My battery barely turns the starter. Could it be a bad a connection?

Help needed once again..
Hey guys, I seem to be having a battery problem. I have a brand new battery on it, and it's still feeling like its dead, it barely turns over. Would it be the connections going to starter? or the ground connection to the frame?

Could be a number of things causing it. Check and clean all the battery conections, check the oil to make sure gas isnt overflowing the carb ( youll smell it and the oil will be thinner) - the combustion chamber could be full of gas causing the slow turn as well. The oil would need changing if it does.

The starter could be wearing out, can try using carb cleaner to clean it first - the battery might not have enough cold cranking amps to turn the motor over/not enough power ( i always get batteries with as much CCA as i can find- more the better)- ign switch or starter solenoid could need replacement.

i recently replaced the startor solienoid. and the battery on charge. and boost still doesnt do it. its my battery in it for my new john deere mower. witch starts it fine.

could have bad valve lash. making too much compression for the starter to spin the motor

Starters go bad all the time - usually the brushes wear out - briggs starters are easy to take apart and put back together- i clean up the area where the brushes ride, scuff the brushes up, clean the whole setup with carb cleaner, slap it all back together and good to go.

I had an issue with a 14.5HP i bot from a tractor junkyard - thing would exactally like yours does- would barely turn over and then snap flywheel keys. They said it was hydro lock - but im thinking they screwed the motor up to begin with and didnt want to admit it.

A larger CCA battery is just more power, a stronger battery , itll last longer and no be as over worked - ive bot 200 CCA batteries n killed em in a month- now i buy 600 and up , my twins need a lot of juice to kick em over.


Pull the spark plug and see if anythings in there ( ie gas or oil) and turn it over w/o the plug in it and see how it works.

i took the plug out and turned it over it turns over good then slower nslower till it stops then i go to crank again nn it barely does. it shouldnt be the batter its a BRAND new one. that i bought this year with my new mower. john deere 18 hp twin. it starts fine.

I would take battery back to the store and see if you can get another one... I bought a cheap one last summer, the guy said it was fully charged but It wouldn't work. Took it back and got a new one.

what i meant to say was. that it came with the mower. its a john deere labeld batter Never had a problem with it. it still Starts my 18 hp twin on my deere perfectly fine

Sounds like the starter is bad then- its drawing too many amps - try cleaning it first before looking for a new one- and those are about $90. Again ive had starters turning perfectly off the tractor , i change it out and the tractor starts fine.


Im just saying from my experience its better to get larger CCA batteries - heck my GT6000 says right on the battery cable use a minimum 700CCA battery - that has a 20HP twin onan. When dealing with electrical and other starting problems, you cant rule anything out. Id also change out the ign switch to see if that isnt an issue either.

thanks for the advice everyone. will be working on it tomorrow for a while. Thanks

Hello guys. i drained all oil. out of the motor. put new stuff in.. took the head off to discover the valve. sleve out once again. so put that back on. and i cleaned the carb out once again. and still wont fire. whats wrong with it. its got good spark

So you got it to turn over good now? I know it may sound dumb, but does it have a brand new spark plug? sometimes they're fussy on plugs.... And if you haven't already, pop the nut off the flywheel to see how the key looks. And make sure the carb is working properly.... If it's an older carb try fiddling with the main mixture.

yes its turning over good now, and yes it has a new plug. well its like 3 weeks old. and what would the flywheel key have to do with it? jusst asking bc i have no idea what that does. flywheel key. also the carb is cleaned and i belive in good mixtures.

The flywheel controls your magneto/spark timing, works basically like the distributor in a car. If the engine runs poorly or knocks, the key can shear and throw your timing way off, but still giving you good spark. I've seen that happen many times to me and other people, it usually stumps people. But it's simple and cheap to fix. It's a B&S right? then you will see right away if the key broken or not, it's square. On a Tecumseh I believe it's a woodruff key you have to pop the flywheel right off.

well come to honestly think of it. the other day i had finished my route of muddin n beaten the hell outta her. and i had her in low idle in the garage. and she runs rough then i heard a bang!. then it omost turned off but stayed on. i dont kno what the bang was. could of been the valve sleeve bc it was out had to go put it back in on the head. and i will check that thanks for the info

Well if you heard a bang like that maybe the sleeve/guide jammed the valve enough to shear that key. You're lucky it didn't bend the valve....If the motor stops turning that quickly it usually breaks your key. So what kind of motor is this exactly ?

