Wiring harness issue

Austin Healer

Austin Healer

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Autosparks UK is ultimate the source for Tiger wiring harnesses, stock ones, anyway. I bought a Mk1 harness from Sunbeam Specialties. I don't know his supplier, but the harness came labeled with Autosparks part number.

The harness is incorrectly made. There are 2 brown wires routed to the solenoid attached to the main battery cable. The large gauge wire goes to the voltage regulator, the smaller gauge wire is supposed to go to terminal #1 on the fuse box. This is the supply for the horns and map light. The harness I rec'd has the smaller gauge wire supplying voltage to the headlight switch.

The regulator "B" terminal should have three brown wires. One for the ignition switch feed, one for the light switch and the large gauge wire which connects to the solenoid. The manufacturer has reversed the wires for the fuse box term. #1 and the headlights.

For normal operation this is not an issue. If you have an ammeter it is. That's because the headlight circuit is now on the "wrong side" of the ammeter and the current draw of the headlamps will not be reflected in the operation of the gauge.

Normal installation of an ammeter in the MK1/MK1a requires that the lead from the solenoid to the be interrupted and the ammeter wired in series... solenoid to one pole of the ammeter, the other pole of the ammeter goes to the regulator. This is plainly illustrated in the factory wiring diagram. If the wiring harness in your Mk1/MK1a is like mine you will also have to combine the 2nd brown wire (headlights) with the wire to the ammeter. that way the headlight circuit will be on the correct side of the ammeter and their use will be reflected in the gauge operation.
 
Austin Healer said:
Autosparks UK is ultimate the source for Tiger wiring harnesses, stock ones, anyway. I bought a Mk1 harness from Sunbeam Specialties. I don't know his supplier, but the harness came labeled with Autosparks part number.

The harness is incorrectly made. There are 2 brown wires routed to the solenoid attached to the main battery cable. The large gauge wire goes to the voltage regulator, the smaller gauge wire is supposed to go to terminal #1 on the fuse box. This is the supply for the horns and map light. The harness I rec'd has the smaller gauge wire supplying voltage to the headlight switch.

The regulator "B" terminal should have three brown wires. One for the ignition switch feed, one for the light switch and the large gauge wire which connects to the solenoid. The manufacturer has reversed the wires for the fuse box term. #1 and the headlights.

For normal operation this is not an issue. If you have an ammeter it is. That's because the headlight circuit is now on the "wrong side" of the ammeter and the current draw of the headlamps will not be reflected in the operation of the gauge.

Normal installation of an ammeter in the MK1/MK1a requires that the lead from the solenoid to the be interrupted and the ammeter wired in series... solenoid to one pole of the ammeter, the other pole of the ammeter goes to the regulator. This is plainly illustrated in the factory wiring diagram. If the wiring harness in your Mk1/MK1a is like mine you will also have to combine the 2nd brown wire (headlights) with the wire to the ammeter. that way the headlight circuit will be on the correct side of the ammeter and their use will be reflected in the gauge operation.
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YUP: I have another UK harness that I am reworking because of nasty flaws. Are they hiring rejects over there? This one came with a Lucas Alt plug on the dynamo end for a Tiger MK1A. Try and feed that critter thru the firewall grommet! The regulator ends were all bundled crimped together. It's gonna take some head scratching . . . . . .
 
I have one here just like that! I figured it must have been a special order as it came with the car... no provision for a regulator at all and a Lucas Alt. plug... It also has wiring for a cooling fan circuit. Going to have to ask the customer about it!
 
Austin Healer said:
I have one here just like that! I figured it must have been a special order as it came with the car... no provision for a regulator at all and a Lucas Alt. plug... It also has wiring for a cooling fan circuit. Going to have to ask the customer about it!
Click to expand...
I worked the Lucas plug off and did a direct wire to a one-wire Alt. Now to figure out the ign warning light circuit using the plug's field wire. Keeps my noggin busy.
 
my understanding is that it is not possible to make an ignition lamp work with a one wire alternator.... if you figure out how, I'd love to hear about it!
 
I bought a harness from a company with British in its name - never again.............................
 
I converted to an alternator system 20 some years ago - B382 series Tiger. 1965 style Ford alternator with a small one wire voltage regulators mounted to the alternator.
1717941402709.png
1717942007905.png

I made the original generator voltage regulator into a junction box to clean up the wiring.
Orange wire on new alternator voltage regulator to NG wire to junction box Field connection with NY wire to ignition warning light - ignition light works correctly.
Ron Fraser
 
Hoghead said:
I bought a harness from a company with British in its name - never again.............................
Click to expand...
interesting.. I've never had a problem prior to the harness I described and I wouldn't have noticed there was any issue with it at all if I hadn't installed an ammeter. Electrically it was fully functional. The harness from the same source for my MK2 is completely accurate.

The oddball harness like Randy Willet's I can't explain. I still have to contact the owner of the car and find out if he had it specially constructed.
 
