# Lawnflite MTD 10hp Problem



## scrappydude (Sep 1, 2006)

Hello, i havent posted in a while but i got a Lawnflite MTD 10hp and we tried everything with ignition 3 switches 3 solinoids, then realized that there is no fuse in it or a fuse knob, would that cause it not to draw power through the soliniod to the starter because it doesnt let any power operate the lights either, if you have any ideas please post, THANK YOU LOTS

KIRK


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## 30yearTech (Sep 14, 2006)

If you can post your tractors model number we might be able to give you a little better insight to your issue. It does sound like you are not getting power to your solenoid, could be a safety interlock switch or some problem with power from your batter. Some MTD units have a circuit breaker instead of a fuse.


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## scrappydude (Sep 1, 2006)

i cant get the number tonight but we tested and there is power coming off the battery but as soon as it gets to the soliniod it stops and then no power goes to the lights or the starter. Ill post the engine model number tomarrow i dont have a lawnmower number 

THANKS KIRK


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## 30yearTech (Sep 14, 2006)

The engine model number won't help that much. Really need the model number from the tractor to see the wiring harness. 

Have you checked to see if you are getting power to the switch?? 

Many MTD units have a circuit breaker under the shift plate, if the circuit breaker is bad then you won't have any battery power to the ignition switch which will not activate the starter solenoid.

Many times the lights are operated off of the AC side of a dual circuit alternator which means they will only operate when the engine is running.


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## scrappydude (Sep 1, 2006)

ok, thanks, there is no circuit braker and we used a tester and couldnt get anypower to the switch, i think it is because there is no fuse, the fuse attatches to the positive wire comming off the battery onto the solinoid but there is no wire or fuse, could that be it, ya, there is no power at the switch and when you turn it on the solinoid doesnt even make a click so there is no power what so ever going into the solinoid, it is wicked, power all threw the cables but stops right at the solinoid, after school i will check for the model # on the mower, thanks

KIRK


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## 30yearTech (Sep 14, 2006)

Well you gotta have power to the switch or it will never activate the starter solenoid. If you look at the back of the switch they usually have letters stamped into or near each terminal. The terminal marked with a "B" should have + power from the battery going to it. There may be a terminal with an "S" on it, this usually goes to the terminal on the side of the starter solenoid, and depending on the setup of your particular rider it may track through a series of safety interlock switches or may connect directly to the solenoid. If it connects directly to the solenoid, then the solenoid will generally have (2) terminals on it and will interlock to ground through the safety switches.


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## scrappydude (Sep 1, 2006)

there is a b on the switch but that just runs the lights, there is no other wires to attatch to the keyswitch but there is a B on it, the red one off of the solinoid is hooked up, if i hook something up to the keyswitch for B then i wont have lights but that doesnt matter, do you know where i can get a cable. Thanks

KIRK


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## 30yearTech (Sep 14, 2006)

scrappydude said:


> there is a b on the switch but that just runs the lights, there is no other wires to attatch to the keyswitch but there is a B on it, the red one off of the solinoid is hooked up, if i hook something up to the keyswitch for B then i wont have lights but that doesnt matter, do you know where i can get a cable. Thanks
> 
> KIRK


What type of cable are you looking for?


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## scrappydude (Sep 1, 2006)

ok, i got the starter and lights to work but where does the alternator wire hook up to, does it charge through the amp meter? now that the wiring works there is no spark????? THAKN YOU SO MUCH

KIRK


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## 30yearTech (Sep 14, 2006)

Alternator wire will usually hook up to the same terminal on the solenoid that the battery cable is attached to.

If you have no spark, you need to disconnect the kill lead wire at the engine to isolate the tractor from the engine. Test for spark with the tractor isolated and if you still have no spark then the problem most likely will be in the ignition system of the engine. If this is the case then the model and type numbers off of the engine will come in handy in troubleshooting.

Let us know what you find....


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## scrappydude (Sep 1, 2006)

ok, when you hook the alternator up to the solinoid it just starts smoking because the alternator gets really hot and thanks, we fixed the spark. Thanks

Kirk


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## 30yearTech (Sep 14, 2006)

scrappydude said:


> ok, when you hook the alternator up to the solinoid it just starts smoking because the alternator gets really hot and thanks, we fixed the spark. Thanks
> 
> Kirk


The most common set up has a diode in the wire coming from the alternator that prevents battery voltage from getting to the alternator winding. The diode is most likely bad and if the alternator got hot it's probably bad as well. 

If it's a dual circuit alternator, you may have connected the wrong output lead from the alternator to the battery. The side with the diode in it can be determined by a small bulge in the lead wire where the diode is installed. You don't have to have the alternator hooked up to use the mower, periodic charging of the battery will take care of it as the battery is only needed to operate the starter, unless you want to run the lights.


