No charge!

Dave3066

Dave3066

Well-Known Member
Evening Gents

On my way home from work tonight my ignition warning light came on and the ammeter dropped into the -ve region. I got the car home and had a look at the alternator to find this:







Now I think this looks pretty terminal (sorry that's a bad joke :? ) and I might need a new alternator. Does anyone have experience of this and if it can be repaired? Perhaps more importantly does anyone know what might have caused it? Is it just corrosion leading to arcing then eventual breakage?

Any advice would be gratefully received.

cheers

Dave

Update! After a bit of searching the net it appears that this is the brush holder and is replaceable....can someone confirm?

Cheers
 

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I'd get the alternator off, then dismantle it until you can get the part of the broken terminal out, then you can try and locate the parts. Parts for the 11AC are still available, but whether the parts you need are you won't know until you get it apart and start looking for what you need. If you get to that stage I can give you the name of a good supplier who has a shop but also trades on ebay and I know he stocks at least some of the parts for the 11AC, including the brushes, brush holders and bearings.
 
If only I had the luxury of being able to take the time to source parts for it.....which I don't as this is my everyday car. I think the broken threaded terminal is the end of the long bolt that holds the whole thing together and I suspect they are like a rocking horse excrement to get hold of.

I think I'll just replace the alternator and see if I can recondition this one slow time.

Thanks for the advice Harvey.
 
If am sure Ian Will have a spare but failing that there is a guy who breaks P5 I know that certainly will. The 11ac was the norm for them.

I will PM the details. If you had the time it is worth changing to the lucas A127 as found on Fords and many others Mine was brand new from ebay £18 inc delivery. with a few wiring mods it fitted straight on.

Maybe worth a call to these guys.http://www.woodauto.com/default.aspx

Colin
 
Gents

Having now fitted my recon alternator I continue to have problems charging.

When first fitted, the ammeter showed that it was charging but the ignition light stayed on. Not a problem I thought, that should just be an indication problem such as a bad connection on AL. Anyway, after a half hour journey with the ignition light on but the ammeter showing a charge, the ignition light suddenly went out. Great I thought. Next day the same again. Car started, ignition light stayed on but this time no charge showing on ammeter. After half an hour light went off, charging again. Much scratching of head. I decided to go through as many of the checks listed in the workshop manual as I could.

First problem was trying to find the 6RA relay. The one I thought it was (under the bonnet on the offside inner wing) turned out to be the solenoid relay. I found this out after the starter turned when I shorted across C1 and C2. OKay then maybe it's the one in the passenger side glovebox. But if that's the case then where is the heated rear window relay? My wiring diagram on 86.00.01 Sheet 2 does not show a 6RA relay anywhere in the alternator circuit.

Anway back to the car. I disconnected the large connector from the 4TR to do some checks there and when I reconnected it the alternator showed it was charging again. Another symptom of this fault is that my 3AW chatters all the time at all revs. Previously, with the old alternator it chattered at very low revs only.

So if someone can confirm the location of the 6RA relay (and the heated rear screeen relay) for me I'd be most grateful.

ps my car is a '72 3500S chassis suffix A

Cheers

Dave
 
Tony

Thanks for the reply.

Yes that's where I think mine is too, but that is contrary to all the wiring diagrams. What model, year and chassis suffix is your car?

I will check that particular relay on my car tomorrow when it's light. I'm just slightly baffled by the fact that the alternator fault has now developed to show completely different symptoms. Today whilst I was running the car and doing some checks I disconnected the 4TR voltage regulator and when I reconnected it the ignition light went out and the ammeter showed a charge. I stopped the car for about 10 mins and then went for a run of about 12 miles, during which the ignition light was out and the alternator was charging fine. I left the car for about 10 mins when I got there and when I started it up again the symptoms were back (ignition light on and and no charge). I'm starting to get a bit irritated. Could the 4TR regulator need adjusting for the new alternator?

