This guide is reproduced by kind permission of Peter Kay from the Yahoo Senator Forum.
Thanks to Tetleysmooth for getting permission.
The aim here is to overcome hot starting problems on the 3.0 carlton and senator models through the addition of a relay to the starter circuit.
The relay modification is very straightforward and cheap.
Items required from Maplin:-
One 12Volt, 40A, Single pole, Normally Open Automotive Relay
Order Number AR 32K Cost £5.29 inc VAT
1 Metre of Twin Power Cable (Standard two core figure of eight) 3.53mm² CS Area
Order Number XS74R Cost £1.29. Before use this is split into two seperate 25Amp leads, one black, one red, for use as required.
One pack of suitable terminal connections for the relay:-
Fully Insulated Crimp Terminal, 6.35mm (1/4 inch receptacle, Blue)
Order Number JH82D Cost £0.95 inc VAT per pack of 10
If the car is fitted with cruise control you will also need:
1 Resistor 22 Ohm, 10W, High Power, Wirewound.
Order Number H22R Cost £0.25 Incuding VAT
Procedure.For safety, first disconnect the battery Negative terminal, then Positive. Identify the small terminal on the solenoid of the Starter Motor Assembly, which carries brown feed wire from ignition switch. Remove this lead from the terminal on the solenoid. (This lead will eventually be connected to the coil terminal (86) of the new relay, to operate it in place of the solenoid.)
Find a suitable location for the relay. On the 12V engine there is a suitable screw which secures an engine cover plate, on the rear end of the engine block, adjacent to the starter.
On the 24V C30SE engine however, access is far more difficult due to the exhaust manifold obstructing the area, and I am not sure if this cover is still present. First try to find a location close to the starter where a self-tapping screw can be fitted to secure the relay mounting tab, or an existing screw can be utilised. This mounting screw can also be used to provide a chassis connection for one side of the relay coil (Terminal 85), so it is best to ensure that the point chosen is a good earthing point.
As an alternative, the relay can be secured to the top of the solenoid using large 'tie wraps', but with this option a longer earth lead must be connected from the relay coil (Terminal 85) to the chassis, possibly to the nearside wing or bulkhead. The relay can also be located in a remote location from the starter, but this means that the original solenoid energising connection wire must be extended to reach.
Wire up the relay as illustrated.
Unfortunately, the circuit as shown may cause the cruise control relay to stick in the engaged position. This is because the chassis return circuit for this relay is connected to the solenoid feed wire, ensuring that when 12V is applied to this wire during starting, the relay will always drop out. When the 12V is removed, it would normally be grounded via the solenoid coil which has a very low resistance. The new relay coil connected to this wire has a resistance of about 70 Ohm, which is too high to provide an earth for the cruise control relay in some circumstances. To provide a low resistance, it is sometimes necessary to wire a resistor in parallel with the coilof the new relay. To prevent problems, solder the specified 22 Ohm high wattage resistor between the bottom of terminals 85 and 86 of the new relay before fitting it. Ensure it's leads are insulated with suitable sleeve and that connection to these terminals, using the detailed crimp connectors, is not compromised. Alternatively, the resistor ends can be crimped, with the wire, into the associated terminal connectors.
DISCLAIMER: This guide was last updated in October 2005 and, as such, prices may not be correct.
As I have simply copied this verbatim from a PDF file, Myself or totalcarlton cannot be held responsible for any inaccuracies in this procedure.
