Could anyone measure their oil sender resistance please?
Could anyone measure their oil sender resistance please?
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Tant

Original Poster:

509 posts

221 months

Wednesday 25th June 2008
quotequote all
Hello all

I'm having a bit of bother with my oil pressure gauge. The gauge was flickng up and down quite wildly on occaisions, which I proved to be the sender as the gauge would read dead steady with a fixed resistor in place of the sender unit.

I ordered a new one but when I fitted it, the gauge hardly registered. They sent me another new sender which has made it read higher but the most I am seeing is about 40 PSI, even with cold oil.

The point is, the pressure seemed right with the origial sender (apart rom the flicking), the engine runs fine, only 50K with a full oil change history from new.

I think the senders are incorrect but I want to try it against others that read about right. The original sender reads 250 ohms when off the car, first replacement rads 330 ohns, and the second replacement reads 290 ohms....so which one is right?

If anyone cold measure theirs by unplugging the wire and testing from the spade connector to earth, I would be really grateful.

Cheers

anthony

greymrj

3,329 posts

233 months

Wednesday 25th June 2008
quotequote all
That is interesting Anthony, I am facing almost exactly the same issue, my sender was damaged, the replacement sender I have does differ and I want to be sure it is measuring correctly.
There is an interesting aside to this. The 'original' sender is very expensive but there are lots of others out there (there were some for sale at a stall at SCH)which will fit the Ford block with or without a simple adaptor. If we know the 'correct' resistance it should be possible to identify other options?

Gerald-TVR

4,896 posts

226 months

Wednesday 25th June 2008
quotequote all
If you can tell me where it is I'll check tomorrow

greymrj

3,329 posts

233 months

Wednesday 25th June 2008
quotequote all
Hi Norman, front, near side, low down on the V6 Cologne engine. It is a cylinder about 1 1/2" dia screwed into the engine with a wire coming out of the top!

Barkychoc

7,848 posts

233 months

Wednesday 25th June 2008
quotequote all
V8S is 290 ohms, just measured it.
I can't imagine that they bothered to sort out a different gauge and sender for the V8, but then this is TVR we are talking about!

jimed

1,508 posts

235 months

Wednesday 25th June 2008
quotequote all
I had some problems with new sender units a couple of years ago. The replacement unit worked fine initially then after a few weeks it went wrong. The replacement one under warranty was so slow in starting to read (12 seconds before the needle moved and then so slowly) and then reading incorrectly anyway that I sent that back as well it being replaced by a slightly used old style one which reads fine (now where's my piece of wood..). Based on that there does seem to be some issues with the replacement ones unless it was a batch issue. The ones I had were brass type of colour and maybe 1.5 ins in dia with a spade connector off it: the thing was marked PTR and then 1000-8N-10 Kn/M2.
Not sure if that helps anyone though.
Jim

Tant

Original Poster:

509 posts

221 months

Wednesday 25th June 2008
quotequote all
Thanks chaps
I think the only thing to do is to buy a capilliary gauge,connect it up, and see how it compares to the electric one.

Cheers
Anthony

Gerald-TVR

4,896 posts

226 months

Thursday 26th June 2008
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Hi

I did measure mine but something is amiss as I got a reading of 46!! dont think my metere is any good

Tant

Original Poster:

509 posts

221 months

Thursday 26th June 2008
quotequote all
Blimey, your pressure must be off the scale!! Did you disconnect the wire first?

cheer
Ant

Gerald-TVR

4,896 posts

226 months

Thursday 26th June 2008
quotequote all
Oh I just measured the resistance between the terminal and the block, wire conneted and engibe and ignition off. How should I have done it?

Barkychoc

7,848 posts

233 months

Thursday 26th June 2008
quotequote all
Gerald-TVR said:
Oh I just measured the resistance between the terminal and the block, wire conneted and engibe and ignition off. How should I have done it?
Exactly the same way Norman but with the wire disconnected from the sender.

Chris

Gerald-TVR

4,896 posts

226 months

Thursday 26th June 2008
quotequote all
Come on this is getting a bit technical for me