Postive to negative earth

[vibrodolly]

Hello,
I have just Bu88ered up my +ve earth dynamo.
I have sheered off one of the fixings, so the body does not fix to the car anymore.
I suppose I could build up something with washers, but it would only be temporary.

I have decided to go all modern-like and go -ve earth and might fix this http://www.ebay.co.uk/itm/New-Stealth-D ... 5aee5ca2d8

It looks like it will fit the original fittings, so that's good.
What else do I have to convert? How easy is it? What do I do? etc

Thanks

Nick

[andy.pointeer]

Hi
The link is for a Alternator that look and is the same size as a Dynamo, so some wiring changes will be required. An Alternator conversion can be purchase from Bull Motif/ESM for about £60 +vat, about half the cost

To Change to negative Earth look for Technical Tips on the Home page and go to Negative Earth. this show dynamo conversion, so you will not need to do all the steps if adding alternator.

[mogbob]

Nick
There are two sources of Info on the website.
Under the Technical sections Tips, search for Negative Earth.... i.e converting from Positive to negative earth.
On the Forum ...Electrical section , at the top of the page ,look for Alternator.

Because you have chosen a stealth type Alternator, it seems to have the same external physical dimensions as the old dynamo.
In theory therefore, it should bolt straight onto the engine back plate / gearbox housing.

You should get instruction re electrical connections to your new alternator.

If you have extra accessories like an ammeter ,( these are usually only rated to cope with 30amps ), clock, radio etc which are positive earth setups , you will need to alter/ change these.Otherwise it is pretty straight forward.

Is the existing electrical wiring in good health ? So, if you can wield a spanner and car electrics don't freak you out it's worth having a go.

A reconditioned dynamo would be cheaper ( you have to buy outright no doubt, rather than exchange, as the company would claim the old dynamo was unserviceable !! ).As I always say... your car ...your decision.
Bob

[tysonn]

Wow thats not a cheap upgrade!You can just buy a used alternator for a lot less.It has no pulley either.Will yours fit?

[vibrodolly]

Thank you people. It will have to wait 'til round Easter now.
I will let you know

Thanks

Nick

[bmcecosse]

The cost of that thing is eye watering!!! Just fit another dynamo.... Or search for a more realistically priced alternator. The bracket to fit a 'normal' alternator is not hard to find.... http://www.ebay.co.uk/itm/18-ACR-45-Amp ... 27cc7bb3bf This is a much better buy....... Or take a chance on this one....which is more in my price range (but expensive postage..) http://www.ebay.co.uk/itm/Morris-Minor- ... 4d1a598b9b and here's the bracket...... http://www.ebay.co.uk/itm/Classic-Mini- ... 4ad2450a4d

[alexmcguffie]

Hi Nick,

If your Minor is a second car for weekends etc, stick with a dynamo, easily up to the job still. If you use it everyday then an alternator would give you more peace of mind driving in the dark winters night.

[bmcecosse]

Absolutely -ask on here in the 'wanted' section or this one 'for parts' on ebay..... http://www.ebay.co.uk/itm/Classic-Briti ... 3f325d4056 Didn't realise the price these fetch! I gave a perfectly good one away last year - but it was for a 'good cause'.....
What is broken on your dynamo - can it not be repaired?

[vibrodolly]

The broken bit is one of the fixing holes, one of the two that act as the pivot for adjusting.

I have decided to do the upgrade, but with the ESM one. While the car isn't every day, it is a standby as well as fairly regular use. Winter and summer. Town runs with lots of electrics on runs the battery down sometimes.

Thanks for the help

[aupickup]

my minor used to be an everyday car summer and winter short and long journeys
wipers on, halogens on heater on and never had a problem with a dynamo keeping up and allways started

[bmcecosse]

Certainly with a dynamo - if you are on 'town runs' you can't afford to have the headlights on all the time.... and use wipers only when moving, and foot off the brake when stopped (which is good manners anyway to the chap behind...). To an extent - an alternator removes the need to manage the current use quite so carefully. A dynamo easily copes on a car doing good runs each day. If the car sits unused for days on end - consider a solar charger to keep the battery topped up when the car is not in use.

[vibrodolly]

Thank you for suggestions.
The new alternator arrived today. (the cheaper one!)

Trouble is, I just don't understand wiring diagrams.
The technical tips are most useful and I can understand them from this forum.

A question... Do you still need the charging box? Are there are leads to re/ disconnect here?

Some suggest there will be redundant wires that need taping up. Are there any as far as people here can tell?

