Alternator failure, Lucas ACR style, replacement needed tomorrow near London?

[Giant]

Our alternator has failed. No markings on it. Design looks like a Lucas ACR but the back cover doesn't exactly match any of the variants of that I'm seeing online.

 

We very badly need to be back underway on Thursday with a working alternator, so I want to find a drop-in replacement for this by the end of tomorrow.

 

We're tied up at Gravesend. There is a Euro Car Parts here but they don't seem to deal in anything that old. I can travel tomorrow to anywhere in or near London to pick one up.

 

Next day delivery could work in theory (we have an address nearby), but has been very unreliable lately so would want to be very sure the supplier could get it done.

 

Any ideas?

 

Photos:

 

Symptoms:

Was working fine when we left, 13.8V at idle and 14.4V with some revs on.

At some point I noticed the battery voltage dropping, went below and found the alternator light on despite plenty of revs.

Battery and field coil connections are fine.

There's about 2.3V between negative and the field coil terminal regardless of revs (rest of the battery voltage is dropped in the bulb).

The belt had got a bit loose so suspected that, but have now tightened it and no improvement. No squeaking.

 

Diagnosis:

My understanding is that this means either the brushes or some of the diodes have gone. Fixable but given time constraints we want to just swap it out.

 

Installation:

16" pulley on the front of a JP3 driving a 2.5" pulley on the alternator, so ~7700rpm at full revs (1200rpm engine). V-belt with "A" section. Turns clockwise looking from the pulley end.

Edited September 8, 2020 by Giant

[BEngo]

I think an A127 should be a drop in replacement.  You will need to google the leftright handed definition and then there are loads on the web.  You will also need a push on connection version, not the stud connection ones.  That will mean a lower max output.

My last one was bought on line and came overnight from an outfit in Preston Lancs.  About £60 IIRC. 

 

If you want to try Halfords or ECP they fit a Mk1 Escort, again IIRC.

 

N

[TheBiscuits]

9 minutes ago, BEngo said:

My last one was bought on line and came overnight from an outfit in Preston Lancs. 

 

Quite likely to have been LRE, who supply RCR amongst many others.

 

https://www.lancashirerotatingelectricsltd.co.uk/

 

[GUMPY]

Possibly a bit far away on the opposite side of London but

http://www.sahibs.com

Will be able to fix it for you, they have done stuff for me whilst I waited.

Its a good old style company.

Edited September 8, 2020 by Loddon

[Giant]

Thanks for the leads. Have found a similar specialist in Bexley so I'm pulling it out and taking it over there this afternoon.

[pearley]

2 hours ago, BEngo said:

 

If you want to try Halfords or ECP they fit a Mk1 Escort, again IIRC.

 

N

Mk 1 Escorts left the factory with dynamos. 

[Giant]

Success - have now traded in the failed one for a shiny new A127.

[Steve56]

5 minutes ago, Giant said:

Success - have now traded in the failed one for a shiny new A127.

Make sure the replacement comes with a pulley as they are not interchangeable.

[Giant]

3 minutes ago, Steve56 said:

Make sure the replacement comes with a pulley as they are not interchangeable.

Yes, the guy fitted it up to match the one I brought in so should be all good to go.