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TR2/3/3A dead battery, generator, belt

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2billydavies

2billydavies

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hi everyone,
so my 58 TR3a has been running perfect for months. almost driving it daily to work, blah blah blah...
however, the last week during a midnight trip to the beach the serpentine belt started slipping, smoking like crazy, melting, and eventually dying. It didn't rip in half, so I did make it home,
but I had to replace it. No big deal, took 2 minutes.

My first trip in the car after the new belt install was fine. But I started noticing that with each time I started it, the battery sounded weaker, and weaker, and weaker... until the other day, it was dead.
This is a brand new battery. Bought it 4 months ago. Nothing wrong with the battery. I also noticed, after the belt install, that that when I had the headlights on the battery charging gauge was slowly but surely
going down into the negative rather than staying the middle or a little on the plus side. So the battery dying wasn't really a surprise as much as it was a disappointment. I knew it was coming.

So my question is this: Could the stress from the belt melting, stripping, and burning up somehow affected my generator? I believe the issue is the generator is dead. I did notice, when I was installing the new belt, that
if I spun the pulley on the generator counter clockwise, there was a distinct "buzzing" sound coming from it. Only counter clockwise, though. There was no sound at all when spun clockwise. I never noticed this buzz before so I'm thinking
that may have something to do with it.

In any case, any thoughts on this? Anything else I should check before buying a new one??

thanks!
 
Something made the first belt "self destruct", i.e. slipping, pulley locking up, etc. I would first put on a good belt and make sure the tension is adjusted on the generator so that any slack is taken out of the belt. I assume you have just a regular belt and no modifications or addition have been put on the car, so that you have the belt going from crank, to generator and water pump. Check that all are moving and no wobble. Check ammeter for positive charge. If not charging you probably do need a generator. I had a bearing go out on an MG. Everything looked fine but it didn't charge.
 
The generator and control box have a very intimate relationship; a failure or even misadjustment in one can make the other look bad. So in most cases, I would suggest running through the tests, which take only a few minutes and will tell you for sure what's wrong.
https://drive.google.com/open?id=0B2H2NJt34OffNTc3ODkwYzAtYjRlYS00NDNmLWI0YTYtNjY5ZjQxZTA2NGFm

However, the one-directional 'buzzing' suggests to me a field winding that has come loose and is rubbing on the armature; or some other mechanical failure inside the generator. Personally, I would open it up to see; but if you're not interested in possibly repairing it (or having it repaired), a new generator might be in order.

BTW, the original belt was not a serpentine belt. Unless someone has done something very strange (TR3 with power steering?), your belt is an ordinary V belt. Just somewhat thicker than most cars use :smile: Gates actually makes a cogged version of it (for truck applications) that I like a lot better than the solid belts generally sold by TR vendors. I don't have the number handy, but RockAuto has them listed by application (and good prices). Lots easier to install, and at least in my experience, lasts a lot longer.

Also, there were two different generators used on the TR2-4; the later unit was introduced around 1960 and is slightly larger (both electrically and physically) than the earlier unit. Most vendors seem to supply the later unit even for earlier applications (it bolts right up, though the terminals are different configurations); but Lucas warned that the control box must match the generator. I don't know what the ill effects of mixing a later generator with an early box would be; but I'm guessing they had a reason.
 
I've had so many generator issues over the years on my 59 that I finally bought an alternator kit. Might be time to consider that upgrade.
 
thanks for the reply. Well, to answer your belt comment:
My father, who gave me the car a few years ago after owning it for about 30 years, had a belt on there. Not sure if it was really an issue considering the car ran perfectly with this belt for years and year.... but it was a lawnmower belt. lol. no clue why he did it that way. i'm guessing because he lives in the mountains of PA and the nearest auto parts store is an hour from his house and he had a lawnmower belt lying around. But that's what was on there.

I'm not real sure, why and out of nowhere, it decided to slip and melt and burn up the other day.

I'm going to go through some tests everyone recommended. I bought a new belt for it (much, much different than this lawnmower belt, lol) and put it on already. tension is fine, works perfect. But the battery died pretty quickly.





