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Voltage Spike?

Voltage Spike?
JSnow

JSnow

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Patuxent Hills Farm, MD
Got a weird one, this morning I noticed my blower motor spooling up then slowing down, looked over at my volt gauge and she was pegging out and dropping back to normal levels. my lights were also following suit, so it isn't easy as my guage is fubar'd

I've never seen anything like it, is my alt broken? usually it works the other way around for me :D
 
JSnow said:
Got a weird one, this morning I noticed my blower motor spooling up then slowing down, looked over at my volt gauge and she was pegging out and dropping back to normal levels. my lights were also following suit, so it isn't easy as my guage is fubar'd

I've never seen anything like it, is my alt broken? usually it works the other way around for me :D
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I'm definitely not a electronics expert, but I'd have to say I agree. Sounds like the internal voltage regulator is having some issues.
 
Your voltage regulator or the alternator, one of the two are going bad.

Any one of the chain parts stores (autozone, advance auto, etc) will test them for you for free.
 
If you're not trying to power a winch or run a dozen offroad lights, honestly I don't see any reason for anything other than OEM replacement. But that's just my 2¢.
 
elwood blues said:
If you're not trying to power a winch or run a dozen offroad lights, honestly I don't see any reason for anything other than OEM replacement. But that's just my 2¢.
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X2 on that. Elwoods right, if your no using a lot of amps(i.e. Winch, Big stereo, multiple off road lights) there's no point in a big alternator. The use more HP, produce more heat.;)
 
JSnow said:
Right on, I would like a winch and some offroad lights eventually. guess I can hold off for now
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Advice on Winch, Hi Amp Alternator, Off Road lights.
Or all of the above
 
JSnow said:
All of the Above!
So my wife can surely kill me when the boxes show up :D
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Rodger that!;) I always loved the "Warn 8274" as winches go it's always been near the top of the heap. Fastest unloaded line speed, most line capacity and I think "Moses" used one on the "Ark". On Alternators "Mean Green" is a good brand. Off Road lights are in flux right now. For the money the old fashion Halogen are best now. HID have better performance, but are very pricey. Pretty much the same for LED right now, but with less range than HID. LED's are coming on strong, both HID & LED are starting to come down in price.
 
JSnow said:
thanks, maybe I'll just go ahead and just upgrade the alt rather now rather than replace it again later.
I'll have to see if my buddy can get me a discount on one of the mean greens.
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Good Luck!;)
 
Did you ever go and have the alternator checked??
I agree with Elwood and Longhorn, I think you need an alternator but its all part of their free service and proves beyond any doubt. I always have alternators and starters checked before I replace them. It can save a lot of embarrassment later.:o
 
I went 130A single wire from DB Electrical. Good folks! Just watch your buddies eyes when you give them a jump after they sucked their battery dry winching for 15 feet. Besides I run a Milemarker hydro. Winches for hours pulling dead electro winch guys out.
 
thought I'd give an update...My buddy was going to rebuild the alternator for me he told me to pull it and get it tested. was going to do it that night but when I left work everything was reading fine so I just let it go...

fast forward to today, stop to fill up for gas this morning hop back in, turn the key and nothing. no power at all...traced it to the connection on the alt, it's completely corroded. cleaned it up pluged it back in and she fired. now it's pegged back at 16+ volts. Sweet!!!!

going to rerun the wires this weekend just to be sure and get it tested, I need to replace my water pump\ps belt anyways so I'll just take it with me when I go to the store.
 
JSnow said:
thought I'd give an update...My buddy was going to rebuild the alternator for me he told me to pull it and get it tested. was going to do it that night but when I left work everything was reading fine so I just let it go...

fast forward to today, stop to fill up for gas this morning hop back in, turn the key and nothing. no power at all...traced it to the connection on the alt, it's completely corroded. cleaned it up pluged it back in and she fired. now it's pegged back at 16+ volts. Sweet!!!!

going to rerun the wires this weekend just to be sure and get it tested, I need to replace my water pump\ps belt anyways so I'll just take it with me when I go to the store.[/QUOTE

well, you had your chance to upgrade to an expensive after market alt. and you blew it!! Don't blame us!!:laugh:
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When I was "sweet sixteen".:laugh: I had a rig with a electrical problem. I replaced the alt, Starter, & battery, still had a intermittent starting problem. Come to find out the Positive battery cable that looked perfect on the out side, was totally corroded under the insulation. Go figure.:rolleyes:
 
Don’t let the 16 volts fool you, factory gauges (assuming you have one) are off by as much as a full volt, usually the read less than what is in the system. Most batteries will boil or mist at 17 volts so you really want to check this before you destroy a battery.

The factory regulator is set at 14.5 volts, it is possible that you have a regulator with a higher set point, however the only way to tell is the disassemble the alternator.

So you really need a good digital gauge and you need to do a voltage drop test, and be sure to check your grounds, start at the battery and move back on both the ground and positive.

If you would like to read more on grounds and voltage drops you can check the link. Grounds! | The National Voltage Star

be sure to do a voltage drop test on your electrical items such as blower motor and wiper, make sure you have the correct fuses in the correct locations, the problem we find is people put in I higher fuse when they blow one. If you blow a fuse it will tell you which circuit has the problem.

You are on the correct path this is usually loose connections but if you have ungraded the alternator be sure to run a larger cable from the alternator to the battery and replace the fuseable link with a fuse. The factory charge wire is only good for about 70 amps.

Hope that helps.
 
If the battery's an old battery it may be the battery spiking too. I had this happen on my 04 Grand.

I'd be driving down the road and the gauges would die then come back on.The battery ended up being bad.
 
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