.
The engine will run on one cylinder but lack power and miss, those quiet mufflers can make it hard to notice.

Goes to show what I know about engines... I'll check the rods out after I take apart the carb again, I'm pretty familiar with how the engine sounds when it's working properly and it sounds exactly like it did before I had this issue. Thanks for the tips, I need to get this baby running so I can do a wetlands job I have lined up!

[ARGOJIM]

Just a thought back on fuel, did you pump a good amount into a plastic bottle to check for water?

We also had a problem once which was just reminded to me by a local racer who chased a similar problem for a month, new gas bought at a station in an empty can had diesel fuel mixed in it. You can tell this by a darker tan color to it and weak gas smell.

[kjac3585]

Just a thought back on fuel, did you pump a good amount into a plastic bottle to check for water?

We also had a problem once which was just reminded to me by a local racer who chased a similar problem for a month, new gas bought at a station in an empty can had diesel fuel mixed in it. You can tell this by a darker tan color to it and weak gas smell.

I sucked all of the old gas out of the tank and filled it with new gas with fuel stabilizer. Then I unhooked the fuel line from the carb and ran about a 1/2 gallon through the lines to clear the old stuff out of the system. I'm familiar with diesel and I'm pretty sure there isn't any in the new gas I got. I'm really hoping the carb or those push rods are the problem, otherwise I'll be completely stumped...

[kjac3585]

The problem was the carburetor, one of the jets had some gunk in it and the float needed to be set at the proper level as well. It runs now, but it idles extremely high...basically full throttle when I open the choke valve all the way. We had this problem before, where we had to leave the choke partially engaged at all times, but now it's really bad. I'm thinking it has something to do with the choke valve or throttle valves because they don't close all the way and I'm not sure if they are supposed to or not. I'd say there's about a 1/8" (3mm) gap between the wall and the choke and throttle valves. I tried backing out the idle mixture screw, but it seemed to have no effect. Any ideas?

Here's a pic of the choke valve shut as far as it goes without binding, the throttle valve is similar.

[kjac3585]

All right, in case anyone encounters this problem in the future... I ended up taking off both the throttle valve and the choke valve and sanding them smooth on the edges with 220 grit sandpaper. This alleviated the sticking issues I was having and allowed the valves to close tight enough that you could only stick the thickness of a sheet of paper through the gap. When reinstalling the valves, there is some play between the screws and the screw hole of the valves, so make sure the valve is seated in the closed position where you want it before tightening the screws... this will keep it from getting misaligned. I then adjusted the fuel idle mixture screw and the throttle screw to find the proper idle speed.

[wern]

I have had success before by fitting a low pressure guage onto a T fitting put into the fuel line.You can see the operating pressure and monitor the needle valves ability to hold pressure in the line when the pump is turned off.