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Charging problem *again*

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MadRiver

MadRiver

Jedi Knight
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Howdy all. The weather in DC was in the low 50s, so I decided to take Greenie for a spin. I start him up, wait for him to warm up a bit, and then off I went with the lights on (it was cloudy) and the heater going full blast. I noticed that I was discharging pretty consistently, so I turned off the heater and the lights. I then started charging constantly. I was in stop and go traffic, so I never really had a chance to open it up for a long period of time, but I doubt that a ran the battery down that much, and I have a suspicion that my mysterious charging problem has resurfaced. Thankfully my battery was nice and cool, so perhaps I did discharge it a lot with all the eletricals on, but I'm getting tired of this. Might be time for a modern alternator. /ubbthreads/images/graemlins/confused.gif
 
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... I went with the lights on (it was cloudy) and the heater going full blast. I noticed that I was discharging pretty consistently, so I turned off the heater and the lights. I then started charging constantly...

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Sounds more or less normal too me. Unless you expect to do a lot of night-time/wipers/heater driving or want a killer stereo set-up or heated seats your stock dynamo should be able to keep up.
 
MR,The low 50's is really not that cold. However, at these lower temperatures the battery's capacity is reduced. Further, not running the car long distances regularly has a similar effect.Combined this could have reduced your battery capacity significantly.--Keoke
 
Doesn't sound like a problem; sounds like normal operation. Try to get on a road where you can let 'er out.
 
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Might be time for a modern alternator. /ubbthreads/images/graemlins/confused.gif

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I vote for the alternator upgrade, unless your 250 is concours and you don't want to go with non-original. Now that the engine is out of my car, I can take a series of pics to let you see how mine was installed, from angles that were not possible with the engine in the car.
 
I am with you, Bill... My next "big" project is a GM alternator conversion.

I currently have the original alternator in the TR right now, and as of a few weeks ago, I am not getting a charge past 12 volts... usually hovering at about 11.5 while on the road.
 
Sounds as if you're running on battery alone, Aldwyn. Alternator is now just a belt tensioning pulley. The GM unit swap is in order. I've done this on several Jaguar 12's and a few other LBC's. 14.5V is a "wonderful thing"! /ubbthreads/images/graemlins/wink.gif
 
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Sounds more or less normal too me. Unless you expect to do a lot of night-time/wipers/heater driving or want a killer stereo set-up or heated seats your stock dynamo should be able to keep up.

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It certainly keeps up when I don't have any of the accessories on. So, I'll keep an eye on it. Battery is new, but I may swap it out to see if that makes a difference.

Thanks as always, gang!
 
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Sounds more or less normal too me. Unless you expect to do a lot of night-time/wipers/heater driving or want a killer stereo set-up or heated seats your stock dynamo should be able to keep up.

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It certainly keeps up when I don't have any of the accessories on. So, I'll keep an eye on it. Battery is new, but I may swap it out to see if that makes a difference.

Thanks as always, gang!

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Geez, I hope you don't consider HEADLIGHTS as accessories.
 
Bill, I've got some genuine Lucas headlamps that will definitely not overdraw the electrical system! /ubbthreads/images/graemlins/grin.gif
Jeff
 
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Geez, I hope you don't consider HEADLIGHTS as accessories.

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That's why they call Dr. Lucas the Prince of Darkness! /ubbthreads/images/graemlins/lol.gif

Actually, I do have original Lucas lamps. I sometimes think about adding fog lamps, but I think it would suck every electron of electricity out of the system.
 
I'd hook a temporary voltmeter to the battery...run the wires thru the firewall, and do some driving to get a "second" opinion.

My last TR3A always showed no charge or discharge for 13 years yet the battery never failed and the car always started.

One of the major reason's trucking companies buy new class 8 trucks with a minimal amount of gauges is that the drivers constantly gripe that the "front diff is too hot" or "the oil temp gauge shows a low temp" and such.

The mechanics spend countless hours trying to repair stuff that isn't broken. Now they give a guy a tach, speedo, oil pressure, water temp and battery gauge..oh yeah, an air pressure gauge. They have to keep it simple.

