Exmark Lazer HP cutting out!

[oleo]

I have an exmark hp 23hp Kawasaki that is sputtering and shutting off after it gets warmed up for about ten minutes. It really likes to shut off when I have the pto going. I have spent $94 on coils put and with new coils in it and new spark plugs the POS still does it. The impulse fuel pump seems fine b/c I took off the line to the carb and turned the engine over it is impulsing gas. I know its not the safety switches. When it starts to sputter I can pull the choke and it is obvious it needs gas. The fuel filter is fine also, gas flows through it real well. I also drained the old gas from the pan. It is new gas in the tanks, the lil bit I had in the tank had stabil in it. Any suggestions would be appreciated! I called Kawasaki and they werent helpful one bit, very rude and arrogant saying it cant be from the engine. Check with exmark. This is so frustrating having a machine that runs fine for 10-15 minutes but then once warmed up, it just sputters and dies.

[Talon1189]

It sounds like you did everything except make a carb. adjustment. Sounds like you are running too lean to me.

[rick2752]

Dont know about the Kaws but the Kohler has an electric selenoid on the carb. I had a similar issue and the problem was a loose wire on the back of the ignition key. Pull the panel and look behind there. Mine were loose and getting hot and killing the mower.

[oleo]

Thanks for the comments guys. I will try to make a carb adjustment. If it was the solenoid which isnt cheap $95, would the engine even run? It starts up fine but once it gets warmed up that is when it starts cutting out and sputtering. This is when I will pull the choke and it comes back. It only sputters with quick movements going forward and backwards and when the pto is on. Seems like it really fails when full power is needed.

[rick2752]

I know it sounds stupid, but did you check the back of the key switch? Mine was doing Exact same thing. I thought the selenoid was maybe bad, but it is hooked to the key switch which makes it kick in and out.

[Partsangel]

Quote(10-15 minutes but then once warmed up, it just sputters and dies.)

Sounds like it might be a valve adjustment issue to me or a vapor lock in the fuel system? check and make sure your gas cap is venting properly and its always good to check your valve lash/clearance on a regular basis.

Thats my two nuts and bolts of info.

Mike AKA Partsangel

[oleo]

I pulled off the key switch, cleaned it with my air hose and made sure the connections were clean and tight. Ran it for about 10 minutes and the POS does the same thing, sputters and dies. My dealer thinks it needs a new carb possibly. I really dont think it does because it would always run terrible if the carb was bad. I am going to tear apart the carb and see if there is some dirt or rust in it from the moisture and dust?

[oleo]

Mike,

What is the valve lash/clearance?

[Partsangel]

.004 Intake and Exhaust
Im not sure of what model you have exactly but you might have to let your piston drop 1/4 inch past TDC to bypass the compression release system.

Mike AKA Partsangel

[rick2752]

Are you getting juice to the carb selenoid, try a test light with key on and off.

[oleo]

I took it in to my dealer and they took off the carb and cleaned it. They charged me over $150 and said they fixed it. I took it out to an account and it died within 20 minutes. What a good deal that was.
I am pretty sure if it was the solenoid, the thing wouldnt even start. I bought a new impulse pump and it didnt help. It still starves for gas.
Hey parts angel, how do I do a valve and carb adjustment? Does anyone know much about the carb on these Kawasaki's. Are they known to have problems.

Glad to see exmark is helping me with this!

[brucec32]

I posted this before but I had similar symptoms with a Kawi 23hp and knowing that my Exmark dealer had had problems with diagnosing problems before, I stopped by my toro dealer and spoke with the mechanic. He instantly told me "check your fuel filter and lines". I went home, did that, and it has run fine ever since. Clogged filter that didn't look dirty.

[rick2752]

Any luck yet? Have you replaced the fuel lines? Is it sucking them closed in a bend somewhere?

[oleo]

Well I replaced the fuel lines to the carb to see if gas was being pumped and it is. I now have taken it to another dealer to look at it. Took it in on Monday and hoping to have it back by Friday. Talk about having some pissed off customers that are expecting their lawn dethatched! I could rent a mower but no one around has a jrco dethatcher and bagger mounted on their rentals. Hope they can figure something out with the POS and I can use it this weekend!

[rick2752]

any update?

[11baron]

Ok, for what it is worth here are my two cents. In situations like this, it is generally something very simple. I believe your problem is electrical in nature. The reason I believe this is because the machine runs fine until it is warm. A cold electrical connection can be tight and work well, even though it is faulty, or loose or what have you. Once this faulty connection warms up, it seperates, causing problems you don't have in a cold engine. Since it is a carburated model and you have replaced the fuel filters and line, I would check the ignition module or modules. There should be some type of sensor on the flywheel that will cause the coil to spark. I wouldn't think you have a distributor, if so check that also. At any rate, these modules need a specific gap to the flywheel, look in your repair manual and see what you can find. Please keep us all updated. I realize it appears to be starved for fuel, but really, at this point it could be anything. Since it runs fine cold, and does not run correctly when warmed up, I don't think it is fuel related. Follow the leads from your coil and see where it goes. I wish you luck, keep us posted.

Regards,

Bryan

[DEEJ]

oleo,

I agree that this will end up being something simple, but what. Based on the evidence, and what has been done already, I would look in the following areas:

1. Coils have been replaced - is there an ignition module? If so this could be faulty. You are describing the conditions perfectly. Runs fine cold, does not run hot. Classic failure in a car. Classic failure in my Kohler 18hp!!! The only evidence that goes against this is the recovery by pulling the choke out.

2. Recovery by pulling the choke out suggests it is fuel starved. This could be from a plugged carb. That has been serviced, so things should be ok there.

3. The next spot to look is the fuel filter. Dirt will fall away from the filtering media and allow just enough gas to flow through that the engine appears to run fine cold. When the engine runs for a few minutes, the dirt slowly clogs the remaining holes in the fuel filter again, and the engine loses power - most evident under load. When the engine is shutoff, the cycle starts over again. The symptoms generally get worse over time. This is a common problem with cars when the fuel filter has not been replaced for a while, or the fuel tank has been replaced and dirt has been introduced into the system. I see no mention of replacing the fuel filter so far. Just do it. Forget looking to see if it looks dirty, just replace it.

4. Are there any screens, secondary filters, or fuel pickup screens. These could be anywhere in the system from the bottom of the fuel tank to the fuel pump to the carb inlet. Anything that will restrict the gas flow will provide the symptoms you are describing. If there is dirt in the fuel tank (and it doesn't take much) the fuel pickup screen will clog the same as I described for the fuel filter above. In the grass cutting business, dirt in the fuel tank is not uncommon!!! When you shut the engine off, the dirt will fall away from the screen because the suction is gone. When you restart, it takes a few minutes for the screen to suck the the local dirt back in. Look for fine fibre-like dirt in the screens.

5. Have any of the fuel lines deteriorated inside? This sometimes happens as the rubber hose ages. It looks fine outside, but pieces are falling off the inside and plugging the line itself, or filters, or screens, or the inlet to the carb. This is less likely, but I have seen it. Careful inspection of every line will usually find the problem. If you even suspect it, replace every line.

Let us know what you find.

deej

[rick2752]

I agree baron that it is electrical. Reason being I had same problem, but mine was not getting juice to the selenoid on the carb that opens to give it fuel. I was thinking fuel problem all the way and just happened to check the selenoid with key on at the carb and there was no juice. Good Luck and let us know.

[slplow]

What is the out come ? My 23 kawi is stalling , my dealer thinks it's dad gas.