0neoffive said:
I worked the Lucas plug off and did a direct wire to a one-wire Alt. Now to figure out the ign warning light circuit using the plug's field wire. Keeps my noggin busy.
Click to expand...
Out of curiosity... was the bag that harness was in labeled WILKINSON 1582 SP Made in England?? I have no idea who actually manufactured it, but I'm wondering. The one I have also has an electric cooling fan circuit added to it.
 
Austin Healer said:
Out of curiosity... was the bag that harness was in labeled WILKINSON 1582 SP Made in England?? I have no idea who actually manufactured it, but I'm wondering. The one I have also has an electric cooling fan circuit added to it.
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The bag was sealed with no markings on it. It sat with the project waiting for years so I can't speak to your question. It was ordered as and for a stock MK1A. As for the ign pilot, I'm thinking along the lines of a make/break circuit that allows a resistor grounding in a static state and trips to opposing voltage as the Alt spins up. I've got a Bro who was a circuit trouble shooter for NASA for decades. Maybe I can dump the issue in his retired lap (lol).
 
rfraser said:
I converted to an alternator system 20 some years ago - B382 series Tiger. 1965 style Ford alternator with a small one wire voltage regulators mounted to the alternator.
View attachment 19518 View attachment 19519
I made the original generator voltage regulator into a junction box to clean up the wiring.
Orange wire on new alternator voltage regulator to NG wire to junction box Field connection with NY wire to ignition warning light - ignition light works correctly.
Ron Fraser
Click to expand...
Excellent! Where did the little box come from ? Source? Part numbers, etc.?
 
NPD 10A316 Conversion Kit, One wire alternator
I'm sure other Ford part catalogs carry similar part.
 
0neoffive said:
I worked the Lucas plug off and did a direct wire to a one-wire Alt. Now to figure out the ign warning light circuit using the plug's field wire. Keeps my noggin busy.
Click to expand...
There's a part that is supposed to work with 1 wire alternators to connect and operate the ignition warning light. I haven't r\tried it yet as my car is not back from the restoration shop.

https://americanautowire.com/produc...os=1&_psq=charging+warning+light&_ss=e&_v=1.0

I intend to install a 1 wire alternator and purchased a Mark1A harness from Autosparks in the UK. It has the upgrade wiring for an alternator, but unfortunately, it's made to use a Lucas alternator and has that plug on it. British Wiring in Pennsylvania sells the Autosparks harness. There will definitely be some rewiring of the harness involved. I also plan on installing a voltmeter.
 
fjohn49 said:
There's a part that is supposed to work with 1 wire alternators to connect and operate the ignition warning light. I haven't r\tried it yet as my car is not back from the restoration shop.

https://americanautowire.com/produc...os=1&_psq=charging+warning+light&_ss=e&_v=1.0

I intend to install a 1 wire alternator and purchased a Mark1A harness from Autosparks in the UK. It has the upgrade wiring for an alternator, but unfortunately, it's made to use a Lucas alternator and has that plug on it. British Wiring in Pennsylvania sells the Autosparks harness. There will definitely be some rewiring of the harness involved. I also plan on installing a voltmeter.
Click to expand...
yes,

pretty much what I have found... pretty silly, as installing a one wire alternator just requires a wire from the alternator to either the battery or the terminal on the solenoid. Hardly worth screwing up a perfectly good wiring harness for... It would seem that everyone has to overthink how to do it!
 
Austin Healer said:
yes,

pretty much what I have found... pretty silly, as installing a one wire alternator just requires a wire from the alternator to either the battery or the terminal on the solenoid. Hardly worth screwing up a perfectly good wiring harness for... It would seem that everyone has to overthink how to do it!
Click to expand...
I have several Lucas Alts from TR 7 projects and the issue has always been trying to mount them. No convenient bracket works with them on the Ford baby 8 and then there's getting it lined up with the pulleys?
 
I have seen several pictures where they mounted the alternator on the Generator bracket.
This looks like a very interesting install, but I have seen no description. Lining up the pulleys is the critical part.
Long bolt and several spacers are needed, and my guess is that different alternators will require different spacers.

1718135893588.jpeg
 
rfraser said:
I have seen several pictures where they mounted the alternator on the Generator bracket.
This looks like a very interesting install, but I have seen no description. Lining up the pulleys is the critical part.
Long bolt and several spacers are needed, and my guess is that different alternators will require different spacers.

View attachment 19522
Click to expand...
I messed with that for a while and determined the fat Lucas Alt required trimming the heck out of the stock dyno bracket in order to achieve some adjustment swing & clearance. It would make for a good project for our Thai R & D fellow.
 
0neoffive said:
Got one of those brackets that will fit the fat Lucas Alt ??
Click to expand...
Thai R&D guy here - no idea as it is designed for a mini Denso mount with the Powermaster models known to fit listed on the link I provided.
I doubt the Prince's alternator is the same as a skinny Desno
 
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