What is the usable lifespan for the oil temperature sensor and oil pressure switch? Is there an easy way to tell if they require replacement when the car is not running?
I am eyeball deep in the rebuild of my engine. My plan is to replace most, if not all, engine related electrical wiring, and rubber. So I'm about to place an order for distributor cap, spark plug wires, etc. Wondering if I need to add the oil temp sensor and pressure switch to the growing cart.
Oil Temp Sensor & Pressure Switch - When to Replace
- Dennis Vogel
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Oil Temp Sensor & Pressure Switch - When to Replace
1960 356 S90 Sunroof Coupe
1970 914-6
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- John Brooks
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Re: Oil Temp Sensor & Pressure Switch - When to Replace
Dennis you can test both sensors pretty easy if you have a multi meter, a cup hot water for the temp sensor, compressed air for the oil switch. I have a couple that have been working for 50-60 years and match my engine test bench.
John Brooks
62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965
62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965
- Dennis Vogel
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Re: Oil Temp Sensor & Pressure Switch - When to Replace
Thanks for the suggestion John. Am I measuring ohms? Can you be more specific in what readings I should expect? I am not super savvy with troubleshooting electrical, as you can tell.John Brooks wrote: ↑Wed Mar 27, 2019 4:15 pm Dennis you can test both sensors pretty easy if you have a multi meter, a cup hot water for the temp sensor, compressed air for the oil switch. I have a couple that have been working for 50-60 years and match my engine test bench.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S
1970 914-6
2014 Carrera S
- Dave Wildrick
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Re: Oil Temp Sensor & Pressure Switch - When to Replace
A few years ago, I tested my 2 original 6V temperature sending units (made in the '60s).Dennis Vogel wrote: ↑Thu Mar 28, 2019 1:29 pmThanks for the suggestion John. Am I measuring ohms? Can you be more specific in what readings I should expect? I am not super savvy with troubleshooting electrical, as you can tell.John Brooks wrote: ↑Wed Mar 27, 2019 4:15 pm Dennis you can test both sensors pretty easy if you have a multi meter, a cup hot water for the temp sensor, compressed air for the oil switch. I have a couple that have been working for 50-60 years and match my engine test bench.
They each gave an ammeter reading of 28 ohms at room temperature (75-78 degrees F) and 35-36 ohms at 162 deg. F (72 deg. C) in hot water.
The 28 ohm reading at room temperature agrees with what electrics guru Joe Leoni told me it should be.
Dave Wildrick
Houston, TX
#10230
64C coupe
65C coupe
Houston, TX
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64C coupe
65C coupe
- Dennis Vogel
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Re: Oil Temp Sensor & Pressure Switch - When to Replace
Not sure if I did this right. I have cheap multimeter with limited options. I set it to measure resistance (ohms). I put the red (positive) lead on the sensor end, and the black (negative) lead on the connector end.Dave Wildrick wrote: ↑Thu Mar 28, 2019 3:49 pm A few years ago, I tested my 2 original 6V temperature sending units (made in the '60s).
They each gave an ammeter reading of 28 ohms at room temperature (75-78 degrees F) and 35-36 ohms at 162 deg. F (72 deg. C) in hot water.
The 28 ohm reading at room temperature agrees with what electrics guru Joe Leoni told me it should be.
For the temp sensor, I got:
- 45 ohms at 180 F
- 41 ohms at 170 F
- 28 ohms at 72 F
For the pressure sensor was a bit wonky. I got:
- 0.x with nothing going
- OL (think this is overload) when using compressed air
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S
1970 914-6
2014 Carrera S
- Martin Benade
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Re: Oil Temp Sensor & Pressure Switch - When to Replace
Both sound good. The pressure switch is zero ohms, as in fully connected at zero pressure. Once you get above 7 psi or so the contacts open, your meter basically said it was such high resistance that it could not measure it. That's OK.
Cleveland Ohio
62 Cabriolet
56 VW
02 IS 300
04 Sienna
62 Cabriolet
56 VW
02 IS 300
04 Sienna