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LX 255 stalling

#1

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Bob1944

Lx 255 starts fine but then stalls after about 30 minutes. I replaced the spark plug, air filter, and fuel filter but did not help. It has a kohler cv15 engine. Only other thing I noticed was that the battery light stays on which that never did before. Do not know if battery would cause this or not, but I checked the voltage when cranking and it did not drop down much at all. I downloaded the cv15 manual, but that was way over my head. Any suggestions would be greatly appreciated.

Forgot to mention that problem started after we moved, and I had to drain as much gasoline as possible out of the tank before loading it on the van. Could that cause this?


#2

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bertsmobile1

check the battery voltage engine off and battery voltage engine running
Let us know what you find.

Little steps. one at a time.


#3

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Bob1944

Thanks for the reply, but I must have something wrong as I did not get an email saying there was a reply?

Anyway I took a chance and ordered a coil which should be here today. Mower is currently apart waiting for the part so can't test voltages now, but will post back after installing either way.

Thanks!


#4

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Bob1944

Gmail got me by classifying the email as Spam. My Bad!

Well the coil was not the problem. Same problem: stalled after about 30 minutes of cutting. Orange battery light still on whole time.

Voltage off: 12.54
Voltage running: 13.78

Since I ran this time with the hood off, I could see that the fuel filter looked like not much gasoline in it. Is that normal? What should I try next?

TIA,
Bob L.


#5

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bertsmobile1

Next step is to run the mower till it stalls then spray some starter fluid down the carb.
Fire right up = fuel delivery problem
Next loosen the fuel cap
Fires right up = tank vent blocked
Next step pull the fuel line off the carb & crank the engine a few times then pull the fuel filter off and do the same.
There should be a little difference between the two but not much.
Some like to crank into a cup for a fixed time or measure the time for a fixed volume.
Big difference = blocked fuel filter
Assuming they are the same blow backwards into the fuel tank ( cap loose or removed ) from the fuel ile before the pump as the pump has a one way valve in it.
Fires right up = blockage in fuel line of debris in fuel tank blocking outlet.

All of these make no difference then you are left with the fuel solenoid or a valve problem


#6

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Bob1944

Actually when it stalls, I can start it back up without doing anything and it will then run for a while again. Where is the fuel solenoid and what does it do? Any thoughts on the battery light staying on?


#7

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bertsmobile1

Well that makes a big difference
by stall do you mean slows down then stops or just stops like you turned it off or stutters a little like it is running out of fuel.

Sounds electrical.

Fuel solenoid is the thing hanging off the carb with 1 or 2 wires.
It jambs a ram into the end of the main jet to stop fuel flowing through the carb when you shut off the engine.
If the plug is loose or the wires are loose or shorting out then it will close & the engine stops dead .

Charging lamp is controlled by a relay or a bridge switch in the rectifier, I do not have the service manual for your mower


#8

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Bob1944

It slows down and then stops. I can tell it is going to happen. If I choke it will do better though eventually still dies.

I put on a new fuel solenoid but problem remains. Tried pulling fuel line from carb etc. but gas flow seemed strong and the same wherever I tested. I also read another thread somewhere saying to clean the magnet on the flywheel, so also did that!

Really frustrating, in that you would think the same behavior over and over again would point to the problem!

I have gotten 17 years out of this puppy so maybe it's time to move on?


#9

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bertsmobile1

Little by little you are spoon feeding us information that is vital to proper diagnosis.
If choking the engine helps a little then it is definately a fuel problem.
Can be as simple as the fuel tank vent being blocked or some floating debris blocking the fuel outlet or a duff fuel pump or a cracked impulse line.

After it stalls out pull off the fuel cap.
Runs OK for another 30 minutes = fuel cap vent blocked

Makes no difference , pull fuel line off at the tank side of the pump , remove the fuel cap & blow backwards down the fuel line.
Runs fine for another 30 minutes = floating debris in fuel tank.


#10

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Bob1944

My apologies for spoon feeding, but I am just reporting what I am finding when I find it.

I know this was the wrong way to test, but I had convinced myself the problem was the fuel cap, and I wanted to not get stranded. So I ran today holding the cap just over the opening so it was open but fuel wouldn't slosh out. I did that expecting it would never fail and I could therefore get my drain field cut with no problem. However after about 30 minutes it failed while open. Since it was open I immediately screwed it back on and as I did so it stopped failing and returned to running ok. Did not make sense to me so I kept running with the cap on and it failed agin. So this time I pulled the line at the fuel pump and blew back into the tank. Started right up and kept running with the fuel cap on tight.

So sounds like debris in the tank or maybe the fuel line? What I don't understand is why it always takes about the same time to occur. Why is that? Also what is an impulse line?

I really appreciate your staying with me on this as this is all new to me!


#11

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bertsmobile1

The impulse line is a tube that connects the crankcase to the fuel pump.
as the piston rises & falls you get pressure variations so the line blows then sucks.
The blow/suck/blow/suck is used to power the diaphragm to pump the fuel.

As for why the time, a mystery of nature.
The crud is floating around in the tank and gets sucked into the outlet tube much like hair getting sucked down the bath drain.
Bad news is if it is floating debris, it will be a tank out, and multiple washes,
Buy a length of fuel line and replace the lot from tank to carb while it is out because crud ca also get stuck on the inner wall of the tube.


#12

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Bob1944

I found a link about draining the tank, and it calls for removing the fender/deck. I started to do that but got nervous when I saw that the forward pedal and reverse Pedal appear to lift right off with the deck. Before going any further I am wondering how can that be, or more to the point, how does it go back together again? Do the pedal mechanisms just sit down into something? :confused2:


#13

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bertsmobile1

One bolt each and the pedals come off.
From memory they are different sized bolts and have different ends but this is exactly the reason why digital cameras were invented and why they put one in your phone.
Bet you thought it was to take funny pictures of your cat didn't you :laughing:
If yours is the one piece floor & fender then you will find a second pair of hands very helpful.


#14

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Bob1944

Thanks, got pedals off, deck off and tank out! Emptied tank into bucket and saw lots of small crud plus a maple leaf so I think you nailed it!

Washed out tank and new fuel line arrives Sunday. Hopefully that will do it.

Thanks again for all of your help!


#15

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bertsmobile1

Confession time.
The land lord got a 2000 series Cub and it is a brilliant mower, but used to stop after a period from 1/2 to 1 hour.
We faffed around with it for over 2 years, took the side covers off so the engine could get more air, changed magnetos , fuel pump, fuel filters , fuel lines, carb, fuel cap relays .
After a while, they just lived with it and when it stopped they took a break .
There were a lot of 2000 series Cubs for sale with a "hot running problem "
By chance the fuel line was pulled off and nothing came out so No 1 son blew backwards up the line and we all got a petrol shower.
Penny dropped
Off came the tank and it was chokers full of grass clippings that sort of floated around inside the tank.
After a clean up ran for hours till the PTO clutch overheated so he bought 2 more " problem" mowers.
In the mean time I bought the repair run and seeing the price used 2000's in good nick went for bought 15 in the first year , cleaned out the tanks and I now have 15 very happy customers with good used Cubs

Get some good light and have a close look at the inside of the outlet spiggot.
Several of these Cubs had a casting flash almost blocking off the outlet before you even start with debris.


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