Tonight, I was driving in the dark (with the headlights on) and the charge light started flickering slightly, more at lower revs and less at higher (as one would expect) but even @ 3000 the light was dimly lit. I've driven her enough at night to know that this is new.
Car is starting and running like a champ. I inspected the belt and everything looks okay to my untrained ideas.
Alternator starting to go? Any thoughts?
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maybe a loose ground somewhere. get tightening.
How many miles on the generator? Perhaps wiring or brushes worn down.
From your profile pictures looks like you indeed do have an alternator with an internal regulator. Check battery to see if it needs water. The check to ensure drive belt is not crazed and slipping then head to a local auto parts chain that can quickly pinpoint if alternator, regulator or battery --- most do for free. Easy to replace regulator and even diodes if need. Alternators should charge at even low RPMs --- unlike older generators.
Tom,
If you have, for example, a 70 amp alternator, that 70 A rating will be at about 4000 rpm, not idle. Depending on the electrical load, your alternator may not be able to keep up with amperage draw of your system, depending on fans, lights, stereo, etc. An easy way to check is to put your volt/ohm meter on your battery posts. Check battery voltage prior to starting. Then start the car, and see if the voltage increases. If voltage goes up, your alternator is putting out. Voltage should increase to 13.5 or more V. Then turn on accessories. Check V again. If it decreases, increase engine rpm. If voltage stops increasing, you may need a larger alternator. High output alternators put out efficiently at idle. Depending on the ratio of alternator pulley diameter to crank pulley diameter, 2000 engine rpm may give you 4000 alternator rpm.
The plan of the system check above is for the user to determine system needs and abilities prior to pulling the alternator or going to the auto electric shop. A few minutes with a decent multi-tester or volt ohm meter can tell you much of what you need to know about your system's load and charging capabilities. After market lights, stereos, fans, etc. all add to the amperage load, and a normal alternator may not put out enough amps at idle. Be aware that merely turning your alternator faster by reducing pulley size may cause overheating of the alternator.
Should have done a search first https://www.speedsterowners.com...ternator-idiot-light
You can do same check with a volt meter and someone to rev engine - easy test if you have equipment. At night the flicking will be easier to see - it might not be visible in daylight. Most alternators are 51-55 Amps - old generator was only 30. Larger ones are made (90, 120) but probably not needed unless lots of electrics like AC fans, music amps, seat heaters and high wattage head lights.
This might be helpful--I found a little device at an auto parts store that plugs into the accessories socket (formerly the cigarette lighter socket). When you turn the key (before starting) it reads the voltage in your battery. After you start the engine it shows the battery voltage when running and us higher because of wthe voltage being added by the alternator.
These units are very inexpensive and give me a feeling of confidence knowing the condition of my both my battery and my alternator. Get one for yerself and be in the know.
That is a great idea, and if it's that small it should fit into one of your on-board tool bags.
Typically, that light comes on when the voltage difference between the battery and the alternator is somewhat close, meaning that the alternator isn't contributing much to charging the battery. It will sometimes glow faintly at night if the alternator is just loafing along or if the connections are corroded or something. The only way to cure the connections is to shine them up, including: Both Battery connections, battery cable at the starter, both connections on the alternator, the connection at the indicator lamp in the Tach and the +12V feeding the other side of the dash indicator, and the ground cable between the transmission and the chassis.
If THAT doesn't cure it, then you can have someone (an automotive electrical shop) do a load test on the alternator (usually $25 bucks) to see if it's putting out proper voltage under load (which Jack's voltmeter can do, if you turn on everything in the car while it's running - the Auto shop uses a big-ass resistor as a load).
The only way to tell what's going on is with a voltmeter, used as Jack mentions. The "resting" (non-running) battery voltage should be around 11.4-11.9 VDC. The running (say, around 3K rpm) voltage should be 2 volts higher, or around 13.5-14.2 volts. All of those voltages can be tested anywhere that you can find 12 volts - a "Power Plug" would be perfect.
Let us know what you find for a volt meter like Jack mentioned. Sounds like something I could use in my tool bag.
This was my symptom. I first spent all kinds of time looking for loose or corroded wiring, I replaced the internal regulator, checked the brushes and they were good. Nothing. Still didn't work. I replaced the alternator and that fixed it.
As Gordon mentioned above - my alt. was putting out very weak voltage causing the dim glow. And because I am an idiot I did spot it and became alarmed. The idiot light worked perfectly.
I very good thing to do is have the studs pulled out where you mount the alternator stand and use bolts instead. This makes it a snap to pull the alternator and fan assembly down the road if need be.
I had flickering voltage light on my SeaDoo jet boat. Since battery was 5 years old and wouldn't hold charge, I replaced it. Although touted as maintenance free, it was very low on electrolyte - added distilled water and now have a good backup battery. You have to remove the top caps to check the electrolyte level. A cheap glass specific gravity tool will tell if a cell is weak and not getting charged. Worth checking the battery when you shine up the cable connectors. Add the chemically treated felt rings under the cables to prevent corrosion.
CB was no help. It took me a while, but I finally found a voltage regulator for my Bosch alternator P/N. I went ahead and ordered in JIC. I figured it was just a matter of time. Also, I ordered the pulley that Gordon recommended (info obtained via Joe Fortino). I figure while things are apart it would be good time to upgrade my pulley too.
