Author Topic: wires on twin cam special near carburetors  (Read 155 times)

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Offline analogmike

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wires on twin cam special near carburetors
« on: Saturday,May 31, 2025, 01:07:26 PM »
1974 Twin Cam Special US spec

Does anyone know where these wires go? I pulled my carburetors off to get them rebuilt and trying to clean up things below it.   I searched all the manuals and wiring harness diagrams but could not figure this out. 

the first picture is a device on the carburetor side of the engine bay just below the emissions plaque. The brown wire which appears to be a hot wire connected to the starter is not connected. I just don’t know what this device is, or if I should reconnect the brown wire.

The second picture shows two yellow wires (circled) coming out along the suspension arm, one of them goes back and into the harness by the right rear tail light. The other yellow wire seems to have been chopped off so I’m not sure where that second one goes or what it does

The third picture is the coil and there’s another yellow wire with a large connector on it that is not connected.

any help is appreciated!

Regards, mike

'73 911RS, '08 911 GT3 cup, '01 Viper GTS, '74 Lotus Europa Special, '70 Lancia Fulvia 1600HF, '15 Audi S3, '04 TowRig

Offline 4129R

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Re: wires on twin cam special near carburetors
« Reply #1 on: Saturday,May 31, 2025, 11:41:19 PM »
There is a wire which goes from the starter solenoid to the coil, which gives 12v to a 9v coil,  only on starting. If you have a 9v coil, the + side of the coil is attached to a wiring going to a wire wound resister on a white ceramic body close to the coil, which reduces 12v ignition to 9v when the engine has started. I believe the wire from the starter solenoid to the coil is white with a red trace.

The relay is not standard Lotus wiring that I have ever seen on any TC or TCS.

Offline analogmike

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Re: wires on twin cam special near carburetors
« Reply #2 on: Sunday,June 01, 2025, 03:39:00 PM »
There is a wire which goes from the starter solenoid to the coil, which gives 12v to a 9v coil,  only on starting. If you have a 9v coil, the + side of the coil is attached to a wiring going to a wire wound resister on a white ceramic body close to the coil, which reduces 12v ignition to 9v when the engine has started. I believe the wire from the starter solenoid to the coil is white with a red trace.

The relay is not standard Lotus wiring that I have ever seen on any TC or TCS.

very interesting, I will check that out. It does seem like that’s a problem I have, it’s sometimes very hard to start the car, it doesn’t want to start until I turn the key back to run position in then it might fire up.
Regards, mike

'73 911RS, '08 911 GT3 cup, '01 Viper GTS, '74 Lotus Europa Special, '70 Lancia Fulvia 1600HF, '15 Audi S3, '04 TowRig