Volt meter readings
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Volt meter readings
It's a little cold this time of year in the mountains of Colorado but I'm curious... Is it normal for my 89 f250s volt meter to float around 12volts? I usually pull the battery and keep it inside on a stabilizer when it gets into the negatives and even single digits at times. Batteries ain't cheap... but the last few nights I've been running/driving it, it seems to stay around 11 and 12 volts with the heat on full blast and headlights and all. Wondering if that's normal.. seems to stay there maybe go up a little over 12 with lights and heat off.. but before it seemed to be around 14 like smack in the middle of the meter. Wondering if it's battery or alternator issues both of which are new... or if the cold is just messing with it or if it's just fully charged and good. I've been told a couple different things...
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It's a little cold this time of year in the mountains of Colorado but I'm curious... Is it normal for my 89 f250s volt meter to float around 12volts? I usually pull the battery and keep it inside on a stabilizer when it gets into the negatives and even single digits at times. Batteries ain't cheap... but the last few nights I've been running/driving it, it seems to stay around 11 and 12 volts with the heat on full blast and headlights and all. Wondering if that's normal.. seems to stay there maybe go up a little over 12 with lights and heat off.. but before it seemed to be around 14 like smack in the middle of the meter. Wondering if it's battery or alternator issues both of which are new... or if the cold is just messing with it or if it's just fully charged and good. I've been told a couple different things...
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Good to know. It's definitely floated in the middle around 14 or so but lately with it being cold and running the heat it seems to stick around 11 and or 12 especially with the head lights on. Would another engine ground actually balance that? I recently deleted my AC system and put a bypass pulley because the compressor was screaming... not sure if that did anything to cause this.
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Good to know. It's definitely floated in the middle around 14 or so but lately with it being cold and running the heat it seems to stick around 11 and or 12 especially with the head lights on. Would another engine ground actually balance that? I recently deleted my AC system and put a bypass pulley because the compressor was screaming... not sure if that did anything to cause this.
So using another ground is a way to make sure you have enough ground capacity.
If you use your ac compressor bracket, you can easily add a lug'ed wire to the bracket and then run it to the battery negative somehow.
Can you show a picture of your alternator?
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An engine ground added, would only help if your engine is poorly grounded. The alternator grounds through the mounting holes to the bracket, bracket to engine, engine to battery through the primary engine ground. The stock ground is a small diameter , and corrosion will limit it
So using another ground is a way to make sure you have enough ground capacity.
If you use your ac compressor bracket, you can easily add a lug'ed wire to the bracket and then run it to the battery negative somehow.
Can you show a picture of your alternator?
So using another ground is a way to make sure you have enough ground capacity.
If you use your ac compressor bracket, you can easily add a lug'ed wire to the bracket and then run it to the battery negative somehow.
Can you show a picture of your alternator?
the alternator and most of the wiring are pretty fairly new so shouldn't be any corrosion.
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When you can you should upgrade to a Ford 3g alternator and wiring , the 2g is defective design that can result in fires. (At the connector mostly) But i only know its easy for a 4.9l. not sure aabout your engine.
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This is a 7.5L 460 gas and I took it off and got it read at the shop and it was 100% maybe a month or 2 ago... so not sure if that's the issue. As the upgrade may be nice I don't think it's necessary or required...
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Your 7.5 has a manually tensioned belt for the alternator, right?
If you twist the belt on the long side between it and the pulley that drives it, does it stop short of 90 degrees of twist or can you twist it past 90? this would be with your fingers
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Its one of those things where if you just replaced that connector, and just put that alternator in, use it till it dies. If your connector has been messed with more than just installing it on the alternator, I would look for a new one.
Your 7.5 has a manually tensioned belt for the alternator, right?
If you twist the belt on the long side between it and the pulley that drives it, does it stop short of 90 degrees of twist or can you twist it past 90? this would be with your fingers
Your 7.5 has a manually tensioned belt for the alternator, right?
If you twist the belt on the long side between it and the pulley that drives it, does it stop short of 90 degrees of twist or can you twist it past 90? this would be with your fingers
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Then id say youre most likely looking at just high load draw and an alternator that doesnt keep up. You could try downshifting while driving to have more RPM, this may increase your charging. You could also Try LED headlights, and using the next lower setting on the blower fan might help too. On my truck, I found I had a damage to my primary charge wire going to my battery from the alternator, and it was shorting out peridoically on brackets. Making sure your main power cables are good wouldnt hurt.
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With this being an older truck there's only the high setting on the blower for heat or ac if I had ac still. Which I plan to fix. So can't do much there. But I will definitely look into a better alternator and see if that may help. I mean overall the truck still runs fine and all I just noticed since it's gotten 10x colder this past month that the meter seems to float around 11 and 12 instead of the normal 13-14 even while driving. Most of the wiring and all under the hood is pretty new. But I'll scope everything some more tomorrow when it's not 6 degrees out and pitch black dark haha but thank you!
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With this being an older truck there's only the high setting on the blower for heat or ac if I had ac still. Which I plan to fix. So can't do much there. But I will definitely look into a better alternator and see if that may help. I mean overall the truck still runs fine and all I just noticed since it's gotten 10x colder this past month that the meter seems to float around 11 and 12 instead of the normal 13-14 even while driving. Most of the wiring and all under the hood is pretty new. But I'll scope everything some more tomorrow when it's not 6 degrees out and pitch black dark haha but thank you!
And only having the high setting on your fan is definitely a big part of it. I know at idle my blower fan at high will noticeably move the gauge needle, but its not numbered so its only a guess as to how much
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And you charge your battery inside? Hmm that seems weird. If you dont have your headlights or fan on, it will go to the 13-14 right? Theres a chance your cluster isnt reading the voltage properly. Use a voltmeter at your battery when checkiung with the headlights/fan off , to see if its matching the cluster. Do you have a hand held voltmeter?
And only having the high setting on your fan is definitely a big part of it. I know at idle my blower fan at high will noticeably move the gauge needle, but its not numbered so its only a guess as to how much
And only having the high setting on your fan is definitely a big part of it. I know at idle my blower fan at high will noticeably move the gauge needle, but its not numbered so its only a guess as to how much
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I only pull it and bring it inside if i know its going to be negative temps or single digits for days on end and i dont have plans to drive it for a couple days. I try to always at least warm it up and roll around a couple miles every other day or so with the winter coldness... try to keep it active. I have a few voltmeters.. that was going to be my next few steps just to see if the gauge itself is going or what. Everything I've replaced so far within this truck has been original from 88'.. alternator, ac compressor, starter, solinoids and more have all had the 88 or 89 stamp.. so I can imagine it may be time for the little stuff too.. and without the headlights and fan this evening it was floating around 12.5 to 13... but when I warm the truck up I don't even touch the lights and or heat until the engine and everything is toasty. I usually run it for about 20min before I cut any lights or heat on with these cold temps. It's a single cab so it doesn't take long for the heat to warm it. Plus it just runs cold until it's warm anyways and with such a big block it takes some time to get things toasty haha
get your readings, report back
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I just fixed the last one I sent. It was supposed to say with no headlights or fan it wasn't jumping to 13... it still is staying around 12.3 to 12... with fan and headlights it drops a bit under 12 so between 11 and 12. But that just started happening recently before it was stay around 13.. so not sure if they voltmeter is just starting to go on the truck itself or what. I'll do some reads with my hand voltmeter when I get home this evening.