Why shoul dMountfild MJ66 need 4 batteries in2 months

Check the "engage" switch. If it is shorted, it will drain the battery.

Make sure wire from battery to starter is connected and there are no problems with wire ( I.e. no missing insulation, cuts and connection to starter is secure.) Also starter may be bad.

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The easiest thing to do.. take it out and bring it to sears or any Auto Parts place. They will match up the size and the location and type of connecting Terminals. Anything the same size will have enough Cold Cranking Amps to turn-over your mower

battery or cable problems
When using the battery , there is insufficient power left to run the ignition system
when pull starting what is in the battery is sufficient to start the engine

I am betting you will not believe this, but, your battery is bad. I just had the same problem last month. Same, same. I have always had good luck with jumper cables, but there was something wrong with the mower battery. When I removed it and replaced with new one, everything is as new.

OF course if you keep turning the engine oner,the starter is going to get hot and start smoking.Its not the battery thats the problem,it sounds like you may have a carb problem or maybe just need a new spark plug

First off a fully charged 12 volt battery should read above 13.6 volts DC, and easiest way to test if the battery or starter are bad is to jump the positive post on the battery directly to the starter side large post of the starter solonoid, if the battery and starter are good the engine will turn over if all it does is arch then the battery or starter are bad use jumpers from a good battery to the starter solonoid of the tractor and see if the starter turns the engine over if so then battery is bad if not the starter is bad. Hope this Helps Don

you have one of three things going on, either your battery is is low, in which caes you shouls have it tested to ensure there is not a dead cell. or you have a bad ground, remove the starter and clean all mating surfaces with a wire brush then reinstall if this doesnt help ensure that your battery is completly charged then try using a jumper wire from the battery to the starter if the starter does engage at this point then the solenoid is bad and needs to be replaced.

it isn't the spark plug if it wont turn over. maybe your battery is dead.

If the screen doesnt even light up then you pretty much stuffed.

If battery isnt charging then the battery's life is gone. you cant really get another battery all you can do is remove it to prevent damage and use it plugged in.

Open the case by unscrewing the four screws (2on bottom and 2 on side)

move the HDD (hard disk) and take out battery and unplug

replace HDD and lid.