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tsh1773
02-08-2008, 02:43 PM
I have a 2004 Scag with a 19HP Kawasaki. First of all, how can I tell if the alternator is working? If it's not where it is found on the engine? The original battery died about a month ago. I assumed it was due to the cold weather. I purchased a new one. It worked fine for about 3 weeks. The it had to jumped off again and again. I took the new battery, had it checked, and it tested good. They replaced it anyway. I haven't tried the new battery yet, as I just got it replaced late last night. Any ideas?

lucforce
02-08-2008, 03:33 PM
You do not have an alternator. You have a stator, a few rotating magnets, and a regulation device.

First, you need to purchase a voltmeter.

mason dude
02-08-2008, 04:08 PM
I had this same problem on a new hustler with a 25kaw, bought new battery, 3 weeks later,I'm jumpin it again. the dealer told me I wasnt running the engine at a high enough rpm to recharge the battery, it was during the drought last year and to save fuel and noise on thin grass I was running about 3/4 throttle, I still pull back on the throttle occasionally but not all day, the test we ran at the dealer was clamp meter to the battery and watch it as the engine is idling and at half and full throttle, even at 80% throttle the juice coming off the engine wasnt enough to recharge the battery, you may want to run this test on your machine, I am unsure of the specs but it is something like it needs 16 volts to recharge a 12 volt battery and at 75-80% throttle was only putting out 10.5 or 11 ,,, this situation will affect your machine more if you have a lot of small lawns,which would mean a lot of starts/discharging.. someone suggested I put a battery maintainer on the mower and plug it in every other night if I just cant stand to run full throttle all the time, I may do just that this year if we have another slow growth period as I hate to run wide open in small areas, sorry this went long

SILVERSTREAK INC
02-08-2008, 04:56 PM
well there should be a fuse for the charging circuit, check that first

coming off the wiring harness on the motor, with it running there should be one wire putting out like 36 volts or is it just 12? ground your voltmeter and test each prong it should be the red one, these motors are externally regulated i believe (meaning your volt regulator which stops charging when the batt is full is somewhere under the control panel or mounted on the chassis the regulator takes the 36 volts and turns it so about 14 for charging, then shuts off power to the batt when it reads the batt is full) if youre getting no power then the stator is bad

but the fuses go often so check that out first

topsites
02-08-2008, 05:07 PM
Yeah we had one like that, after much tribulation that particular mower simply went on the slow trickle charger every single night.

Not the best solution, but something to keep in mind just in case.

SILVERSTREAK INC
02-08-2008, 05:14 PM
the wiring harness adapter going to the mower might be different than my exmark so poke around and see what you can find

looks like it does have a regulator on the side of the motor, it has the two white wires coming to it, i guess you could check both sides there and see if youre getting any power on either side with the motor running. id disconnect the wiring harness from the motor till youre finished the test to make sure youre getting a good reading

if you have power on one side and not the other you can figure it out, it would either be the stator or your regulator, if there is power to both sides coming out then it must be a loose or blown connection somewhere on the mower

if you figure it out to be one of these probs i have that 19hp kawi fc-601v in the pics for sale, the top seal is bad and dosent have bushings so the motor is trash, but if you need a stator or regulator let me know what you have in mind for price ill take 50 bucks for both plus like 5 shipping (the regulator is prolly around 67 new and the stator is prolly something like 70-100?) oh and sometimes magnets like to fall off the flywheel too and will take out the stator, ill throw that in the deal too if thats your prob (you gotta pay shipping though)

Bill Kapaun
02-08-2008, 05:20 PM
Your alternator consists of the stator and rotor. The rotor magnets are under the flywheel and the stator consists of many turns of wire surrounding it.

You most likely have a regulator/rectifier mounted on the engine with 3 wires going to it. 2 wires (probably the same color (yellow?) are from the alternator and the 3rd wire goes to the battery/electrical system.
The 2 wires from the alternator should produce at least 28 volts AC.
The 3rd wire should produce in the range of 14 volts DC.
Disconnect the regulator and check the AC voltage on the appropriate wires with 1 test lead on each wire (AC function on meter) to check the alternator.
Use the DC scale on your meter to check the DC voltage from the 3rd wire to ground to check the regulator if the alternator checks out OK..

tsh1773
02-08-2008, 09:59 PM
I do have a voltmeter. The battery registered 12.53 volts before I installed it. The mower started right up. I immediately connected the volt meter to the batter and the voltage dropped down to 12.42 and gradually started going up. I'll check around some more. Thanks for the input so far.

GravelyNut
02-09-2008, 09:37 AM
Easiest way to figure a charging voltage for a lead acid battery is that the final charge voltage should be 1.125 times the nominal battery voltage. 6 = 6.75, 12 = 13.5, 24 = 27, 32 = 36, 36 = 40.5, 64 = 72

At times the voltage will exceed that when first charging the battery if everything is normal such that 6 = 7, 12 = 14, 24 = 28, 32 = 37.5, 36 = 42, 64 = 75.

corey4671
02-09-2008, 10:01 AM
well there should be a fuse for the charging circuit, check that first

coming off the wiring harness on the motor, with it running there should be one wire putting out like 36 volts or is it just 12? ground your voltmeter and test each prong it should be the red one, these motors are externally regulated i believe (meaning your volt regulator which stops charging when the batt is full is somewhere under the control panel or mounted on the chassis the regulator takes the 36 volts and turns it so about 14 for charging, then shuts off power to the batt when it reads the batt is full) if youre getting no power then the stator is bad

but the fuses go often so check that out first

YES. My Everride did this. It was so bad that I would be mowing and the blades would stop and then the motor sould just die. Check that fuse. A new battery is just a band aid.

Itzkcatz
02-09-2008, 11:06 AM
Check the fuse. I had this happen one time and it took forever to figure it out. It was just a bad fuse.

SILVERSTREAK INC
02-09-2008, 01:17 PM
just cause the voltage on the batt stableizes dosent mean the charger is workin

its like when your cell phone goes dead and shuts off, if you wait 5 minutes and power it back up you can get a few more seconds out of it before it goes dead again.....the mower battery stabelizes itself from the big current draw the starter put on it

youd get a more accurate reading if you engaged the blades (if it has an electric PTO) if the current keeps dropping while you sit there with the blades on then the batt isnt charging i think an electric pto will drain around 7amps and the stator is supposed to put out 13amps or somethin

smokediver
02-10-2008, 03:07 PM
What silver streak said.
The electric blade clutch is almost a dead short. It's actually an electro-magnet so it's a constant heavy load on the battery. That's when you need the extra amps.

tsh1773
02-10-2008, 06:26 PM
Today I think I found the problem. I replaced a fuse that was blown. Now the volt meter reads 14.2 volts without the PTO engaged and 14.5 with it engaged. That's much better than it was. Although it does make me wonder what caused the fuse to blow. The new one seems to be holding up so far. Thanks for all of the input.

SILVERSTREAK INC
02-10-2008, 08:18 PM
awesome! good to hear

i usually blow them when i pressure wash at the end of the year for some reason.

i try to only pressure wash when i gotta cause of how water in spindles isnt good..etc... but sometimes its gotta be done

pw64
10-07-2009, 08:08 PM
I also have a mower that is not recharging the battery...Battery went dead after charging......so to find if it was a bad battery or a charging problem...I did the shade tree mechanic trick and took the negative cable off the battery...and it shut the engine off....which means to me it is a charging problem on the machine...but don't know how to solve the charging problem.