Craftsman lawn tractor model # 502.251220

This is a continuation of a thread I started back in 05/2008 I think. Yes it has taken me this long to get to it. Not high on the priority list as I have a push mower.

This should take you straight to the previous info. http://www.ytmag.com/cgi-bin/viewit.cgi?bd=gardent&th=85260

I changed the PTO and clutch switch (parts 7 & 10 from the parts manual). The parts come from Briggs/Stratton. They apparently sent me the wrong seat switch though. The nut is welded to the seat plate so it will take only one type of thread and the thread is different between the new and old. Suppose I could cut the nut off and use any appropriately sized nut?

Results were no different with the PTO and clutch switch changed. I also put the battery on a charger just to be sure. Still dies when you engage the blades. I will clarify a little too. I can move with the blades engaged for a short while like 20 yards or less and then it dies. This leaves seat switch, ignition switch, wiring and/or carbs.

This does make me wonder about the battery. What if the battery is not rated for the type of mower? Could it have enough juice for it to start but not enough to keep it going?

The one that is in there now is Everstart part # U1, says cc at 32 degress is 175 and cca is 140.

From the sears parts site it gave me a battery part # 27195. I went back to the main sears site and it came up with a U1 Die Hard battery which is 340cca. Even though it references the same part #, the difference is the part list says it is a U1-L5 battery and the Die Hard is a U1R battery. Not sure if any of that makes a differece or not.

I just looked at the manual and I did find this: "Note: If the engine stops when you engage the blade(s), the seat switch is not activated, Make sure you sit in the middle of the seat. Also, make sure the wire is connected to the seat switch." My only thought on this is if the seat switch wasn"t activated, then I wouldn"t be able to start it at all, which I can.

Thought on the carbs too, if the mower starts and can go anywhere on the mower without it dying when the blades are not engaged, why would it be a carb issue when I engage the blades?

Lsst thing I can think of right now is I can"t seem to start it in the choke position. Seems to only start in the fast position.

Again thanks for any help/thoughts/suggestions.

Jerry

you might try wtaching batt voltage when useing the machine to see if its low.

Try leaving seat sw disconnected,sw only affects eng ign,if tractor still dies,locate & disconnect ign kill lead at eng,this takes out all safety sw's & ign sw,if eng still dies,then problem in fuel system,if eng doesn't die with kill lead disconnected,then problem in seat sw or ign sw,seat sw is start of ign kill circuit,if seat sw loose due to mounting,with deck vibration & possibly you moving on seat,plunger not being depressed enough & contacts close in sw,killing ign.

U1 designates the case dimensions etc of the battery,U1s come in different outputs...340 Amps is a good sized L&G battery..The transparent cased cycle types are too small,even the larger black ones are only 250-300A.Sounds like you need the biggie,that looks like a minature car battery.....(The 502 prefix would make it Murray built,now servived somewhat by Briggs.

I do not know of any Briggs engine that needs the battery for the ignition. I do not know if the engine has an anti-dieseling solenoid on the bottom of the carb. If the mower clutch is pulling some much current or the battery is in very poor condition the voltage of the battery could drop so low that the anti-dieseling solenoid could be closing. I more likely think you have a safety circuit problem.

Kent

I have some good news. I got it running. Was able to mow most of the back yard. Died a couple times and had lots of backfire too. But there for a goodwhile it stayed running and mowed most of the back yard with it. I'm going to pull the manual and see how the carb should be set to make sure the mixture is right. Especially considering I still cannot get it to start in the choke position, I am sure something needs adjusted. Seems to only start in Fast position. Not sure if there is an engine and/or carb rebuild kit either.

I did disconnect the seat switch and it did die on me again. I didn't have the info. with me so I forgot to find the kill lead. I did notice too that the gas cap is cracked and part of the engine was wet, guessing gas leaking somewhere? I did tighten the gas cap down a bit and after that it seems to run so not sure if the gas cap has anything to do w/ it either. Got a new battery too. The previous one still had the receipt attached and it was bought 05/2006.