Dave
 
Update

The alternator is not charging at all now. I have checked all voltages and relays that I can find and they are ok. The relay in the passenger glovebox on my car is for the heated rear window and the wiring for the charging circuit is as shown in the manual. I've checked all wiring for continuity and it's all ok. I get 12V onto the alternator field terminal and the voltage regulator when the ignition is turned on. All earths are ok and there are no shorts or alternate earth paths. I now have the battery out to charge just in case it is not now generating sufficient voltage for the alternator field coil. However, I would imagine that this would be overcome by jump starting the car which I have done twice now. Still no charge from the alternator and I'm starting to suspect the alternator is at fault, even though it is a 'new' reconditioned unit. I'll be speaking to JRWs tomorrow for some advice on that. My only other option is to try a new voltage regulator as it's the only component in the circuit that hasn't been changed (I replaced the 3AW relay a few months ago and I believe that is only for indication of the ignition light so shouldn't prevent the alternator charging). I might have access to another alternator to try over the next few days but failing that I'm stumped. I don't have a moving coil meter to check the current output of the alternator and my DMM only goes up to 10A.

If anyone has any suggestions please fire away.

Dave
 
Check the connections at the dongle where the battery cables join under the carpet under the drivers left foot. They can corode particularly if the carpet gets wet.
My car is a 71 2000 auto
 
Dongle checked and ok. It's nice and clean and corrosion free. Besides I would have thought if there was a problem there it would affect the starter too but there are no problems on that front (apart fromwhen the battery is flat :shock: ). I reckon the wiring is fine I think it's a component problem..... but you never know with these cars :!:

Cheers

Dave
 
The brown wire to the alternator had rotted off on mine stopping charge, the ignition feed and starter are fed by seperate wires from the donge.
 
necpwa said:
The brown wire to the alternator had rotted off on mine stopping charge, the ignition feed and starter are fed by seperate wires from the donge.
Click to expand...

Mine has a thick white and brown wire which is fine and showing battery voltage.

I'll give the battery a good charge overnight and see what it does in the morning.

Cheers

Dave
 
Gents

My battery charging saga continues. I have now fitted a new (recon) alternator, a new voltage regulator and a warning light control unit. The alternator does now charge the battery, but it only kicks in after between 5 - 10 mins running. I spoke to JRWs this morning and he is convinced there should be a relay in the circuit too. This would fit the symptoms as it's almost like a switch being flicked on after 5 - 10 mins running when the alternator kicks in. However, the only relay I can find is the one fitted above the voltage regulator in the passenger glovebox. It's marked 33213J 6RA 12V (4 connectors W1, W2, C1, C2) and as far as I can tell it operates the heated rear window. JRWs seem convinced that these cars had the heated rear window wired straight through the switch but mine is definitely wired through a relay (as it says in the wiring diagram). To check this relay had nothing to do with the charging circuit I disconnected it with the engine running and the alternator charging and it had no effect on the charging circuit.

So, if there is a relay in the circuit I cannot find it. The only other 6RA relay I can find on the car is under the bonnet attached to the offside inner wing. This I'm pretty sure is the starter solenoid relay and, unless someone tells me otherwise, has nothing to do with the charging circuit. If it does, then how? Clearly that relay is working as the car starts fine?

Please help. Someone out there must know if there is another relay in the charging circuit and where it is. I can't find it on any of the parts diagrams either. If I get no joy then I'll be tracing the complete charging circuit wire by wire to see where they go and what is attached to them.

cheers

Dave
 
I've had a little looky in the booky, as a refresher course, and early cars had a 6RA relay to isolate the 4TR control unit when the ignition is off, but that was deleted before the introduction of the 3500S, so your car shouldn't have one, but the same function is still required and so the relay was replaced by a pair of contacts in the ignition switch. So my understanding would be if those contacts fail to close when you operate the ign switch to start the car you will lose the feed to the 4TR and hence it won't charge. I would suggest running the car with the 4TR unit still connected, but with a test lamp between the "+" terminal and earth, you should have the test light illuminated, but with your problem it may not be due to the ign sw contacts failing to close. Leave it running and see if the test lamp comes on after the 5-10 minutes when it starts charging.
If so problem solved. (We hope!)
 
harveyp6 said:
I've had a little looky in the booky, as a refresher course, and early cars had a 6RA relay to isolate the 4TR control unit when the ignition is off, but that was deleted before the introduction of the 3500S, so your car shouldn't have one, but the same function is still required and so the relay was replaced by a pair of contacts in the ignition switch. So my understanding would be if those contacts fail to close when you operate the ign switch to start the car you will lose the feed to the 4TR and hence it won't charge. I would suggest running the car with the 4TR unit still connected, but with a test lamp between the "+" terminal and earth, you should have the test light illuminated, but with your problem it may not be due to the ign sw contacts failing to close. Leave it running and see if the test lamp comes on after the 5-10 minutes when it starts charging.
If so problem solved. (We hope!)
Click to expand...

