Happy Days

[niduncan]

Bill,

 

Had a look in the Haynes manual and it looked as if the Sierra sender unit

has more than one sensor in it. Only one option, out came the sender unit.

The unit actually has three sensors combined in it:

 

Sensor 1: gives a low resistance on empty and high resistence on full.

Sensor 2: gives the opposite, high on empty and low on full.

Sensor 3: suspect this is used to control a dashboard low fuel level light.

 

Connected up Sensor 1 (was using Sensor 2) and now the VDO guage indicates

1/4 full when empty and full when full which is somewhat better than working

backwards. I will live with this until I fit the VDO sender. The VDO

sender will fit nicely in the current hole in the tank but I then have to

figure out a way of getting a fuel pickup pipe into the tank.

 

Nigel.

[Big Jim]

Alternatively, you move the actuation arm on the sensor relative to the "pick up" on the resistor board, so that it reads correct on low fuel (ie ½ tank down to empty) but only starts to read at about ¾ tank, until then it's off scale on the sender so doesn't read. This is how mine is, I want to know when I'm getting towards running out, not how full it is.

[niduncan]

Tried moving the actuator arm but the VDO guage needs a resistance of less than about 5 ohms to read empty, the lowest I could get out of the sierra sensor was 36 ohms which indicates 1/4 full. Can't see any way of getting the resistance lower. Any electronic whiz kids out there who could design a circuit to convert an input of 36 to 195 ohms to give an output of 3 to 183 ohms. Must be a challenge worth a slab of beer!

[Guest Ianz]

The VDO guage must be arse about faced.ie less resistance means guage

should show more fuel!!!!!!

Tried moving the actuator arm but the VDO guage needs a resistance of less than about 5 ohms to read empty

For example if you earth the wire from tank sender to guage(this will be an effective resistance of 0 ohms) it will show a full tank

not the other way round.

 

IMHO

Cheers Ian

[Guest Ianz]

Anyways this forum is definately chinese whispers!!!!!!!!!

 

How did we get to discussing driving in the sun to discussing fuel senders???????????????????????????????????????????????

[Guest Russler]

I have exactly the same prob with my vdo gauges, however it is going to have to wait until after my exams. Then I will make a little circuit to do the conversion, if you are still having problems in a month or two let me know and i am sure I can make two.

[niduncan]

Indeed the VDO gauge works backwards. If you do not connect a sender to the gauge i.e high resistance the gauge reads full. If you connect the gauge to earth it reads empty. Must have been a Monday morning design by VDO or could be something to do with the fact that these clocks are actually designed for the marine market as the sender unit came with instruction for fitting in a boat! I suppose that raises the question "Has anybody managed to make an amphibious Robin Hood?"

[Guest Roger 2B]

STOP

 

This thread was supposed to be about enjoying a drive in the sun. It went to guages, and now it involves water.

[Guest Andy Rathbone]

i want do drive mine in the sun :boohoo: :boohoo: :boohoo: :boohoo: :boohoo: :boohoo:

but i cant its not quite finished :boohoo: :boohoo: but sooooon i will be there

just driving for the sake of it and looking forward to it lets hope i havent missed the summer

[niduncan]

Sorry - things did go off at a bit of a tangent. Must have been due to the shock of having a sunny weekend.

[Guest Roger 2B]

During the recent sunny weather I have managed to get a few runs around the Lincolnshire countryside.

 

Just a bit of a problem though, I found that every so often the steering starts pulling. Sometimes to the left, but sometimes to the right. Fortunately, every time I stopped to investigate there was a pub - so I was able to get a drink while I sat and looked at the car. This seemed to cure it for a while, but it kept coming back.

[Robbie 2B]

I hate Speed Bumps!!!!! :gdit:

 

But all in all the weekend was great fun , and looking 4ward to Stoneleigh, more of the same weather please.