Pulled it up front to fill the tires w/ air and one of the front tires didn't have the schrader valve sticking out. Found out it was inside the tire. Man those things are hard to remove. Have to replace an innertube too. Might take it to my local motorcycle/dirt bike shop to see if they will put the tire back on once I get the new innertube.

Your battery is too small for an electric clutch mower. should be 300 cranking amps or more.

If your mower has the fuel solenoid under the carburetor, when the battery voltage falls enough it will close, stopping the engine.

The only way to tell what your battery and alternator are doing is to put a volt meter on it and see. should be 12.6. And after you start it it should go over 13v and stay there, even when the electric clutch is engaged.

in case anyone missed it. showed up in the middle instead of the end for some reason.

I have some good news. I got it running. Was able to mow most of the back yard. Died a couple times and had lots of backfire too. But there for a goodwhile it stayed running and mowed most of the back yard with it. I'm going to pull the manual and see how the carb should be set to make sure the mixture is right. Especially considering I still cannot get it to start in the choke position, I am sure something needs adjusted. Seems to only start in Fast position. Not sure if there is an engine and/or carb rebuild kit either.
I did disconnect the seat switch and it did die on me again. I didn't have the info. with me so I forgot to find the kill lead. I did notice too that the gas cap is cracked and part of the engine was wet, guessing gas leaking somewhere? I did tighten the gas cap down a bit and after that it seems to run so not sure if the gas cap has anything to do w/ it either. Got a new battery too. The previous one still had the receipt attached and it was bought 05/2006.

Pulled it up front to fill the tires w/ air and one of the front tires didn't have the schrader valve sticking out. Found out it was inside the tire. Man those things are hard to remove. Have to replace an innertube too. Might take it to my local motorcycle/dirt bike shop to see if they will put the tire back on once I get the new innertube.

ok. one more time. Reposting in case anyone missed it. Showed up in the middle and the top for some reason.

I have some good news. I got it running. Was able to mow most of the back yard. Died a couple times and had lots of backfire too. But there for a goodwhile it stayed running and mowed most of the back yard with it. I'm going to pull the manual and see how the carb should be set to make sure the mixture is right. Especially considering I still cannot get it to start in the choke position, I am sure something needs adjusted. Seems to only start in Fast position. Not sure if there is an engine and/or carb rebuild kit either.
I did disconnect the seat switch and it did die on me again. I didn't have the info. with me so I forgot to find the kill lead. I did notice too that the gas cap is cracked and part of the engine was wet, guessing gas leaking somewhere? I did tighten the gas cap down a bit and after that it seems to run so not sure if the gas cap has anything to do w/ it either. Got a new battery too. The previous one still had the receipt attached and it was bought 05/2006.

Pulled it up front to fill the tires w/ air and one of the front tires didn't have the schrader valve sticking out. Found out it was inside the tire. Man those things are hard to remove. Have to replace an innertube too. Might take it to my local motorcycle/dirt bike shop to see if they will put the tire back on once I get the new innertube.

(quoted from post at 13:36:06 08/29/09) Try leaving seat sw disconnected,sw only affects eng ign,if tractor still dies,locate & disconnect ign kill lead at eng,this takes out all safety sw's & ign sw,if eng still dies,then problem in fuel system,if eng doesn't die with kill lead disconnected,then problem in seat sw or ign sw,seat sw is start of ign kill circuit,if seat sw loose due to mounting,with deck vibration & possibly you moving on seat,plunger not being depressed enough & contacts close in sw,killing ign.

Click to expand...

I have the opposite issue with this machine. the switch itself is good but when it is in the norman position ie. unoccupied seat the engine won't stopwhat is on the other end of the socket that it plugs into? Does it connect to the ignition switch?.
Much appreciate help if possible

Sounds like a charging problem.
The only power used by the battery when the engine is running is the fuel solenoid valve on the carb if equipped. If the engine does not have a fuel solenoid valve. The engine will run without a battery even connected to it. A good fully charged battery will start the engine many times before it goes dead.

The PTO will draw all of the amps from the battery until the engine gets back up to operating speed if it is charging good. It will shut down within a few seconds if it is not charging good.

You should have something between 13.6 and 14.2 at the battery when the engine is running. If not. Check the charging system.