Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

My brother has a 8 year old Agway lawn tractor. It has a B+S 20 hp engine with hydrostatic drive, and I think a 42" mower deck.
He's taken good care of it, and he likes it.
Since I talked him into buying an exmark ZTR last year, he decided to sell the Agway mower, just because he was not using it that much anymore.
Well, the other day for some reason it would not start, so he jumped the battery with his big SUV.

Something happened, because all of a sudden it sounded like the starter was not engaging.  He took it to our local OPE shop.
they told him that he broke a plastic gear inside the starter, and that it probably was not a good idea to try to jump a little lawn tractor with a big SUV.

Anyway, they fixed the starter, and all is now well.   He sold it to our new Pastor for $400.  It stil looked pretty new, and I believe the Pastor is happy.

So I learned it is not good to jump lawn tractor batteries, I guess.......that is what trickle chargers are for.

Is this true?

Frank D.

P.S......mowed the whole yard with the exmark today for the first time this year.......good destressor.

Thanks Guys,
I'm not sure that jumping the battery was the cause........actually, my brother was at his office with it when he needed it jumped, I jumped it with my minivan and it worked fine.
Then he brought it over my house for a good cleaning, when I think he flooded it, tried too many times to start it, then jumped it with his SUV.
It might have just been the time for that plastic gear to go............
Anyway, the Pastor needed to buy something quick.........(his grass was getting high)........my brother had many other offers to buy it, but I told him to sell it to the Pastor. Both of them seem happy with the deal.
I just posted about it because I knew I would get the right answers here..!

Frank D.

Frank

i suspect what happened was a combination of things, with a weak starter gear being the ultimate cause, however due to the increase of amperage from the larger battery,  increased motor torque took its toll. the battery in a mower supports around 10 amp hours while an automotive battery supplies 20 to 30 times that much, (or more in some cases) which allows the motor to develop more power.

a good example of this would be to compare 2 air compressors that provide the same pressure (thinking in terms of pressure being voltage and volume being amps) both compressors supply 120 psi (or 12 volts) but the volume of air provided triples, say from 5 cfm & 15 cfm (or 5 and 15 amps) the higher pressure or amps allows the motor or tool  to work harder without depleating the pressure (or voltage) of the supply.

Heres a good way to see just what an increased amp supply will do using one of the small 12v air compressors available, and a battery charger. hook the compressor to a load, for example a tire that has 30 or 35 psi in it so the compressor has some resistance against it, then connect the compressor to a battery charger, (one with multiple amperage settings) & start running the compressor at the lowest amp setting, 2 amps for example. switch the amp settings to higher settings & listen to the difference in compressor motor speed. the increase in amps actually allows the motor to develop more power, or torque to work more effeciently. then if one is really curious, at the same time take voltage readings at the various amp settings & see how voltage drops as amp demand increases without an increase in supplied amps. there are other factors that will affect this too, such as wire size, & wire length (though length usually isnt a factor in something as small as a lawnmower)

another easy check to see the effect  high amp draw has on voltage is just hook a volt meter (digital works best) to a mower or even an auto battery, note the voltage reading then observe the reading when cranking the starter

any older tractor should be okay with a boost....

however Kohler says do not boost the fuel injected engines that they make. it will fry the computer and apparently its quite pricy.and no warranty on it cause they can tell by looking at it what you did.fries a wire off the outside i guess and a boost is the only thing that will do it.

and as far as vehicles go ,im not real fussy about using them to boost anything,stuff under the hood is just to darn expensive if somthing bad happens.and it seems to when im around 

later chris