FWIW, this is the P/N for my alternator http://store.alternatorparts.c...sch-alternators.aspx
Just received handy dandy powerpoint meter and checked out Natalie. Battery voltage just under 12, but alternator output at 13.75. Me thinks it's just the battery.
I knew Lane had upgraded his battery so I gave him a call. I'm following his lead and replacing my stock battery with this. Thanks Lane!
Out of curiosity, why did you go with the Odyssey extreme and not a red top by Optima?
I don't know much about batteries, so I guess I'm wondering if there was a reason or if it was just 'go with what you know'.
Thanks
Ted
I like the Odyssey because it's very small and light and can be located anywhere because it doesn't release fumes and can be in any position except inverted. The Odyssey weighs a whopping 14 lbs and is less than half the size of an Optima or a lead-acid battery. Also, I had bad luck with an expensive Optima in my DD. My Odyssey has lasted 5 or 6 years with no apparent degradation in performance.
That looks like an excellent price for the Odyssey. I paid over $100 for my lead acid deep cycle boat battery a couple years ago--60 lbs+, I think. I use that in Bridget, and the tray is up front and I don't mind a bit of ballast there.
That looks like an excellent price for the Odyssey. I paid over $100 for my lead acid deep cycle boat battery a couple years ago--60 lbs+, I think. I use that in Bridget, and the tray is up front and I don't mind a bit of ballast there.
I will add that I'm nuts about Amazon Prime. Their prices are almost always the best and I get free two-day shipping on everything. For something heavy like a battery, that's something I really appreciate.
Reminds me of the days of happy diesel truck ownership.
Replacing BOTH high-amp, deep-cycle batteries was a tad over $300 bucks... And that was at CarQuest (Interstate batteries).
You know.......I don't miss that truck!
Reminds me of the days of happy diesel truck ownership.
Replacing BOTH high-amp, deep-cycle batteries was a tad over $300 bucks... And that was at CarQuest (Interstate batteries).
You know.......I don't miss that truck!
I hear ya', Gordon. I bought my first diesel work truck in 2002. A business associate told me, "it's gonna' be love/hate". I've had at least one daily use diesel or another for the 12 years since.
I laid on a parking lot last winter changing the lower battery in the mighty Powerstroke (the second one in 3 years). I've been stranded by the side of a state highway at night, because I was 10 miles from the nearest (open) diesel pump. I've shelled a vacuum pump halfway to Salt Lake City, and driven in with no power assist on the brakes (towing a 24 ft enclosed trailer). I've had the entire fuel rail rebuilt becuase it was leaking oil (yeah, Ford uses oil pressure to drive the injectors in the 7.3). Every time I've taken any of them in (and I mean EVERY time), it's $1000 bucks, minimum.
Ford, Mercedes, didn't matter. I love 'em. I hate 'em.
I just bought a new truck. It's gas. I may buy a one ton tow pick-up with a Cummins if I absolutely must-- but for a "daily" work-truck, I'm done.
I wanted a 3/4 ton diesel to pull my new 5th wheel, but couldn't pass up the great deal I got on a 1999 Ford F250, with a V10. The truck is in excellent condition and I got it for less than I would have paid in taxes on a new 3/4 ton diesel.
After reading up on diesels, I think staying with gas was a good decision, but man, it's one thirsty beast.
Okay, the meter led me to believe that it was my battery and not the alternator. So, why not upgrade? Thursday, I removed the old battery and battery tray and the humidity did me in (I can sympathize with Lane a little).
This morning, I started fresh and installed the new battery and bracket and put everything back together.
Turned the key on and nothing. Completely dead.
- Battery is charged
- I measure continuity between battery ground and engine block
- I measure continuity between battery positive and alternator B+
Not sure where to go next. I do have a battery cutoff switch (dumb idea on my part). I'm wondering if that's the culprit.
Still don't think it's the alternator. Funny that a battery swap would completely kill it off. My only thought is that by tugging on the battery cables, I finally broke the connection on the other end. If the feed goes from the B+ to the battery cutoff switch, that could be the issues.
Before I get dirty again, looking for diagnostic clues.
Request a visit from your local automotive electric service shop.
You've screwed around with it long enough.
I'm stunned Gordon. I thought you, of all people, could give me some clues. Don't think I could get anybody to make a house call and don't feel like having it towed anywhere yet. There's got to be something else I can look at.
Going to crawl under and take a look at the battery cutout switch later this evening.
Now I know my battery kill switch is a low side switch. Had continuity across the switch and a good solid ground to the frame immediately after the switch. Not the issue. Also checked ground strap while was there. OK
Pulled off back wheel to get closer look at high side connection to starter. Positive cable was cleverly wrapped around a tube to give some added strain relief. No visible issues here either.
Verified that I'm not losing my mind and connected the right posts of the battery.
Pulled the fuse box cover. All fuses look good.
Inspected the wires to the ignition switch that looked good too.
Done for tonight.
Next step is to check continuity through ignition switch.
If you are asking for advise, Tom-- stop reading continuity, and start looking for voltage.
Check across the battery. Check at your ignition switch. Check at all the usual places. Start at the top of the diagram and work your way down, looking for voltage. When you find where there isn't any (but should be)-- that's your problem.
Thanks Stan. This is getting old fast. I had a slight intermittent failure until I changed my battery. Now I have a hard failure. I'm trying to figure out how changing the battery could have caused that. That points me to something in my battery cables. I'm going to take a harder look at them tomorrow.
