adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

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Dan Timberlake
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adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by Dan Timberlake »

A few decades back some (Bosch?) oil pressure switch had the rep for having a set point higher than the typical very low maybe 3 psi "light on " pressure.

Does such a thing exist today?

Also, a switch that kicked "on" at 30-35 psi would be handy for fuel injected cars.

The Stewart Warner 5000 Series online info is deplorably incomplete as to chemical resistance.
The best I could find is Polyimide diaphragm, some of which are gasoline resistant.

thanks,

Dan T
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Re: adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by splinter »

Longacre may have something for your applications:

https://www.longacreracing.com/products ... 26-Senders
bill jones
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Re: adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by bill jones »

---here's a list of new old stuff I accumulated many years ago---and still have most of it
---if you see anything you might be interested in I could check it for sure to make sure it does what you want

-----------------------------------------------------------------------------
Pressure switches ---Hobbs (Honeywell) & Faria
---typical uses are :
Hobbs switches
---the NC Normally Closed side of the Hobbs #76074 60 is for low oil pressure light like where you might want to have a low oil pressure awareness light for a race engine to come on around 40 to 60PSI rather than down low like the 7 to 13# stock type switches

---the NO Normally Open side of the Hobbs #76074 60 to turn on when the pressure reaches the set point.
---this allows you to become aware of mechanical fuel injection pressures without ever having to look at a fuel pressure gauge

$40 each---11 Hobbs #76074 60n DC (dual circuit)---3 terminals are NO---NC---ground
---rubber plug at top of plastic tower allows easy access to the adjustment screw
---on NC---the light come ON at about 65 PSI and stays on above 65PSI as pressure rises
---on NO---the light comes on at about 55 PSI and stays on down to zero as the pressure drops
---the switch contacts are rated for 8 amps at 12VDC
-----------------------------------------------------------------------------------------------------
Faria switches
$ 30---one Faria Corp #2901-05-c8 externally adjustable---set at 17.0#---3-3/4 turns down

$ 30---one Faria Corp #2901-05-c8 externally adjustable---set at 18.0#-------4 turns down

$ 30---one Faria Corp #2901-05-c8 externally adjustable---set at 20.0#---4-1/4 turns down

$ 30---one Faria Corp #2901-05-c8 externally adjustable---set at 21.0#---4-1/2 turns down

$ 20ea-six Faria Corp #2901-05-c8 externally adjustable---grounds thru the housing

---the adjustment screws have been loosened up to allow adjustments on several units
---these are the NO (Normally Open) units

--screws are down from top of the case ----light is on----- down
---one is adjusted---------------------------------zero to .5 PSI----.053”
---one is--------------------------------------------zero to 22.0 PSI---.225”
---one is still sealed------------------------------zero to 6.0 PSI----NA
---one is still sealed------------------------------zero to 5.5 PSI----NA
---one has the adjustment screw exposed-----zero to 6.0 PSI----.104”
---one has the adjustment screw exposed-----zero to 8.0 pSI----.090”

$ 20 each---are in yellow boxes---Faria Corp part #2901-10 imprinted on top of metal sensor cases
---there are NEW---old 1968 era surplus parts
---has two terminals---one is for 12vdc to the light---other is to ground
---these are a NC switch---means the switch is on with pressure above 4 PSI and off below 4 PSI

---in the top center of the steel case is an indent with a small straight screwdriver slot embedded in with
Loctite or epoxy
---this screw allows the pressure setting to be changed---but was NOT designed to be re-adjusted
---so it is somewhat of a challenge to remove the epoxy or Loctite to where the screw can be adjusted
---but it can be done
--------------------------------------------------------------------------------------------------------
$20 each---40 tan boxes---Faria Corp #2901-05-C8 is imprinted on top of sensor case

---these are new---old 1968 era aircraft surplus parts with tag nomenclature:
---5930-654-4415---switch---oil pressure---1Ea.---DSA-900-67-TC43---A---1/68---P/N H15757

---one terminal and switch terminal must be must be grounded---has 1/8NPT and 3/4” hex for wrench

---these are NO---Normally Open---meaning a test light is off above 6psi and will come on when the pressure drops to 6psi and below

---in the top center of the steel case is an indent with a small straight screwdriver slot embedded in with epoxy of Loctite
---this screw allows the pressure setting to be changed---but was not designed to be re-adjusted\---so it is somewhat of a challenge to remove the eopxy or Loctite to where the screw can be adjusted---but it can be done

---the distance down to the top of the screw is .095” to start with---set at about 6psi
------------------------------------------------------------------------------------------------------
---the adjustment screw allows the switch to be adjusted anywhere between about 3psi to 21psi
---3psi is about two turns up from .095”

$20---one Faria Corp 2901-05-C8 factory set at---5.5psi---.095” down
$20---one Faria Corp 2901-05-C8 factory set at---6.0psi---.095” down

$30---one American Standard 2901-3 L6---externally adjustable---set at 12.0PSI---2 turns ??????
------------------------------------------------------------------------------------------------------------
$ 20 each---3 Faria Corp P/N 2904-10-L6
---one turns on a light at 3.8psi and above---is off below 3.8psi
---one turns on a light at 3.4psi
---one turns on a light at 7.0psi
-------------------------------------------------------------------------------------------------------------
$ 30---Faria Corp 2901-05-C8---externally adjustable---is set at 21psi---4-1/2 turns
--------------------------------------------------------------------------------------------------------------
$ 20 each---6 Faria 2901-05-C8---single terminal---grounds thru the housing
-------------------------------------------------------------------------------------------------------------
---probably the Hobbs switch
---3 terminal---has a 7/32” .219” female hex for adjustment
---top of tower to bottom of hex = .350”
---hex is easily adjustable but didn't test the range of this switch
---the NO Normally Open circuit turns an a light from 30psi down to zero
---the NC Normally Closed circuit turns on a light at 38psi and higher
-----------------------------------------------------------------------------------------------------------------
---have 40 in tan boxes---#5930-654-4415--switch, oil pressure---DSA-900-67-TC43---A 1/68
---p/n H-15757---6psi----black housing has 2901-05-C8---single terminal
----------------------------------------------------------------------------------------------------
---have 15 pieces Hobbs 76074-60--------three terminal---dual circuit
---have 3 pieces Hobbs 76054 60 N/O ---two terminal
Geoff2
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Re: adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by Geoff2 »

VDO makes the adjustable switch you need, 1/8"NPT.
#230.991 20-60 psi
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Re: adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by In-Tech »

bill jones has it correct. use amazon or ebay and type hobbs switch in the search and you can find all the fixed or adjustable you desire without having to pay three times the price from a vendor repackaging a standard honeywell hobbs switch.
Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: adjustable or 10-15 psi oil warning light switch - also 30 psi low fuel pressure switch.

Post by David Redszus »

Most data collection systems provide high and low pressure alarm warnings on their displays.
Not only will pressure (or temp) values be displayed, they can be recorded as well.

They work with any pressure sensors.
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