My Car Breaks Alternators! Please help

Discuss Electrical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
BenDixon2002
Minor Friendly
Posts: 20
Joined: Sat Feb 22, 2020 7:48 pm
MMOC Member: Yes

My Car Breaks Alternators! Please help

Post by BenDixon2002 »

Hi all.

I got my Morris Minor five years ago and have been daily driving it since (it’s my first car). I have done an alternator conversion due to how often I use the car, plus I have halogens fitted, a speaker, USB port.

I’m writing this post from the hard shoulder on the M62, because once again I noticed lights dimming, and indicators flashing very slowly. I pulled the starter and no life in it. Battery is at 9.8V testing with my multimeter. My fan belt is not slipping. :cry:

This is a pattern which I can now consistently predict will happen every 9 months or so, and I only average 2.4K miles a year. What I would do is then charge the battery, and replace it with a Chinese made Lucas-type alternator ordered from a reputable well known Morris parts supplier. I have been through at least five of these in 12k miles of ownership. Eventually instead of replacing the whole unit I would just replace the regulator, which would temporarily fix the problem for a few months (back up to 14V) and then fail.

This last April 2024, it went again, so I thought it must be the sub par quality of these Chinese alternators. I instead bought a £200+ WOSP top of the line OEM standard Lucas type alternator to try to permanently cure this issue. And I also put a plug in to cigarette lighter voltmeter to give warning of upcoming failure.

I have noticed a pattern of it working fine around 14V without headlights on in the day. Then at night when I put headlights on it will stay at 14V for a few minutes and then drop down to 12-point-something volts, and then gradually decrease. If I turn the headlights off and start it up again, I will not get 14V and it will stay the same as it was around 12V or lower depending on how far I have ran it. However the next day, with the headlights off, I will start it up and it will charge and run well at 14V again. I was able to do this on short runs for a good few months. I took it to KwikFit to get the charging system tested, and they couldn’t find anything wrong with it, so that gave me false peace of mind to keep using it. Battery tested healthy just a couple months ago.

Earlier today I did a short drive in the day and it stayed around 14V. Later on I started a 2 hour journey in the dark with lights on. Started at 14V and soon dropped down to 12.8V and then gradually dropped to 9.8V over a period of about 1hour 45 minutes driving with headlights on, then I stopped on the hard shoulder which is where I am now because I knew something was wrong and found a safe place to stop (Smart Motorway is just ahead from me!!)

Luckily this WOSP alternator is under warranty. My mates in the MMOCYM haven’t had any problems with the Chinese alternators and my car is well known with them for the failing alternators. I think that something with my car is causing them to fail, it can’t be just bad luck, especially now this expensive alternator has failed on me.

I have tested the resistance from alternator to battery positive, and fitted an extra earth wire from the engine directly to the battery negative wire at the top there. No problematic resistances on either side. I have replaced the bullet connector earths on the headlights with ring connectors to improve earthing.

I believe replacing the alternator will fix it temporarily, but I don’t trust the new one not to go again. This WOSP one,(more than three times as expensive as the ones from morris minor suppliers) has barely done 3k miles! They only last 2-3k, that seems to be the magic range for them.

Any advice? I done countless internet forum browsing over the last five years and I’m at a complete and total loss on what to do, when the next day it’s 14V again and tests come back all is well.

Thank you very much, I hope your Moggies aren’t as temperamental as mine. Hopefully breakdown will be here soon!
:-(

If anyone would be interested in taking an actual look at it I’m at Liverpool.

(As I write this I can’t post due to cellular date ip range being blocked, I will post as soon as I get home)
IMG_2011.jpeg
IMG_2011.jpeg (3.39 MiB) Viewed 16091 times
User avatar
rocco
Minor Fan
Posts: 367
Joined: Fri Jul 15, 2022 8:59 pm
Location: Germany
MMOC Member: No

Re: My Car Breaks Alternators! Please help

Post by rocco »

That is rotten luck Ben but I think you might be looking in the wrong area. I wonder if the halogens might be the cause of the problem and so if it was me, I'd put standard bulbs back in and see if the situation improves.

