Alfa GTV6 Oil Pressure Gauge

[Fylnn]

I am in the hopefully final stages of putting back together my 1983 GTV6 as a PRC rally car.  Same idea as Greg's excellent post but just taking a lot longer.  I seem to be in the 3 steps forward, 2 steps back phase so I have a series of questions to tap the combined wisdom.

First up is the oil pressure guage is not functioning.  I am trying to diagnose what it is before I start replacing things.  Not sure how it reads, but earthing the sensor wire from the gauge into the block produces nothing.  Also the sender reads as infinte resistance and that does not seem to change even with the engine started.  I have installed a warning light sender on a tee piece just to be sure.  I would rather not rely on the gauge entirely.  When I bought the car it had a mechanical gauge so something is obviously faulty.  I did reconnect the electrical one and it did work for a while.  Since then the engine has been out and back so now no go.

So anyone ever tried to diagnose whether it is the gauge or the sender?  Any hints what to look for?

[Jekyll and Hyde]

Well, you've already proved the guage or the wiring to it (or your engines earth strap) is faulty, I'm not sure what more help you need? Fix that, then work out if a new sender is required (sounds possible).

[Fylnn]

so if I earth the sender wire, the gauge should go to full deflection.  I suppose that was my question really.

[Jekyll and Hyde]

so if I earth the sender wire, the gauge should go to full deflection.  I suppose that was my question really.

Correct.  If not, circuit is incomplete or guage faulty.

[david sammartino]

i have a gauge cluster, as in the complete centre piece with water, fuel and oil, from an 84 gtv4, which should all work fine in the gtv6.
you can have the lot for 30 bucks plus postage as im in melbourne.

[Fylnn]

OK will check the wiring continuity.  Hopefully a lose wire and not the gauge.  I will keep David's instrument cluster in mind.  I assume that the fuel gauge senders are compatible with the GTV6 tank.  Should get back to the shed this weekend.