Thanks Harvey.

That's a start anyway. At least now I know there is no relay.

From previous checks I've done I know that there is 12V at the 4TR +ve terminal with the ignition on (ie with ignition lamp on). My 4TR has 4 terminals in all, 2 +ve terminals, one is a single wire (red/purple from memory) the other goes to a 3 terminal block with the -ve and F. I worked the symptoms in reverse when the alternator was charging to see what would stop it charging and disconnecting the single wire from the +ve (supply) does just that) hence why I bought and tried another 4TR but that made no difference. The original one is back in and incidentally, the replacement was different from the one fitted. The one fitted was different on the rear to the replacement. I'll post some pics when I get a chance but my old one had no adjustment and didn't have the long rod device fitted horizontally in the upper half. When I connected the replacement to the supply and turned on the ignition this rod got very hot and started smoking :shock: . This tends to indicate something is wrong but it may have been due to the lack of load on the device. I might try it again with the device loaded and see what happens. Not sure if this one is now damaged :?

Ok so I popped out of the office to try your suggestion. With a test bulb connected between the 4TR positive and a suitable earth point I get illumination with the ignition on. When i turn the key to start the engine the bulb goes out but then comes back on again when I release the key after the engine is running.

Where's that drawing board?

Cheers
 
necpwa said:
what colour wires are conected to the relay?
Click to expand...

Tony

The relay in the passenger glovebox has a black earth wire, and a positive supply that comes on with the ignition (not sure about colour). These are connected to W1 and W2. C1 and C2 have thick (ish) brown/white wires. Have discounted this relay now following Harvey's post.

My understanding of how the alternator works is that as long as there is a 12V supply to the field windings to create the electromagnetic field (which there is) and the alternator is spinning then it should be generating voltage and current flow to the electrics. This is basic generator theory and I've checked the supply to the field windings at the alternator F and -ve connectors. This comes from the voltage regulator, which regulates the voltage on the field windings, thereby regulating the strength of the electromagnetic field and the output from the alternator.

My next step will be to take the car to an auto electrician in the hope that he can directly measure the output of the alternator. Or see if I can get hold of a suitable moving coil ammeter to do it myself.
 
I found these diagrams in a Lucas fault finding guide:





Interestingly, these show that the field supply for the alternator also goes to the starter solenoid relay. I wonder if that might be dragging the output down?

Hmmmmmmmm. Of course this is a generic diagram and my car may not be wired the same, but it's something else to consider.
 

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Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaarrrrrrrrrrrrrrrrrrrrrrrrrghhhhhhhhhhhhhhhhhhhhhhh

Drove all the way home from work, about 40 mins, with no charge. Carried out a few checks with the engine running when I got home, still no charge yet all voltages ok. Stopped the engine and started it again and the damn thing started charging straight away. Went out to Tesco to do big christmas shop and to get some charge in the battery, a half hour drive. Shopped till we dropped, got back to the car, no charge all the way home :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil: :evil:

I'm convinced it's the alternator as it was all working perfectly well with the old one before the main battery feed dropped off through corrosion. I've had nothing but trouble with the recon one since I fitted it. So it's going back!
 
Okay, now that I've calmed down a bit and got my brain back into gear I think I've thought of a way to test the output from the alternator without using an ammeter :idea: . After looking at the wiring diagram again last night I'm going back to the dongle theory first suggestd by:

necpwa said:
Check the connections at the dongle where the battery cables join under the carpet under the drivers left foot.
Click to expand...

The alternator may be working fine but if there is an intermittent break in the cable back to the battery then that might explain the charge/no charge I'm getting. I think I've found another path for battery voltage to get to the main battery feed on the alternator which might be throwing me off the scent. Anyway if I'm right then if I start the car, connect a jump lead from the main battery feed on the alternator straight back to the battery +ve (effectively bypassing the car's wiring) and measure across the battery terminals then, provided the alternator works, I should get the expected 13-14 volts to charge the battery.

The jump lead should be beefy enough to take the current.

The theory seems sound, can anyone see any problems with trying this?

Dave
 
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