Common mistakes with batteries are that some people measure only the voltage, see 12-point-something volts (with engine off), and think it's all fine without measuring amps/resistance. I can't be sure but I think my battery is rated at something like 540cca. If I measure it and find it's down to below 400 then I'd start thinking about a new one.

Can I ask what Kwik-Fit did to test the charging system? What exactly do they test please?

I hope you get the bottom of the problem soon. I am sure that one of the more qualified chaps will be along shortly to give you some proper diagnostic tips and hints.
1961 Morris Minor 948
1970 Morris Minor 1098
User avatar
svenedin
Minor Legend
Posts: 2443
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by svenedin »

I am still with a dynamo but this all sounds rather familiar. My car was also my first car and way back then it had a habit of not charging the battery properly. Just as you described, the headlights would get progressively dimmer and eventually there wasn't enough power to flash the indicators. I got very good at using the starting handle and giving hand signals in those days!

I think you are going to have to try to systematically diagnose the problem by a process of elimination. I would start by checking all of your wiring and ensuring that the alternator was installed correctly to start with. I am assuming you have bypassed the RB106 and kept it as a junction box? I do not know what your wiring loom is like but sometimes they are a nightmare of corroded connectors and bodged previous owner modifications. If it is VERY bad it might be better to just bin the loom and start with a new one.

Your fan belt is not slipping you say but is everything properly lined up?

Regarding your "halogens" do you just mean halogen headlight bulbs? These are no big deal and in fact use marginally LESS power than the sealed beam headlights which were used for a long time.

My last question is, why did you change to an alternator? Was the car failing to charge when it had a dynamo? Your power demands are well within the capabilities of the original dynamo. Are you sure it is not the battery that is at fault? They don't last very long these days.

Whilst bad connections and/or a faulty battery would explain the failure to charge it would not explain "breaking" the alternator or at least I can't work that out. Are you sure it isn't as simple as the little wiring loom from the alternator is faulty in some way (causing a short-circuit)?

There are various tests you could do. You could remove the alternator and wire it up on the bench to a battery. Spin the alternator with an electric drill and measure output. If you can prove the alternator is fine then the problem must be elsewhere.........

Stephen
Last edited by svenedin on Tue Feb 04, 2025 9:58 am, edited 1 time in total.
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
oliver90owner
Minor Legend
Posts: 1777
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: My Car Breaks Alternators! Please help

Post by oliver90owner »

I would suspect any cheap chinese alternator.

Then there is mis-aligned drive belt - a fault at fitment.

Over tensioned belts are another alternator killer - especially if cheap vhinese bearings.

There are only 5 elements that are likely to fail.
The rotor (never experienced) .
The stator - unlikely, unless damsged or of inferior quality.
The regulator - solid state snd either works or not - usually charging to the wrong voltage.
The diode pack - occasionally fail, but easily replaced - quality is likely a factor. The commutator/brush assembly - may fail after very high mileage, but can be affected by bearing wear and/or cheap components.

If the expensive offering was of chinese origin, I would not be overly surprised if it is simply over-priced.

I quietly suspect these multiple failures are down to human error. Wrong fitment, over-tensioned belt (often due to using a worn out belt), or buying the wrong quality alternator.
BenDixon2002
Minor Friendly
Posts: 20
Joined: Sat Feb 22, 2020 7:48 pm
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by BenDixon2002 »

Thanks for your replies.

KwikFit ran the car and measured battery voltage 14V, and then they put all the accessories on inc headlights and the battery was still charging at 14V so it passed that test. Then they put some gadget on the battery which gave them a reading of its health, can’t remember what measurements it took, but it was still in the good range. Battery is not more than 2 years old.

Yes I have bypassed the old voltage regulator and wired the alternator correctly. Some of the connectors do get a bit dirty and need cleaning on occasion, but the loom itself isn’t terrible.

I have never ran the car with the sealed beams or the dynamo. I converted it to halogens as it was a recommended electrical “upgrade” and it was also recommended to swap to an alternator if running halogens, so I assume halogens must have a higher current demand?

Since the problem only occurs when headlights are on (I think), I think the plan of action is to charge the battery, see if the alternator still works and hasn’t completely broken yet (if it has it’s still under warranty) and then swap to the old sealed beams, just to see if they too stop the alternator charging, from process of elemination.

