Loose wire from starter and alternator query

[Ant]

I have noticed a disconnected wire, which appears that it should be connected to the starter, it's a black rather than red and goes on one of the spade ends.

The strange thing is that the car starts, the starter fires, so I wonder what will happen if I reconnect it

[Ben Lessani]

Just looks like the -ve for the starter solenoid.

But odds are the solenoid is grounding through the starter > gearbox > chassis > battery.

[Ant]

Yeah, that's sort of what I figured, well about to (probably) swap out the alternator, so will connect it up and make sure there's not problems, I just hate having loose wires in the bay, but at least it's not live.

[Ben Lessani]

Yeah, that's sort of what I figured, well about to (probably) swap out the alternator, so will connect it up and make sure there's not problems, I just hate having loose wires in the bay, but at least it's not live.

Test it with a multimeter to be sure

[Ant]

Test it with a multimeter to be sure

Good point, IIRC that would be a voltage check (once battery is reconnected), and if that's good I should be able to check a resistance between it and casing.

Now got the worn alternator out (left), but noticed a difference between it and my replacement (right) (of my old engine)

There's a rectangular block on the worn one (bottom right) I think this could be the regulator diode? but it's not on my replacement, do I need to transfer them over, what will happen if I don't (or do and I don't need it)?


Edit Can that, the diode's connected to the brushes, so leads to the question what is it and do I need it?

[rubjonny]

pic 1:
thats the wiring for the cold throttle enrichment and cold start valve. goes to the pin marked 15a on the starter.

Pic2: yeah you need to transfer that over, iirc its a suppressor?  Only 1 screw to change it over so you might as well eh

[Ant]

pic 1:
thats the wiring for the cold throttle enrichment and cold start valve. goes to the pin marked 15a on the starter.

Didn't realise there was wiring for that down on the start as well. Might explain my poor running over last winter, strange how two garages with a remit of 'it keeps cutting out when it's cold' never found it (assuming it was off then)

Pic2: yeah you need to transfer that over, iirc its a suppressor?  Only 1 screw to change it over so you might as well eh

1 very, very persistent screw, what damage could I do if I don't change it over, got a big trip up to Derby tomorrow, and a little busy between no and then.

[rubjonny]

1. once its running it probably wont cause those symptomes, will just make it run a bit bad. if its cutting out have a look at the over-run cutoff valve behind the airbox, the big plastic thing. minme kept dieing on me when putting the clutch in and it was down to this thing, swapped on another one and all was well.

2. not 100% sure exactly what it does, could be a voltage regulator in which case it might over-charge the battery which would be bad!  Hopefully someone who knows better will chime in on that one

[Ant]

1. once its running it probably wont cause those symptomes, will just make it run a bit bad. if its cutting out have a look at the over-run cutoff valve behind the airbox, the big plastic thing. minme kept dieing on me when putting the clutch in and it was down to this thing, swapped on another one and all was well.

Will have to see how it runs once winter comes.

2. not 100% sure exactly what it does, could be a voltage regulator in which case it might over-charge the battery which would be bad!  Hopefully someone who knows better will chime in on that one

I originally thought it was the voltage regulator as well, but according to my Bentley service manual that's combined in with the brushes.
Of course realising that the old alternator was a Bosch and the new once a Lucas, might be differences, but the Lucas has everything in place for this to be fitted. Will go check what voltage it's putting out.
Fortunately (for the car, unfortunately for me) my interview tomorrow has been postponed, so I have most of tomorrow to drill out the screw and get a replacement sorted (assuming that the wd40 doesn't do the job for me)

[l333]

hi your little black box is a supressor and the reason its there is to stop electrical interferance ie radio noise