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## scrappydude (Sep 1, 2006)

it is a dual circuit alternator, but, i want ot be able to use the lights , they are hooked to the alternator as well, so i fugured that it will run the lights when the engine is running because the lights never hook to the battery, then the power running the lights would go through the key switch and into the batter, the other wire coming off of the alternator is sopposed to hook into a fuse. tahnks

kirk


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## 30yearTech (Sep 14, 2006)

If it's a dual circuit alternator then the lights will work off of the ac side of the alternator when the engine is running. This side of the alternator output will need to be hooked up to the switch that controls the lights, or directly to the lights if you want them on whenever the engine is running. 

The dc side of your alternator is most likely no good if it gets hot when it's hooked up to the battery. You can still use it this way but you will have to disconnect this lead from the battery and periodically recharge the battery with an external charger, otherwise you will need to replace the alternator assembly.


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## scrappydude (Sep 1, 2006)

ok, im going to need to get the alternator to recharge the battery because according to the original owner it drains the battery just trying ot start it so i kinda need it to charge the batter, running lights off the alternator is fine, if i were to replace it, does it have to be a dual circuit or can i replace it with a normal one? thanks

KIRK


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## 30yearTech (Sep 14, 2006)

The dual circuit is the most common type and the least expensive. This type of alternator supplies an unregulated trickle charge. It's purpose is to maintain a fully charged battery in a charged state, but not to recharge a low or dead battery.


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## scrappydude (Sep 1, 2006)

ok so if i use a normal one it will charge the battery but i would have to run the lights of the battery but the alternator would keep it going. The reason why i was wondering this is becuase i have another alternator just a normal one that fits, since im kinda broke right now since i bought the mower and batter. Thank you very much for that and now that is solved i have 1 more question, the spark doesnt wortk, what does the yelow cord do that comes off the switch that attaches to the spark ground, that would be the kill lead, ifi take that off it ashould spark right? THANKS

KIRK


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## 30yearTech (Sep 14, 2006)

That should work, but you won't get much charge replenishment to your battery when your running your lights, so an occasional external charge may be required.

If the problem with the spark is in the tractor wiring, then disconnecting that wire may provide you with spark, but no way to shut down the engine once it's started. You could run a direct wire to the switch to ground out the ignition coil, just be sure you don't hook it up to battery power or it will destroy your ignition coil.


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## scrappydude (Sep 1, 2006)

ok i will try that and see what happens thanks 

KIRK


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## scrappydude (Sep 1, 2006)

ok, i tried that, nothing happened there is no sprak, i have a good coil becuase it came off of a lawnmower that runs, i tried 3 different sparkplugs and they all work, i dont understand why it just stopped, it was working untill we hooked the starter and everything up to the batter, now it stopped, could it be the flywheel? there is a magnet coming apart but idk.

THANKS

KIRK


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## 30yearTech (Sep 14, 2006)

Is the coil that you put on this engine a solid state module (Magnetron)?

Make sure it's installed properly, they can be installed upside down and they won't spark.


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## scrappydude (Sep 1, 2006)

ok, about the alternator, you know how you said power to the key switch goes threw the B on the keyswitch, the wire that gives it power comes of of the amp meter, is it sopposed to, every time you hook power to the alternator it smokes, would it have something to do with the power to the switch thats coming threw the amp meter??
thanks 

KIRK


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## 30yearTech (Sep 14, 2006)

The power going to the switch should come from the battery and not the alternator or amp meter, the power would only be routed from the amp meter if the charging circuit is controlled by the key switch.

Please post the model type and code number off of your engine as well as whatever information you have on your tractor, maybe I can come up with some sort of wiring diagram for you.


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## scrappydude (Sep 1, 2006)

ok, ill have to hook the batt to the switch, but will that stop the alternator from smoking? i could only get the model number off of the engine the one on the tracotr has been painted over, model is 251707 the type is 0147-01 and the code is 74011811 thanks

Kirk


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## 30yearTech (Sep 14, 2006)

Here is a link to a breakdown that might represent your unit. Glenjudy researched this and I have not had time to look at it, but you might and let us know if this resembles your unit. Thanks Glenjudy


http://search.cartserver.com/search...axhits=5&bool=AND&keywords=130-531&go=Find+It


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## 30yearTech (Sep 14, 2006)

scrappydude said:


> i could only get the model number off of the engine the one on the tractor has been painted over


Kirk,
Is your unit a tractor style (engine in front) or a rear engine rider, what size mower deck is on it? How many speeds does the transmission have? the code number on the engine indicates that this mower was manufactured around 1974 does this sound correct?


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## scrappydude (Sep 1, 2006)

it has the engine in the front, no deck, it has a 3 speed trans, it sounds around that year, im only using it for offroad so i didnt buy one with a deck. THANKS kirk


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## scrappydude (Sep 1, 2006)

this isnt similar, to rase my deck it has the arm that is located by the brake wear you lift. Thanks


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## scrappydude (Sep 1, 2006)

ok, i got the wiring firgured out, thanks, i tried 3 coils and 2 flywheels no spark, so im going to try one more coil that i know works and if nothing works than its screwed, THANKS

KIRK


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## scrappydude (Sep 1, 2006)

ok its not the coil. 
thanks 
kirk


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