The expensive alternator is from WOSPerformance (currently fitted), and European made.

“At WOSP we design & manufacture bespoke starting & charging systems in the UK & USA and distribute them via a dealer network. We have produced alternators, starter motors and dynators for over 40 years to the highest standards. Working with and supplying some of the industries top names such as Aston Martin, Cosworth, Dallara, Ginetta, Jaguar, Lamborghini, McLaren, Renault Sport and race series such as F3, GP3, Supercar lites Rally X and Indy lights. Albeit our roots are firmly in Motorsport we also cater for areas of the industry such as Aviation, Industrial, Marine, Plant, Agricultural, and Vintage/Classic/ Historic applications.A family-run company with a fully equipped in house CNC machine shop, we refuse to be beaten on service and quality, whilst pushing the boundaries of what is possible.

Widely regarded as the world leader WOSP offer a full range of starter motors designed to be high torque, reliable, lightweight and completely serviceable. Catering for well over 2000 different starter motor applications it is rare we don’t have the answer for what you require. Whether it is 6, 12 or 24 volt ranging between 1kW and 11kW we use different form factors to ensure easy fitment with no obstruction. All of our units are built to the highest standards using only O.E. parts and units.

Complementary to our starter motors we also produce a complete range of alternators varying in outputs, fitments, size and more. Whether it is a new high quality Lucas replacement or an upgraded lightweight CNC billet plug & play unit there’s usually multiple options. Additionally, growing in awareness our dynators which are alternators disguised as dynamos for the classic car market. Built to be the most authentic looking and reliable on the market they now produce over 200 different models.

All units are produced to BSI ISO 9002 standards.
All units have their own serial number for traceability.
The latest electronic testing equipment is used to control the quality and performance of every product.
We pride ourselves on value for money, quality and service.
Thank you for taking an interest in WOSP. Follow us on Facebook and Instagram for regular updates.”

Edd China has used them.

Thanks for your help!
User avatar
svenedin
Minor Legend
Posts: 2443
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by svenedin »

The sealed beam headlights are 12v 65/55w whereas a standard halogen H4 bulb is 12v 60/55w so in fact uses LESS power. In fact, sealed beams are halogen anyway but instead of just replacing a bulb you have to replace the whole unit.......It is incorrect that changing to H4 bulbs means you need an alternator but if you fit additional "rally" type lights as well then yes you may exceed the ability of the dynamo to keep up especially with a heated screen etc.

What halogen headlights have you fitted? What is the exact spec of the bulbs? Headlight problems are usually due to a bad earth. The earth is a small plate on the inner wing to which a bullet connector attaches from the headlight sub-loom. https://www.morrisminorspares.com/elect ... pe-p829859
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
User avatar
geoberni
Minor Legend
Posts: 4111
Joined: Fri Aug 04, 2017 11:19 am
Location: North Leicestershire
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by geoberni »

This it the crux of the matter... which is really puzzling me...
I have noticed a pattern of it working fine around 14V without headlights on in the day. Then at night when I put headlights on it will stay at 14V for a few minutes and then drop down to 12-point-something volts, and then gradually decrease. If I turn the headlights off and start it up again, I will not get 14V and it will stay the same as it was around 12V or lower depending on how far I have ran it. However the next day, with the headlights off, I will start it up and it will charge and run well at 14V again. I was able to do this on short runs for a good few months.
Something is happening to the Alternator, but it's common to every installation. :-?
I'm sure there's probably something else, that is occurring which you're not noticing, or even being aware of...
It's as if something is overheating and causing the failure, which it then recovers from after a few hours or overnight.
Belt tension perhaps? Causing Alternator bearings to overheat and stiffen?
Is everything else 'standard' about the engine bay and the electrics?
Anything smell strange about the engine bay when it's failed on you?
Is the Alternator particularly hot?
After the conversion, are the belt pulleys aligned correctly. You wouldn't be the first person to not get the fitment quite right.
These are just the random things I'd be considering in your circumstances.

I'm as puzzled as you are...

