steve redway

Today I have pinned down where the fault might be. Both the oil pressure switch and ignition circuitry are devoid of their +ve power. This is normally fed from the ignition switch in the run position. Also on this circuit is the heater blower and seat belt dash light, both of which work and illuminate correctly. Therefore it is possible that the 12v common point as I have highlighted in the attached drawing has failed. If it is the commoning of 6 white wires of which 2 of them (the ignition and oil switch) are open circuit. Which leaves a number of questions: Where is this 12v white

Can anyone advise me of the correct wiring to the TR8 V8 oil pressure switch that runs the petrol pump as well as the low oil pressure light on the V8. There are 3 tags to the switch which has an internal change over switch and three wires, a white, a white.red and a white/brown. Not sure which way round they go. Also looking for a TR8 wirng diagram. Thnaks in anticipation.

Thank you for your input guys. Just to clarify. There are just two wires going to the coil, distributor and Holley choke at the front of the vehicle. A white and a White/black. The distributor is in parallel with the coil and incoming pair and a single wire feeds the Holley choke which must have 12v on it to operate. There is no thick pink/white or yellow/white ballast resistance wire, so can only surmise that there is an actual ballast resistor in the white/black feed to the coil located somewhere under the dash maybe. Your comments regarding the starter relay seems int

I have a 4.0 litre Grinnall that is failing to start. There seems to be a lack of 12v to the coil (and incidentally the oil pressure switch too). All dash board lights are OK. The coil is mounted on the near side of the front bonnet support panel, it's a Lucas DLB102 which required a ballast resistor. There is no sign whatsoever of such a ballast resistor within the engine compartment and the wires feeding the coil (White and a white/black) go across to the offside of the engine compartment, along the chassis leg, up over the bell housing and into the passenger compartment near the glove