Oil Pressure gauge

[dozzum]

My new oil pressure gauge and sender turned up today, but couldn't get them to work.

They are both VDO and both 5 bar.
The sender is this 2 pole one. http://www.ebay.co.uk/itm/260973546646? ... 047wt_1037
and the gauge is this one. http://www.ebay.co.uk/itm/150788036956? ... 500wt_1287

There are three connections on the back of the gauge. Positive, earth and one that I am assuming to be for the sender.

As soon as I connect the positive and earth I get full deflection to the right, this doesn't change when I connect the sender wire.

I screwed the sender into the right hand side of the head in place of the oil pressure switch that was there before. Is this the right place for it?
There was no washer with the sender so I used a copper one. Does it need this/is it a problem?
I used one of the poles for the gauge and one for the MFA buzzer wire. Is that how it is supposed to work and does it matter which pole you use for which?

Cheers guys

[go-for-it1]

I can't see the ebay links as I am at work but i suggest you first swap the Pos and Neg wires around on the gauge. The gauge should show zero even with power on. The other connection, usually marked with a "G", is for the sender. If you get the gauge to read zero with the pos and neg reversed, connect a wire from the gauge connection "G" and earth it and the gauge should go to full deflection, that proves the gauge is ok. If I remember correctly the top of the sender should be marked with a G on the pole for the gauge. I can have a look at mine tomorrow if you want and confirm this?
Yes you need a washer and copper is ok.
Sender in right side of head is correct where blue wire is.
The other pole on the sender, which you connect the original blue wire to is not for the buzzer it is for the oil pressure lamp (orange) on the dash and gives warning when pressure is low.
Rob

[dozzum]

I think I have solved the issue,
It seems I have bought a sender for use on boat engines. So the reason it has 2 poles is not for one to go to the warning light and gauge as I had wanted.
One is for the gauge and the other is for earthing the sender as it does not earth through the head. According to the VDO instructions for marine gauges that is how the marine senders are wired.
I have come to this conclusion as I was getting an open circuit reading from either of the sender poles to earth but 10 ohms across the two poles (which is what you would normally expect from pole to earth.
This is rather annoying as now I have nowhere to plug my oil warning light into.
I have left the gauge at home so I will have to wait till Wednesday to test the two together I got my brother to test the gauge following VDOs instruction manual and its all good.

[go-for-it1]

You will be able to fit the oil warning lamp sender if you fit a tee piece and screw them both in to it. Don't forget that the threads are M10x1mm as some tee pieces advertised online are UNF or NPTF American threads. Here is a link to show you what I mean but this tee piece has the wrong thread so search online for the right one (ebay?)
http://www.holden.co.uk/displayproduct. ... de=070.252" onclick="window.open(this.href);return false;
Rob