My Pete has 21 gauges...the average guy would always have something that's "just not right" if he has all of that to look at.

Sometimes we get pretty anal about all the details of our cars when all we SHOULD be doing is driving them..
 
Howdy Yankee TR -- it's not the discharging that's really bothering me. It's the charging that concerns me when none of the other electricals are on -- I don't want to cook my battery. But your advice is sound -- I've also had that tought as well.
 
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Howdy Yankee TR -- it's not the discharging that's really bothering me. It's the charging that concerns me when none of the other electricals are on -- I don't want to cook my battery. But your advice is sound -- I've also had that tought as well.

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Bill,

I wasn't being critical just to let you know...it was just an observation. I used to be so darn picky...now, late in life, I'm just happy to have SOMETHING neat to drive...in just about ANY kind of condition!

I don't have enought time left to be so demanding... /ubbthreads/images/graemlins/devilgrin.gif

Rick
 
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It's the charging that concerns me when none of the other electricals are on -- I don't want to cook my battery.

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This is how it's supposed to work - no need for concern. The generator or alternator voltage is set to be higher than battery voltage; therefore, it will always charge the battery. Unless you have turned other loads on that steal current away from the battery. The deader the battery, the higher the charge current. As the battery charges, the charge current should drop, but will never cut off entirely unless other loads are on. Unless the voltage regulator...er... control unit voltage is set too high, you won't cook your battery. If it cooks, it was bad anyway.
 
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Might be time for a modern alternator. /ubbthreads/images/graemlins/confused.gif

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unless your 250 is concours and you don't want to go with non-original.

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Hi,

The GM alternator is a pretty easy modification. However, if you want to keep things looking relatively stock, I believe someone in England is making an alternator in disquise that looks very similar to the original generator.

Besides the typically higher output to handle heavier loads on the battery, another difference between alternators and generators is that alternators begin to produce a steady charge at much lower rpms. So a car driven at modest rpms for a short time may see the battery discharge, but should be fine with an alternator.
 
Hey Bill. I see the engine is out of your car. Could you post some pics of your alternator upgrade, or PM them to me? Especially ones with any modifications to the alternator would be helpful. Thanks for your help, David K.
 
Bill, that would be a great post for the knowledge base. Please do it before it all goes back together.

Thanks in advance,
 
David, her are a couple of pics of my Autozone Delco-style 65 amp 3-wire (not one wire) alternator. Same alternator that would go on late 60s Chevys.
You will have to grind on the case a bit for it to snug up to the stock bracket on your block. I thing I had to grind on my stock bracket as well. Sorry to be so vague about where to grind but I pretty much eye-balled it, making sure that the pulleys lined up (used a yardstick and good eyesight).
You will see that I found a good stout bolt to fit between the alternator and the bracket. I may have had to ream one or the other so they were the same size. (boy, I am a lot of help here.) I used an all-metal locking nut on the bolt so I could loosen a few times as needed and the nut won't wear out. I went with a long bolt so I could locate it in the dark with a deep socket. Unfortunately, all I could find that fit the bill was a metric bolt (now I have a metric bolt on my TR6).
The next thing is go to any auto parts store and buy the chrome-plated universal alternator bracket that you see on mine. It <u>was</u> chrome but you will have to shorten it and grind on the lower arch for the fan to clear. Not a biggie, you will figure it out. I ground the rest of the chrome off and painted it.

The rest of the alternator support (that lower bolt is quite stout and is stronger than you think) is this bracket, which you bolt to the top of the alternator. I actually tapped the hole in the alternator and got the appropriate bolt to screw in, a little more secure this way.

I had to use the pulley off my Lucas because the pulley on the Autozone was 3/8", I needed 1/2". Use an impact wrench to take the pulley nut off, otherwise you will never get it off without busting something.


Get the alternator clocked to fit your wire location, they will do this at Autozone. Hit and miss on the pulley size, I just guessed, bought several and returned the ones that didn't fit. Then bought an extra for emergencies.

That's it.

alternator1.jpg

alternator2.jpg

alternator3.jpg
 
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