Oil pressure sensor relocation

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vulcan1208

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Can anyone forsee a problem if a copper pipe were to be connected to where the sender mounts and the pipe routed to somewhere in the engine bay where a slightly larger sender could be mounted ?
 
It might be a *little* helpful if you mentioned what car / engine this was ;)
Certainly for the 4200 @Zep created an adaptor that allowed a generic sensor to be used.

From a *physical* point though, I can't see that what you propose would be too much of an issue

C
 
Sorry, it's a 3200. I have had the car for many years and would like to sort out the pressure sensor issue once and for all, I would also like to tee of a connection for an "analog" guage.
 
vulcan1208 said:
Sorry, it's a 3200. I have had the car for many years and would like to sort out the pressure sensor issue once and for all, I would also like to tee of a connection for an "analog" guage.
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The 3200 experts will be along (@allandwf ?) but that sounds to me like a really good idea!

C
 
vulcan1208 said:
Can anyone forsee a problem if a copper pipe were to be connected to where the sender mounts and the pipe routed to somewhere in the engine bay where a slightly larger sender could be mounted ?
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allandwf said:
There's not a lot of room to do either, let alone mount it where vibration wouldn't fracture a hard pipe.
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I would be pretty nervous of doing this TBH. A proper oil pressure braided line maybe.
 
Thanks everyone, I am having a braided hose made up with 14x1.5 male on one end and 14x1.5 female on the other, the hose will be long enough to use an anti vibration mount to affix the sensor to a suitable position in the engine bay away from too much heat.
 
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Lozzer said:
I would be pretty nervous of doing this TBH. A proper oil pressure braided line maybe.
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Copper or even nylon pipe is very commonly used for mechanical oil pressure gauges in older cars. My Stag uses a nylon pipe for the oil pressure gauge.
 
would be great to see what you end up with here!! i would echo some concern about the pipe breaking and causing a much bigger issue than a blinky sensor. We all agree a reliable pressure sensor would be a joy given how flakey they seem to be.
 
Out of interest why isn't something like a defi pressure gauge used? Less piping.
However if this is a thing I have access to instrumentation standard stainless capillary tube and gyrolocks if you know lengths and i/d requirements. As its good enough for cyclic endurance gas turbine testing I'm pretty sure what it would go through on a car would be very small beer.
 
mjheathcote said:
Copper or even nylon pipe is very commonly used for mechanical oil pressure gauges in older cars. My Stag uses a nylon pipe for the oil pressure gauge.
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The braided pipe with 14x1.5 fittings (right angle fitting at engine block end) is being made by HEL performance. The engine bay (sensor) end will have an additional 1/8 take off for fitment of an analog guage, the guage has a rear 1/8 fitting so can be left connected to give a 100% reliable pressure reading in addition to the dash guage. I will upload pictures when done and working.
 
vulcan1208 said:
The braided pipe with 14x1.5 fittings (right angle fitting at engine block end) is being made by HEL performance. The engine bay (sensor) end will have an additional 1/8 take off for fitment of an analog guage, the guage has a rear 1/8 fitting so can be left connected to give a 100% reliable pressure reading in addition to the dash guage. I will upload pictures when done and working.
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I'll be interested to see how and where you mount it all.
 
Diavolo Nero said:
Out of interest why isn't something like a defi pressure gauge used? Less piping.
However if this is a thing I have access to instrumentation standard stainless capillary tube and gyrolocks if you know lengths and i/d requirements. As its good enough for cyclic endurance gas turbine testing I'm pretty sure what it would go through on a car would be very small beer.
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i think the issue is integrating the reading into the dash and the error warnings. If an independent pressure reading was all that was needed i am sure there are many smaller and more reliable options. The problem is the pressure sensor is a variable resistance to ground (there is a mechanical wiper and a carbon track inside with with something like a bourdon tube sensor). While its possible to have a solid state sensor in the engine and a little electronics box that converts that into a variable resistance emulator for the system reading, i suspect most owners would not be happy with the cost and complexity of this solution. I am working on modifiying a current variable resistance sensor with some mods to try and make cheapish, more reliable but compeltely compatible alternative for this for these very reasons! its in test at the moment so not there yet.
 
davy83 said:
i think the issue is integrating the reading into the dash and the error warnings. If an independent pressure reading was all that was needed i am sure there are many smaller and more reliable options. The problem is the pressure sensor is a variable resistance to ground (there is a mechanical wiper and a carbon track inside with with something like a bourdon tube sensor). While its possible to have a solid state sensor in the engine and a little electronics box that converts that into a variable resistance emulator for the system reading, i suspect most owners would not be happy with the cost and complexity of this solution. I am working on modifiying a current variable resistance sensor with some mods to try and make cheapish, more reliable but compeltely compatible alternative for this for these very reasons! its in test at the moment so not there yet.
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Guess you would need to look at the values that the defi resistance sensor gave out in comparison. However has made me think of another issue. Is it possible that the degradation of the wiring has changed the resistance value of said wiring enough to affect the reading?
 
This is the resistance profile of the original compared to my replacement that I am working on, measured directly from a newish original sensor.1740404011725.png
So you are still looking at around 75 ohms at maximum pressure and i suspect the wiring would struggle to add a few ohms to that. If you had a very corroded contact you might get unlucky, but i dont think the wires are the issue. The original problem is two spring contacts in the device one that makes contact to a ceramic circuit with the resistor on it and the second is a spring contact onto a pin in the rear body. I think the one that goes first is the sping contact to the outer pin. I have used high temp solder and secure all of this so there are no "touch" contacts internally and this should stop it self-destructing so quickly i think.
whether DEFI have a sensor with this precise resitance profile it's hard to say.
 
davy83 said:
This is the resistance profile of the original compared to my replacement that I am working on, measured directly from a newish original sensor.View attachment 136397
So you are still looking at around 75 ohms at maximum pressure and i suspect the wiring would struggle to add a few ohms to that. If you had a very corroded contact you might get unlucky, but i dont think the wires are the issue. The original problem is two spring contacts in the device one that makes contact to a ceramic circuit with the resistor on it and the second is a spring contact onto a pin in the rear body. I think the one that goes first is the sping contact to the outer pin. I have used high temp solder and secure all of this so there are no "touch" contacts internally and this should stop it self-destructing so quickly i think.
whether DEFI have a sensor with this precise resitance profile it's hard to say.
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Fair enough, it's not that sensitive then. I had a brief look to see if there was a profile for the defi but nothing immediate popped up.
 
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