TR3driver said:
The generator and control box have a very intimate relationship; a failure or even misadjustment in one can make the other look bad. So in most cases, I would suggest running through the tests, which take only a few minutes and will tell you for sure what's wrong.
https://drive.google.com/open?id=0B2H2NJt34OffNTc3ODkwYzAtYjRlYS00NDNmLWI0YTYtNjY5ZjQxZTA2NGFm

However, the one-directional 'buzzing' suggests to me a field winding that has come loose and is rubbing on the armature; or some other mechanical failure inside the generator. Personally, I would open it up to see; but if you're not interested in possibly repairing it (or having it repaired), a new generator might be in order.

BTW, the original belt was not a serpentine belt. Unless someone has done something very strange (TR3 with power steering?), your belt is an ordinary V belt. Just somewhat thicker than most cars use :smile: Gates actually makes a cogged version of it (for truck applications) that I like a lot better than the solid belts generally sold by TR vendors. I don't have the number handy, but RockAuto has them listed by application (and good prices). Lots easier to install, and at least in my experience, lasts a lot longer.

Also, there were two different generators used on the TR2-4; the later unit was introduced around 1960 and is slightly larger (both electrically and physically) than the earlier unit. Most vendors seem to supply the later unit even for earlier applications (it bolts right up, though the terminals are different configurations); but Lucas warned that the control box must match the generator. I don't know what the ill effects of mixing a later generator with an early box would be; but I'm guessing they had a reason.
Click to expand...
 
2billydavies said:
So my question is this: Could the stress from the belt melting, stripping, and burning up somehow affected my generator?
In any case, any thoughts on this? Anything else I should check before buying a new one??

thanks!
Click to expand...

More likely the bad generator killed the belt.
Tom
 
Check that waterpump turns freely.
 
A word of caution on the belt tightness--. The belt should only be tight enough to keep the belt from slipping. BUT IT SHOULD NOT BE VERY TIGHT. Having a regular belt on the car will provide a lot more traction to keep the belt from slipping. But a tight belt will KILL your water pump bearing as well as the generator bearings. Once you have the generator problem worked out, you should check the belt tightness to allow about 1/2 to 3/4 inch flex in the belt when pushing on the belt between the water pump and the generator.
Charley
 
A couple points:

1. A belt really should not slip to the point where it burns up. It's hard for me to see than happening unless something is wrong in the generator or water pump, causing excessive resistance. Whatever does that could be intermittent, or worse under load.

2. I think it's unlikely that the slipping belt damaged the generator, but very likely that the generator failed somehow and caused the belt to slip.

3. Randall's suggestion of a loose field coil is a real possibility. Also a bearing problem. Or, it could be innocuous. Sometimes, as the brushes wear, they will make a SLIGHT buzzing noise if you spin the armature backwards, and no noise when you spin it forwards. How much resistance to motion is there? If it is anything worse than nice and silky-smooth, I think it's time to pull the generator apart, check the bearings, and see if there is any sign of the armature rubbing on the field poles. The clearance, remember, is very slight. And, if it is, the reason might be a bad generator bearing.

4. I'm not a great believer in coincidences, but it's possible that the control box is failing, too. It's plausible, but not likely, that a failed box could have increased the load on the generator, causing the belt to slip--especially if it wasn't the right belt. Going through the check and adjustment procedure in the shop manual will tell you quickly if there is a problem.
 
My generator is doing exactly like you say.. .. Just a slight buzzing or clicking noise whwn spun counter clockwise. There is no resistance at all. Spins nice and smooth, both directions.
So if that's the case, that the generator is OK.. .. Then it must be a coincidence that the charging system died on the same day at the same exact time as the belt? Lol. I'm not a believer of coincidence either. I'm going to run though some checks.

I do however, believe I put the new belt on too tight. I'm glad that was mentioned above. Definitely going to check that out. Is there any possibility that that is the reason it's not charging well? (or not at all)?
 
Bearing wear from running the belt too tight usually takes some time to develop, doesn't happen instantly.

But one possibility is certainly that the rear bearing is worn out (perhaps from running with the belt too tight, or even from the makeshift belt flapping around at certain engine rpm). That can let the armature drag on the pole pieces when side force is applied (a combination of load from the belt and magnetic attraction between armature and pole pieces when full field current is applied). Usually, that makes enough racket to notice before it locks the belt, but your makeshift belt might not have had as much grip as the stock setup.

Also be sure to check the lower generator mounts. I've seen a lot of them work loose and let the generator flop around, which can cause strange problems sometimes. I've found the pedestal damaged (from working loose) on every TR3 I've worked on; and every generator has damage to the mounting holes.
 
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