Testing alternator???

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DIXIEDOG

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Anybody know of an easy way to test the alternator on a RTV 500? I've gone to start my 500 a few times now and had to get a battery jump box to get it to kick over. I know the winch draws alot of power and I could just be running it down but I want to be certain my alternator is OK while it's still under warranty.


If the alternator is OK I'll just go find an AGM deep cycle battery that fits and be done with it.
 
start up the rtv then disconnect the battery then put a small taillight bulb to the battery cables if it comes on you have juice comin from your alternator .or you can use a voltage meter buy unhooking the battery after starting and touching the wires it should show some voltage.
 
It's pushing 14.7 volts so it's probably OK. I hooked the battery charger up to recharge the battery and it's reading 100% even though it only ran for about 5 minutes after it wouldn't start at all. Me thinks the battery is toast. :confused2:
 
Sounds like either the battery's gone bad, or you have a drain some-place in they system while it's shut down.
You don't need to disconnect the the battery to check it....check the voltage with the engine off, (Should be a little over 12) then again with it running..I think yer right with a little over 14.
 
Thats the right way to check the alt. Anytime you disconnect the bat with the engine running, you make a spark or spike, which can blow some of the electronic parts!
 
The Red's have it right. With Engine off, check battery with a voltmeter, it should be around 12v. Then check it with engine running, it should be in 13v-14v range.

Sometimes (especially on diesels) the idle is so low that you may need to rev the engine a little to get the 14v out of it.

To test for an electrical drain - with key off, disconnect ground from battery. Then touch ground cable back onto the negative post, if there is ANY spark, then there is something draining the battery.(this is eaiser to check in low light conditions)

Your thoughts on the battery sound right. Most parts stores will load test a battery for you. Between vehicles, mowers, & equipment, I purched a load tester & it has come in handy many times.

Hope this helps, Rich
 

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Can't imagine the battery being bad so quickly. I plowed for several years with a Honda trx 450 with winch/plow and never had a problem and it was only a 12amp/hr battery.
I agree, 12v with everything shut down and 13.5-14.5v with engine running when checked across the batteries negative and positive terminals, usually means a good charging system.
Good point, check for a drain when everything is shut off. If you wired your winch in so it works without the key, you may have a little draw that is killing your battery in this cold weather.
And if all else fails, have your auto store load test the battery. Done in the above order should narrow down the search; 1- battery voltage, 2- drain test, 3- load test.
 
I have worked in a few shops and what i have found out that the first thing you check is not only how tight the belt is but make sure the belt is not glazed over so that it slips when the RPMes increases, it can be tight but slick. Then you need to check for volts but you also need the alt to put out amps, i have seen a alt put out volts but very low amps. You can also put a test light inline after you unhook the neg cable,if it is neg ground, to see if you have a draw when the key is off, if the light is lit you got a draw, better is a volt/amp meter with anything above .5 amp is too much.
 
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