Thank you again

Nick

[mogbob]

Nick
Print off the instructions I suggested in my post of Sunday the 23rd March.

i.e. Tech Section ( from home page ) Negative Earth
Electrical Section of the Forum top of page " Alternator Wiring Diagram

Did you get a wiring diagram with the new Alternator, any cable /wiring / connector, etc.

Pour yourself a drink and have a quiet read of everything you have.Some of the Negative Earth conversion instructions will be " Not Applicable " because you are substituting the Dynamo for a new Alternator.

Answers.
Most people leave the Control Box in situ , to act as a junction box for the wires, it keeps it tidy.
Yes.... there will be redundant wires.( see diagram in the instructions ).
Stating the obvious.... you will need to disconnect the battery whilst removing the dynamo bits / installing the Alternator.

Having read everything can you report back with information as to what "exactly " came with the new Alternator.A complete list would be useful.For instance.... did it include a new mounting bracket for the Alternator.That way ,if you need to purchase more wires, connectors, etc . , before you start, we can advise.
What Electrical tools do you have to hand ?

What part of the country are you in ( don't post your full address on line !! ) the nearest large Town will do ? Have you been along to a local Group meeting yet, there is usually a friendly Member willing to lend a hand.

Bob

[andy.pointeer]

I purchased my alternator conversion from ESM and it came with all the brackets and a wiring loom with plug for alternator. From memory there were no bolts. There was also an instruction sheet and this was very easy to follow and I left control box in place.
You need to do the negative convertion to coil etc first

Instruction sheet below


[frame][/frame]

Hope this helps

[bmcecosse]

Yes - it's all very straightforward - and hopefully no 'spare' wires - it can be connected up with the existing wires. Easiest to leave the control box in place...but it is doing nothing. You probably need a shorter fan belt (usually 825) - did it come with one? Good idea to fit a new one anyway - and get a spare the same length. Take great care to check the pulleys are all dead in line...often a thin washer has to be fitted between water pump and alternator bracket to get them spot on.......

[vibrodolly]

Hello again.

I've done what I think is correct, but it wont go

Physically fitted as described. Alternator fitted and fettled.

I turned the battery round and reconnected.
I reversed the coil wires, though the coil is currently dangling until the engine goes, whereupon I will fix it to the wing.

There were 3 wires to the old dynamo, yellow - yellow and black - yellow and green. I have a feeling the yellow s were once a brown colour.
These have all been disconnected from the charging box at F and D. Nothing else has been disconnected.

The new thick and thin brown wires have been connected to the solenoid (they were joined already), the connection furthest from the battery that had the rubber covering originally.

I can't work out where to connect the remaining thin brown wire that has a spade on it. This goes to the warning light, but surely the engine would go without the warning light connected?

Nothing else has been changed or moved. The starter motor, solenoid etc has all the wires in the original position.
Yes the engine turns over. It's gone dark now so I haven't checked for a spark, but it went before I started attaching the alternator. All other lights and electrics work.

Any help much appreciated as usual.
Thanks
Nick

[bmcecosse]

The browns need to be on the solenoid live connection.....the one directly connected to the battery +ve......NOT the furthest away one...which is presumably connected to the starter....... The coil body really should be earthed. Fuel pump points will also need cleaning as reversing the polarity reverses the years old 'pit and pimple' on the points....

[vibrodolly]

Thank you bmcecosse, I'll let you know, but it will be next weekend now.

Nick

[alexmcguffie]

Hi Nick,

Firstly, you do need the ignition light connected and working for an alternator to generate charge. This creates a small magnetic field in the alternator to kick things into life.

1) You should have had 2 wires on terminal D on the regulator (either yellow or brown/yellow depending on year). One of these goes to the ignition light, the other to the alternator/dynamo. These 2 wires still need to be connected together although not to the regulator. Then the loose wire you should have at the alternator end (yellow or grown/yellow again) needs connecting to the smallest of the 3 terminals on the alternator.

That should get you charging at least.

2) As for not starting, I'm not sure about having to swap the wires on the ignition coil - its a while since I've done a polarity conversion but don't remember needing to do that. You wouldn't do any harm by swapping the 2 wires back over and giving it a try.

Alex

[andy.pointeer]

As bmcecosse has indicated the new thick and thin brown wire is connected on the terminal on the solenoid with the original thick brown wire and the very thick black that goes to the battery

[frame][/frame]

On the instruction sheet provided above, it is states a yellow wire, on my conversion its brown and and has a male terminal that is connected to the original thin brown/yellow taken off from terminal D of the control box.
I did not connect together any of the other wires removed, just taped them in a bundle[frame][/frame]