Oil pressure switch

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Jaba
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Oil pressure switch

Post by Jaba »

I am just a gnats periwinkle away from getting my Hurricane on the road with the engine from the TD Estate.
But as part of the changeover I decided to fit an additional oil pressure gauge by fitting one of those flexible hose remote attached adapters.

Problem : The thread for the oil pressure warning switch is 10mm so the original 14mm switch is redundant. I have obtained two 10mm replacement switches so far but neither work the BX way. Their contact is normally open and it closes when the engine starts.
Has anyone solved this issue and if so which warning switch did you fit that operates the BX way with the switch closed until the engine starts and extinguishes the warning light.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.
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mat_fenwick
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Re: Oil pressure switch

Post by mat_fenwick »

I'm afraid I just used a spare switch I had, origin unknown. The NO contact sounds unusual, but I do know that VW (who use M10 x 1 mm thread for the sender) have a slightly unusual system with one NO switch and a higher pressure NC switch. So I'd steer clear of anything from a VW...

Another solution would be to wire the output from the switch via a changeover relay, to reverse the stte. Bit of a crude method though.
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citronut
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Re: Oil pressure switch

Post by citronut »

sounds a bit odd to me, as the way an oil pressure switch works is, when its under pressure/oil pressure is up it breaks the earth connection the the warning lamp,

so i cant see how they could work the other way round, unless the switch's you obtained are not for oil pressure?????

regards malcolm
curent ride
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also own
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mat_fenwick
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Re: Oil pressure switch

Post by mat_fenwick »

This is how the VW system works, and I had an Alfa a few years back which generally used normally closed switches to operate the warning lights (not certain that included oil pressure) via a circuit which triggered the light. This meant that any increase in resistance of the system (poor connection etc.) would put a warning light on...

...none of which helps find a suitable switch!

EDIT - This gives Intermotor part references which may help.
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1993 1.9 TZD Turbo Estate
1996 3.9 V8 Discovery
1993 VW LT35 campervan
1985 Hyundai Stellar V8
2016 Hyundai iLoad
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Jaba
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Re: Oil pressure switch

Post by Jaba »

Yep that makes sense. The last switch is a black Audi one and is N/O. I will keep trying I suppose as they are not expensive if a few of them do not work.
Thanks for the input Mat.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.
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Re: Oil pressure switch

Post by citronut »

cant you just buy an adapter with a male 14mm thread one end and a female the other end, and a port in the side for the gauge feed,
this way you can use the original switch

rehards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)
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Jaba
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Re: Oil pressure switch

Post by Jaba »

citronut wrote:cant you just buy an adapter with a male 14mm thread one end and a female the other end, and a port in the side for the gauge feed,
this way you can use the original switch

rehards malcolm
Possibly Malcolm. I am trying to work with what I have though. Just ordered a Pug pressure switch. Hope this works as it is holding up the MOT as the warning lights do not work properly without the oil switch in the circuit.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.
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