(even if you've fitted 100/55W Halogens, the alternator should still cope easily with the extra amperage)
Basil the 1955 series II

Image
BenDixon2002
Minor Friendly
Posts: 20
Joined: Sat Feb 22, 2020 7:48 pm
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by BenDixon2002 »

Yes that’s something to think about - the Chinese alternators would fail completely and never recover - this is the only alternator which recovers after a while. Of course I haven’t been able to test the alternator yet to see if it has recovered this time.

Maybe the fan belt tension is too tight like you say, I thought I had it at half an inch slack but I could slacken it off a little bit. Maybe it’s the alignment. Anything else that would make it run hot? It’s only with the lights on though I get problems.

About a month ago I had a bad earth on one of the headlights, so I thought that was causing the problem. I replaced the bullet connectors with ring connectors and securely bolted them to the inner wings where they earthed originally.
User avatar
svenedin
Minor Legend
Posts: 2443
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by svenedin »

BenDixon2002 wrote: Tue Feb 04, 2025 10:39 am Yes that’s something to think about - the Chinese alternators would fail completely and never recover - this is the only alternator which recovers after a while. Of course I haven’t been able to test the alternator yet to see if it has recovered this time.

Maybe the fan belt tension is too tight like you say, I thought I had it at half an inch slack but I could slacken it off a little bit. Maybe it’s the alignment. Anything else that would make it run hot? It’s only with the lights on though I get problems.

About a month ago I had a bad earth on one of the headlights, so I thought that was causing the problem. I replaced the bullet connectors with ring connectors and securely bolted them to the inner wings where they earthed originally.
If the problem only and definitely only occurs with the headlights on then surely there is some issue with those circuits? Does the floor dip switch work properly? Do you use full beam? On the other hand perhaps you always have the headlights on and never just sidelights so it could also be the sidelight circuit.......

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
simmitc
Moderator
Moderator
Posts: 4877
Joined: Thu Apr 15, 2004 9:43 am
Location: Essex
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by simmitc »

A bit "off the wall", but is the dip switch working correctly and changing over rather than adding two filaments together. Even if this was the problem, the alternator should still cope, but just looking for a reason for a high load. As the problem does not occur in daylight, I would check all the wiring for the lights - remember that there is no fuse for the headlights, so a short could be present, not enough to cause a wire to melt, bit enough to draw some power. Some cars had a cluster of three single bullet connectors. If the insulation was failing, then that might be a problem.
User avatar
geoberni
Minor Legend
Posts: 4111
Joined: Fri Aug 04, 2017 11:19 am
Location: North Leicestershire
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by geoberni »

simmitc wrote: Tue Feb 04, 2025 11:01 am A bit "off the wall", but is the dip switch working correctly and changing over rather than adding two filaments together. Even if this was the problem, the alternator should still cope, but just looking for a reason for a high load. As the problem does not occur in daylight, I would check all the wiring for the lights - remember that there is no fuse for the headlights, so a short could be present, not enough to cause a wire to melt, bit enough to draw some power. Some cars had a cluster of three single bullet connectors. If the insulation was failing, then that might be a problem.
Good thought, 'off the wall' is very much what is required in such situations.
I don't think the actual Dip Switch would cause it, but only because I took Basil's apart during Lockdown (Almost 5 years ago, that's scary :o ) to fix it, so I understand how it operates. I assume latter switches are the same concept as Basil's early one. Explanatory Video here is interested: viewtopic.php?p=636467#p636467
But yes a 'partial short' sufficient for excess current drain but not to melt wiring could be a factor in the strange problem....

I do feel the Kwikfit efforts were somewhat 'Level One' in terms of trying to find a fault.
An actual auto electrician with a range of test equipment and electrical knowledge should hopefully find it, although a caveat to that is many these days are only capable of doing what the computer says when it's plugged in....
The Kwikfit attempt sounds very much like simply following a flow chart, rather than an 'engineer' applying their training and knowledge.
Basil the 1955 series II

Image
User avatar
svenedin
Minor Legend
Posts: 2443
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by svenedin »

Perhaps we're narrowing in on target.....Assuming a partial short to do with headlamps it could be anywhere but most likely at a switch or connection somewhere unless there are melted wires lurking in the loom. Thinking about it, a test would be to discover continuity between wires where there should be no continuity i.e a low resistance when it should be open circuit.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
panky
Minor Legend
Posts: 2028
Joined: Wed Aug 20, 2014 4:12 pm
Location: Cheshire
MMOC Member: No

