Low Oil Pressure

[Tom Hall]

I’ve recently acquired a Series II 1.3 Zagato which is in excellent condition but has unsettling habit of showing zero oil pressure when travelling. On starting there is good pressure but it can drop after a few miles. There are no sounds to indicate knocking etc. The odometer reads 81,000 miles.

I purchased the car from a reputable dealer and have returned it for attention - they have shown by fitting an external gauge it gives a good oil pressure.
I think I have read somewhere that this is a gauge fault and that an additional gauge can be fitted for peace of mind, is this correct?
Thanks for any help you may be able to give.

[GG]

try changing the oil pressure sending unit at the engine. Had the same problem, and this fixed it.

[Tom Hall]

Thanks for the speedy reply, it shall be done come the new year.

[lancialulu]

Welcome to Fulvia land!

Just be careful in selecting a replacement oil pressure sender unit. Two types depending on whether Veglia or Jaeger. Originals are no longer made. Some replacements are 0-10 bar or 0 to 8 bar. Your car would have had (fairly certainly) 0-7bar (0-100psi) if Veglia, which are not readily available. Earlier Fulvias were 0-6 which will show on the gauge as higher oil pressure...

[Tom Hall]

Thanks, all info gratefully received!

[GlynW]

Hi Tom,

Congratulations on your purchase!  I hope that changing the sender for an appropriate unit will at least give you a consistent and reliable reading, even if the absolute values need to be measured using an external gauge.  If problems persist, in the long-term it may also be necessary to clean the contacts between the oil pressure gauge and the printed-circuit board that it is mounted on.  That's not a job for the faint-hearted or your first Lancia experience, but one which was recently described on this Forum by Norm Thomas in his  'Slow Rebuild' thread and might be tackled by your sellers.  

Norm and I are currently working on an Owners Guide that will incorporate some of his material but it may help you now to have a draft (& unchecked!) version of the relevant section.  Being Christmas, Norm and I have downed tools until New Year, so we will not make more progress until then.

Best wishes,

Glyn

[Tom Hall]

Thanks Glyn I’ll look it up, I’m not too worried about absolute values, a general indication would be acceptable, a gauge showing zero goes against my principles.

I’ve come to the Fulvia after 27 yrs ownership of a TR5, so it’s a case of beauty and the beast…

Tom

[Wangler]

This might be of interest. The oil pressure senders are often faulty and correct replacements seem unobtainable. I’ve tried very hard to find one with no success.

https://forum.viva-lancia.com/viewtopic.php?p=1445027&hilit=Oil+pressure#p1445027

[Paul_lancia]

If you’re after a new pressure sensor then Pieces-Fulvia in France or Omicron in the Uk could help.

https://www.pieces-fulvia.com/oil-pressure-sensor-lancia-fulvia-all-models.htm

https://shop.omicron.uk.com/products/oil-pressure-sender?_pos=8&_sid=9fa8a0273&_ss=r

There are also parts on eBay.it which describes the part as - Oil pressure bulb Lancia Fulvia COUPE, BERLINA and ZAGATO all models 1200/1300/1600. Pressure 0-8 Bar. Works with Jager and Veglia instruments.

https://www.ebay.it/itm/196441201432?_skw=sensore+pressione+olio+fulvia&itmmeta=01JG7BVDT66X832MEH9TXC8ANM&hash=item2dbccedb18:g:8D4AAOSw6~1maeOB&itmprp=enc%3AAQAJAAABAHoV3kP08IDx%2BKZ9MfhVJKlGO0nsphsmlzoOHj8ruNsYwqUJhTuTUDJMlXbfWHGPLEeVW3FPXgUTr7q9AuBwtILEUzLHUBswuUZBOVfEgt60ul%2BMtGyJcar8OJ3SGemnoGvqteTbUTyb4IaSnUWCqikWYBnnUQiHlPCBCCAx%2BGZYzh2FRKBbqexeE7Y5SL7T%2Bfdh67vnpNbSm5ynkaNAQjaNsnG80J%2BXFgkZ00E5G7RnUs788%2FZQ7aBeeQs0eTiaMYFUjR3GWyiTGZRTnKwUIbMnS2MW7v%2Fg%2BbptfXIC1c7MLwR43%2FChx%2Bz72Jg9lcqljpbyrDN6heCGlikC%2FZ0nBI4%3D%7Ctkp%3ABk9SR5jd7euBZQ

Of course an incorrect reading on the gauge could also be a wiring issue or a gauge/ instrument issue. You could check with the engine off vs running if you have any resistance change on a multimeter. (Pin to body which is grounded via the engine.)
You’d need to open the wire to the instrument panel to measure to eliminate any wiring shorts.

[nistri]

Oil pressure sensors are known to become faulty and of course the wiring might be dodgy. However, the whole system is calibrated to a max pressure of 6 bars. If the sensor is calibrated to 0.8, the gauge will consistently read low pressure unless the oil is very cold (ie when starting the engine).

[Wangler]

Oil pressure sensors are known to become faulty and of course the wiring might be dodgy. However, the whole system is calibrated to a max pressure of 6 bars. If the sensor is calibrated to 0.8, the gauge will consistently read low pressure unless the oil is very cold (ie when starting the engine).

From Omicron’s website:

“Original was 0-6 bar, but unavailable for many years. This means that at low engine speeds and warm oil temperatures the gauge will read very low. This is normal, and so long as the gauge responds to engine revs then you probably don't have anything to worry about. For piece of mind, fit a known 'master' mechanical gauge to the car to check the idle pressure.

Suits all models and Jaeger/Veglia instruments.”

That’s why I fitted a new mechanical guage. I like accurate gauges.

Also I understand from an article by Huib that the sender has a coil in it and it can be repaired if it’s become worn or clogged. As the correct senders are unavailable it may be worth trying to fix the old one. Huib’s article about this is on the Viva Lancia website.

https://viva-lancia.com/fulvia/qanda/engine/oilpress2.php

[Spider2]

What I love about this forum is that it is rare that I do not learn something useful every time. I have just learnt that the 0-25-50 scale on my oil pressure gauge is in decibars. I had always assumed it was PSI. Only the Italians would use decibars!
Also I was always a bit worried about the pressure going off scale, especially when cold.  I have a 0-6 bar transmitter and as the relief valve operates at 6.2 bar the relief valve operates outside the range of the gauge. Interestingly I have a Veglia gauge but a Jaeger transmitter.

[Tom Hall]

Thanks all. Been off-air for a bit, but appreciate your input.

[lancialulu]

What I love about this forum is that it is rare that I do not learn something useful every time. I have just learnt that the 0-25-50 scale on my oil pressure gauge is in decibars. I had always assumed it was PSI. Only the Italians would use decibars!
Also I was always a bit worried about the pressure going off scale, especially when cold.  I have a 0-6 bar transmitter and as the relief valve operates at 6.2 bar the relief valve operates outside the range of the gauge. Interestingly I have a Veglia gauge but a Jaeger transmitter.

I think the gauge needs to be matched to the transmitter. I have both on the shelf so when I get an idle moment I will do a little test....

[Paul_lancia]

For info - I read the sensor engine off/ cold resistance of my S2 sensor and it was about 700 ohms - still connected to the gauge.