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Running without the alternator wired up
RichardK - 4/9/07 at 09:18 PM

Got most of the plumbing done and would like to have a try at setting up my carb, but seem to remember somewhere saying thats it a no no to run the alt without it being connected, so I thought I could wire it up temporily if I was told what goes where, standard sierra alt or just get one of those emergency fan belts and cut it down so it misses the alt but still drives the water pump.

Is it still a no no?

Any other suggestions so I can run my engine for a bit longer, also heard soething about running in a new cam at 2k revs for 20 mins, so defo need the coolent in.

I'll just wait then for my core plugs to fall out cos I didn't know they needed to be glued in But they might be ok

As always comments welcome.

Cheers

Rich


owelly - 4/9/07 at 09:40 PM

Running without the alternator wired up will be fine. If there is no juice getting to the excitation, then your alternator is just a bundle of spinning bits and cannot hurt anything! But your engine will run out of sparks when the battery is flat!!


daviep - 4/9/07 at 09:49 PM

If it is a Lucas alternator with a plug which looks like this
Lucas plud
Lucas plud

Then it's pretty simple. The small terminal (IND) should be connected to battery positive through a bulb.

Either of the big terminals should be connected to battery +ve using a reasonably heavy piece of cable.

The Alternator body must be connected to earth.

To test your wiring: remove the small wire (IND) and touch it to the alternator casing. The bulb should light, this proves your warning lamp is wired correctly and that the alternator is earthed.

Remember to disconnect the wiring or the battery when you are finished as the circuit is not switched or fused.

Regards
Davie


DarrenW - 4/9/07 at 10:33 PM

Core plugs - i thought if fit tolerance is OK then no sealant required. Most people recommend sealant when retro fitting later etc As you say you may not need. You havent lived until youve had one fail

Ref alternator - id wait until wired up etc correctly. Nowt like knowing all is well for piece of mind.


britishtrident - 5/9/07 at 07:34 AM

Never run without the alternator properly wired up.

Contrary to what has already been posted there can be enough residual magnetism in the stator to provide excitation.


02GF74 - 5/9/07 at 08:41 AM

quote:
Originally posted by britishtrident
Never run without the alternator properly wired up.

Contrary to what has already been posted there can be enough residual magnetism in the stator to provide excitation.


see my post yesterday about this.

according to green bible either run fully wired or fully disconnected. (I did wonder about the residual magnetism bit)


craig1410 - 5/9/07 at 12:26 PM

I've never had a problem running with the Alternator completely disconnected - I think it i s very unlikely to cause any damage.

When you do wire it up, make sure that the wire between the large terminals and the battery are rated higher than the maximum output of the alternator. I used two seperate wires of 30A each from Alternator (45A max) to battery rather than one large wire. I connected one spade terminal to each of the large connectors and then ran this to a single bolt-through terminal on the starter solenoid. Easy.

Cheers,
Craig.


Peteff - 5/9/07 at 01:26 PM

I used the original 2 wires as they are easier to bend than a thick single wire and as said if completely disconnected it should be no problem.


robbydee - 18/11/07 at 06:40 PM

quote:
Originally posted by daviep
If it is a Lucas alternator with a plug which looks like this
Lucas plud
Lucas plud

Then it's pretty simple. The small terminal (IND) should be connected to battery positive through a bulb.

Either of the big terminals should be connected to battery +ve using a reasonably heavy piece of cable.

The Alternator body must be connected to earth.

To test your wiring: remove the small wire (IND) and touch it to the alternator casing. The bulb should light, this proves your warning lamp is wired correctly and that the alternator is earthed.

Remember to disconnect the wiring or the battery when you are finished as the circuit is not switched or fused.

Regards
Davie



Sould i run a seperate wire from the alternator mounting bolts to the chasis?


Macbeast - 18/11/07 at 08:06 PM

Normally alternator body is bolted to the engine block and thus earthed through it. Engine block should then have a heavy braided cable to chassis and thence to battery negative.

To be 100% sure run braided cable from battery negative to engine block preferably at the starter mounting bolt.