Re: My Car Breaks Alternators! Please help

Post by panky »

It could be something a simple as a bad connection on the alternator. I had a similar experience with a Mini when, on it's first trip out after a restoration, I ended up on the hard shoulder, the first time I'd ever called out the RAC. He got me to a safe place, pulled the plug out of the alternator, a few scrapes with a screwdriver on the terminals and it was fine and never gave any more trouble.
Another little gem I picked up is that if you have an LED fitted to the ignition light the alternator won't charge unless you give it a really good rev, similarly if a normal bulb in the same position is loose or has failed. Hopefully something as simple as that.
Image
simmitc
Moderator
Moderator
Posts: 4877
Joined: Thu Apr 15, 2004 9:43 am
Location: Essex
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by simmitc »

That's a good point, what happens with the ignition warning light. Normal operation: switch on, light comes on. Start engine and rev, light goes out. Don't confuse it with the oil pressure warning lamp. Has a previous owner had the speedo out and fiddled? We have been thinking headlamps as per report, but a charged battery can run the ignition in daylight for quite a long while without any charge having to go in. Against this idea is the "OK when cooled down", but definitely worth checking.
AndyStopford
Newbie
Posts: 3
Joined: Mon Sep 02, 2024 8:14 pm
Location: Kent
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by AndyStopford »

One suggestion, further to the above two posts - there must be a reliable electrical supply to the alternator to properly energise it. If this isn't the case
a)The alternator won't cut in
b)The rectifier diodes will fail sooner or later (which is why you shouldn't run an alternator equipped engine with the battery disconnected)

I wonder whether you have a poor live connection to the alternator, which is good enough when the electrical load is low, but goes high resistance when the headlamp load heats it up, causing the alternator to cut out and eventually fail altogether. I don't know whether the ignition warning light would necessarily come on under these conditions.

It could be worth checking that you have good connectivity with all the alternator connections (the number can vary according to which alternator is fitted), ideally check the resistance between the plug terminals and live terminal on the battery, and that the plug fits tightly onto the alternator terminals.
BenDixon2002
Minor Friendly
Posts: 20
Joined: Sat Feb 22, 2020 7:48 pm
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by BenDixon2002 »

https://www.youtube.com/watch?v=IEylpJ8selc

I recharged my battery and reinstalled it. In this video you can clearly see the problem. First I start the car with the headlights off and the voltage jumps straight up to 14.4V. Then I turn on the lights and it immediately drops down to 12V (not charging). I have experimented and found that this is not affected by high or dipped beam (happens either way). I turn the headlights off and the voltage does not recover to charging levels. I restart the car with the headlights off again and this time it does not recover to charging levels. If I leave the car for a while (a few hours in this case), the alternator will charge again so long as the lights are off. :-?
oliver90owner
Minor Legend
Posts: 1777
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: My Car Breaks Alternators! Please help

Post by oliver90owner »

My suggestion is to check the brush gear as a first action.
simmitc
Moderator
Moderator
Posts: 4877
Joined: Thu Apr 15, 2004 9:43 am
Location: Essex
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by simmitc »

Oliver may well be right for this one alternator, but even if correct, that does not explain why there have been so many failed alternators in such short periods of time - that suggests that there is a problem on the car.
User avatar
Bill_qaz
Minor Legend
Posts: 1002
Joined: Fri Jan 14, 2022 7:31 pm
Location: Oxfordshire
MMOC Member: Yes

Re: My Car Breaks Alternators! Please help

Post by Bill_qaz »

Repeat your test with one headlamp disconnected then swap sides and see if it happens with left only, right only or only with both connected.

You could also try with the cars lights off temporarily connect two head lamp bulbs directly to the battery and see if it creates the same issue
This may help determine if it's a headlamp wiring issue as suggested by others. Or is it just a load issue causing the alternator to stop charging.
Regards Bill
michael4
Minor Friendly
Posts: 48
Joined: Sun Oct 06, 2024 9:32 am
Location: UK
MMOC Member: No

Re: My Car Breaks Alternators! Please help

Post by michael4 »

I assume no relays were fitted with the new headlights? Just asking...
Post Reply