Smiths Oil Gauge

[Andrew S]

This may be a stuoid question but, do these gauges after removing bleed themselves?

I removed my oil gauge as I just cant see it when illuminated compared to the other dials. I broke the green shield off inside, whcih is just a tiny sheet of geen next to the bulb. I can now see it, except the oil pressure readings are so long since. The needle is not fowling the dial that I can see and where I used to have reading on idle of between 40-50 when cold on idle, I will be lucky if it goes up to 30 when revving the engine from cold.

Is this aid does anyone think as teh pipe was removed for the job?

Any commets or advice much appreciated

Alan, are you there?

Andrew

[wilf]

I don't think the gauge cares if the pressure it "sees" is oil or the air in the pipe compressed by oil further down it.

They are finicky little bu**ers, maybe something else has changed within it?

[jleyton]

I had a problem like this and removed the pipe behind the gauge and poured in a little 3in1 oil.

It made a significant difference. I reckon some air was trapped and although oil is incompressible, air can be compressed. I reckon this was giving me some odd readings.

Cheers

Julian

[Jeff]

I had a problem like this and removed the pipe behind the gauge and poured in a little 3in1 oil.

It made a significant difference. I reckon some air was trapped and although oil is incompressible, air can be compressed. I reckon this was giving me some odd readings.

Cheers

Julian

I was just about to type the same thing Julian but you beat me to it

[Princejohny]

I had a problem like this and removed the pipe behind the gauge and poured in a little 3in1 oil.

It made a significant difference. I reckon some air was trapped and although oil is incompressible, air can be compressed. I reckon this was giving me some odd readings.

Cheers

Julian

I had a similar problem and pulled off the clear plastic pipe from behind the gauge, which seemed to have an inch or so of air at the end. I used a little pipette to top it up with engine oil, pushed it back on quickly and fixed it.
Cheers Johny

[wilf]

Air is compressible, but it makes zero difference in an oil pressure gauge feed line or any other line - whatever pressure is present at the engine line will be transmitted to the other (gauge) end.

My gauge line is nearly 100% air and it works fine.

[jakesmig]

Air is compressible, but it makes zero difference in an oil pressure gauge feed line or any other line - whatever pressure is present at the engine line will be transmitted to the other (gauge) end.

My gauge line is nearly 100% air and it works fine.

Ditto, 10 seconds after startup the air is as compressed as its going to get.

[jleyton]

Maybe, but I reckon it can still give you irregular or misleading readings. It's a bit like using a towrope with a spring at one end.

Anyway, speak as you find, it certainly made a difference to mine and it seems like I'm not alone.

Cheers

Julian

[Andrew S]

Thanks for the advice. I have tried filling up the pipe feed with oil and even to the point that I undid the pipe whilst the engine was running and you coudl see the pipe fill up. No difference at all. I then noticed that the needle was not pointing to the 'O' on the gauge and maybe as suspected, when I broke off the green lens for the bulb inside, I must have buggered up the calibration. I then gently bent the bar round so that the needles was reading zero. Fired engine up and now it is higher reading but wont go past the 40psi, which is where it normally ticks over.

I have a feeling that I now need to look for another gauge to match mine. What a pain but I only need an oil unit and not worried about the dial facia etc and mine is all new and interchangable.

Wish I never bloody touched it now

Cheers
Andrew

[jleyton]

Hi Andrew,

Have you seen this thread ? (look at the last few posts) http://www.stag.org.uk/forum/showthr...ight=moraystag

Mike borrowed my spare OPG and proved to himself that his was playing up - he's now returned mine to me. You're welcome to borrow mine to do the same thing if you want.

If you're interested then just drop me a PM.

Cheers

Julian

[Andrew S]

Hi Julian, thats very kind of you, PM sent

[Moraystag]

I had poor readings from my gauge and bled it by slightly loosening the nut at the threaded connection at the back until oil seeped out and all the air was out of the plastic tube, I have a transparent line.
I swapped over the gauges a few times once the car was at full temp repeating this using Julians gauge and then mine.
It was'nt until I compared the two that I noticed that when my own gauge was not pressurized the needle was to far past the zero, subsequently giving me a poor oil pressure reading compared to Julians gauge which sits bang on zero when not under pressure.
The removing of the air in the tube did make a slight difference to the reading on my own OPG.

Mike

P.S Julian did you recieve your OPG through the post yet after my daughters fiasco????

[jleyton]

Hi Mike,

Yep, sorry, it arrived yesterday. I've unpacked it, but now got to pack it up again to send off to Andrew

Cheers

Julian

[Moraystag]

Good stuff Julian sorry for delay mate

Mike