Like many other parts on my Fastback, it turns out that the alternator stator has been competently (stress, competently) bodged by someone lacking either cash or access to correct parts (see pictures).
The wires parted while I was investigating the tape used to wrap them, but the alternator was working fine before the strip down. Being (a) "economical" and (b) stubborn I intend to have a go at salvaging the wiring.
But my medium-term aim is next year's international rally and I'm not sure that I want to rely this item far from home.
So, I'm seeking up-to-date views on the various two-wire stator options available, plus any arguments as to why going to a three-wire version might be worth the trouble.
I don't see a problem here, obviously replace the wiring going through the cover and up to the regulator but just use a couple of in-line crimps to connect to the existing wiring. Sleeve with heat shrink.
The 'bodge' is to stabilise the wiring going into the alternator itself as it goes brittle with age and heat.
If it worked before, keep it.
If you do want to replace then stick with a two wire (single phase) version rather than a 3 wire (three phase) version as this would involve changing wiring and regulator. Three phase does not give you a great deal more power, just tends to start at slightly lower revs.
Al Oz is going to start shouting at somebody soon and pointing out that just because an alternator has 3 wires does not necessarily mean it is a 3 phase type. The original Norton fitment of RM 15 and RM 19 Alternators were all single phase but had 3 output wires.
Very correct Phil, Back in the late 50s and into the middle/late 60s we had a lot of 3 wire alternators, in fact ALL 6 V alternators in those days had 3 wires and they controlled the battery over/undercharging with the PRS8 switch and similar switches. 3 phase will give more power at town speeds than single phase, might be worth it. There is a lot of high output single phase units available these days as well on the market. 3 phase is assured by there being 9 pole pieces in the stator. The 6 magnet rotor is the same across all alternators. The 3 wires on Lucas alternators from the late 50s has always been WHITE/GREEN-common, GREEN/BLACK-low output, and GREEN/YELLOW-high output (the high and low output being significant for 6V working. If you want such a unit for 12V then GRN/BLK and GRN/YLW are connected together, but we all know that!) IF of course you do have a 9 pole 3 phase unit then you have the same three colours but the 3 phases are identical so the wiring colours are purely down to Lucas having the worlds supply of WHITE/GREEN, and GREEN/BLACK and GREEN/Yellow wires!
PS I can repair the alternator 'bodge' as above properly.
Tony has suggested an answer to what was going to be my next question, namely "crimping vs soldering".
Crimping would be simpler for me, since soldering means that I'll have to go and buy a soldering iron and revive my very rusty and never very good soldering skills.
Likewise, Tony has answered a related question, namely how to protect the new joints, given the hot oily environment of a standard chain case. Possible alternatives would seem to be self-amalgamating tape, or the paint-on liquid rubber solution that one can get.
How about buying and fitting a belt drive conversion??? No joint contamination issues from then on.
… I think it's wiser to sort out existing problems before taking on another project.
I seem to remember heat-shrink tubing going very soft and failing in the hot and oily chaincase.
… a very helpful (and reasonably priced) repair by Al Osborn.
I was not suggesting that three wire was three phase. Just that if you were CHANGING from two wire to three wire then the only reason would be to go to three phase.
as with any material you use, it pays to research the properties of the material. There are a number that are resistant to oil and heat. But also a number that are not.
I'm in a similar position to Julian, but rather than just one sick stator, I have several. Two are of the open winding type and one 'encapsulated'. What they have in common is that they all failed at the wires-to- stator interface. Is it worth trying to mend them via Al Os (if he's willing) or should I just splash out on a new one? The encapsulated on will need a bit of 'digging' to find the soldering points. I have three Nortons all 6 volt and I seem to be buying stators every couple of years.
Hi again. I seem to be replying to myself. I put it down to old age! I've spoken to a few 'bikey' people and the advice is buy a new stator. So that is what I shall do.
… is for sending your stator collection to Al O. for testing and repair; very reasonable rates and excellent work.
Thanks for positive response Julian, Open wire alternators are a lot easier to repair (just new cables to the outside) than encapsulated but we can still 'have a go' no charge if it can't be done.(no pun intended) A lot of people are still trying to test alternator output by measuring the Voltage-not much point as there is no indication of any Amps/power available and a short to earth wouldn't show up on a voltage test but such a short would kill the output. The proper test is on my web site and is done with a head lamp bulb. aoservices.co.uk