12 briggs i/c

Or if the guide popped out- it couldve sheared the key. The reason the flywheel key is there is to save the motor if the pullies underneath or something jams the flywheel - its made of a light grade metal to purposely break. Youll need to remove the flywheel shroud, and the large nut holding the flywheel down- best way to pop it is to use a puller ( screws right into the convienent threaded holes in the flywheel) or ive herd of some people using a large prybar prying up under it, then gently tap the end of the crank a couple times ( w/o damaging the threads)- it should pop ( usually theyll pop off with a large 'bang' ) - nothings broken, its a press tapered fit popping loose. Flywheel keys are at TSC or any advance auto pretty cheeply.

You clean out the remainder of the old one, line up the flywheel notch to the crank notch and slide the key back in, then put the nut back on and crank er down - i use a very light coating of never seize on the tapered end before reassembly - thats just personal preference tho - i did it for years working on my snowmobile drive clutch.

hello everyone.. unfortunatly. it was not the flywheel key. i was hoping it was. but its in perfect condition.. there is a bit of the play on the crank to the piston. so maybe thats fucking it up. anyway im done with screwing around wiht it. its just down right pissin me off. grrr!!!!! possibly soloutions? anyone. ive tryed EVERYTHING!!!.. UGH! im thinking of taking that motor off the frame. PICKING IT UP N THROWING IT! UGH!. im alredy looking into another motor. hopefully i can find a cheap one that works. or a donor tractor with a working motor. and ill figure it out. Any help is appreciated.

Id still pop the flywheel and change the key - its worth it for a couple bucks. Ive had some that looked normal as well, yet they were split in two.

Kind of a longshot here... but what are the chances that the cam drive gear key could shear? I mean if a valve guide popped out and jammed up in the valve, it could happen... I've never heard of that happening but it's a possibility. It's not hard to pull the base off the motor, and it will let you have a peek at the condition of the internals.

Edit: or a broken cam

Edit again lol: or a bent valve!

It would be a shame to give up on the motor if it's totally fixable!

hey guys. i recleaned the carb again. its getting perfect spark. I EVEN used EITHER! to try n start it. IT WILL NOT START! THO EITHER STARTS EVERYTHING!!!!! OMGG! this thing is pissen me off majorly.. -_-...... should i do a complete rebuild? if so. how much would it cost for all the stuff id need. ie gaskets. possibly parts. PS. Also i diconnected the kill wire on magneto so that is not the problem!. i have no idea guys. usualy im good at this kinda stuff. ive fixed many vehicles with problems running. i CANT figure this dam thing out.

Yamaharules163 suggested valve lash. He has a good point- I had that problem with my current 12.5 I/C . Ran fine for the longest time then started to act up, and POOF it just spewed black smoke and died, and refused to start again, altho the entire motor was clean and all parts were mint. I just about lost my sanity trying to figure it out, then I noticed it would spit fuel out the intake when it turned over, and talked to my local small engines guy, he recommended checking the valves, and sure enough the intake valve was so worn that it wouldn't fully close anymore, so a cheap way of fixing this (as I did) is to file down the valve stem on the tappet end, just a few thousandths till you get proper clearance. I forget the specs, something like .008" or .012" My engine has been running at peak performance for probably 3 years now since I did that.

valve lash? could u possibly tell me more of what that does?

It's the clearance between the tappet and valve stem basically. As the valve face and seat wear over time, eventually the valve will not close fully, causing loss in compression. So to check it you have to remove the little crank case breather behind the carb, and use a feeler gauge to check the clearance. If it's tight and has no clearance, as mine did, that means your valve is not closing. Make sure the valves are completely closed when you check this. If you look online or if you have a manual for these engines you will find the proper gap.