Club 80-90 Forums

Hi, Ive had a few electrical problems but after checking the wiki and cleaning up the earths and all connections i have had great results. ( now got working lights ) The problem i have is i have two oil senders with a stub of wiring coming from them (courtesy of the mechanic) not connected to anything. The previous owner must have removed this for some reason but i would like to reinstate them. Can anyone tell me if it is possible to rewire these senders and where they get wired to or do i need to install a seperate oil pressure guage? Any help would be great thanks

Herro, There are normally 2 oil pressure switches, one is for the light and the other is for the buzzer,
I replaced engine in mine 7 years ago and there was only a space for one switch, so I earthed the buzzer one and just kept the light one
don't think they go to gauges as they are just switches

Thanks Ben1 i will try earthing the buzzer switch and hope that takes care of that one. Im assuming the warning light one needs to have wire running from the switch to the light to activate it but this is missing. I can easily run a wire but dont know where it connects to. Somewhere in junction box maybe?? One down one to go lol Cheers

Ben1 wrote:There are normally 2 oil pressure switches, one is for the light and the other is for the buzzer

Not quite. The one between the pushrod tubes is used at all times, but the one behind the water pump (I'm thinking WBX here) is only factored in above 2000rpm. Both feed into the oil pressure light control system which lives behind the dash.

Before spending too much time on it, figure out the wiring & control system are all playing correctly. On my '88 2.1, the wiring comes into the engine bay at a two-pin connector forward/left of the engine bay, near the main fuse/relay box in there. One pin does the low-rev sensor, which says "PROBLEM!" if it earths. So leave that one disconnected for the moment. The other pin does the high-rev sensor, which says "PROBLEM!" if it _isn't_ earthed. So, for the moment, earth that one.

You should now have a reliably off oil pressure light. It should do nothing.

Now wire the low-rev wire to the low-rev sensor. You should now have the light coming on before you start the engine, going off almost immediately.

Now just disconnect the high-rev sensor wire. Make sure it can't earth. You should have the light off below 2k rpm, but cries of impending doom coming on immediately and all the time above that speed.

Finally, connect that wire to the high-rev sensor. You should now have a fully working oil pressure light.

If you haven't already replaced the sensors themselves, do so first.

Good write up there Adrian

Just to add, the low pressure switch is the one in between the pushrod tubes and the high is the one Adrain mentions behind the water pump (and a bit of a sod to get at )

Thank you very much Adrian, Step by step guide suits my ageing grey matter perfectly lol. I know where both switches are and they are both new so hopefully i will get them working again. I will give it a go tomorrow to trace the wiring coming into engine bay and keep you posted. I Appreciate your time thanks.
Ghost the mechanic kindly left me a stub of wire connected to the awkward wee bugger. Nice of him i thought lol. Cheers