Oil Pressure Sending Unit w/Guage - 1/4", 18 or 1/8, 27 - How to know what size?

[90V6RedHotLuminaEuro]

Good Day! I hope All are having a pleasant day.

 

Regarding the Oil Pressure Sending Unit w/Guage... is there an easy way to know what size, 1/4" - 18 Thread, or 1/8" - 27 Thread, the fitting is? I'd hate to have to remove it to find out what size it is, then put it back, order it, then remove/replace it again. It's not the easiest thing to monkey around with. I have a 1990 Chevrolet Lumina Euro Coupe, V6/3.1 VIN 2G1WN14T0L9204242

Thanks,

 

Happy Fourth (4th) of July!

 

John B.

[19Cutlass94]

1/4"- 18 thread.

 

The 1/8" - 27 is for the 2.8L

[90V6RedHotLuminaEuro]

1/4"- 18 thread.

 

The 1/8" - 27 is for the 2.8L

 

Thank You so much! I called RockAuto, where I usually get my parts from, but they didn't know and said I'd have to remove it to find out. I didn't think that was true. I looked on Ebay and found several listings where the 1/8"-27 was specified for the 3.1/v6, and the 1/4"-18 specified for the 2.5L. I found another listing where the 1/8"-27 was specified for the 2.5L. I was leaning toward the 1/4-18, just with a practical theory, and lack of any other ideas, that the bigger the engine, the larger the fitting. This is good news in that the 1/4" is cheaper than the 1/8" at RockAuto.

 

[RobertISaar]

original part numbers for a 90 lumina 3.1:

 

switch: 25036940

sensor: 10201491

 

looking up 25036940 shows the 1/8 X 27 unit.

looking up 10201491 also shows the 1/8 X 27 unit.

[19Cutlass94]

Thats weird, everything Ive always worked on and read, was a 1/4" - 18. But then again where talking about GM here...

[RobertISaar]

i'm not saying you're wrong, but those are just the numbers i pulled from alldata and cross-referenced online. alldata has been wrong before.

[19Cutlass94]

But then again were talking about GM so who knows what they did

[RobertISaar]

yeah, could be anything really.

 

and alldata's info came from GM.... so a couple of different layers of potential fail.

[90V6RedHotLuminaEuro]

I went to the Borg Warner site and used their cross reference facility to do some research. I also used some other sites, and Ebay. I found some contradictions

 

 

For the LUMINA 92-90

= 1/4"-18 = BorgWD 4088 = AIRTEX 1S6635 = WELLS PS220 = AIRTEX PS220

Alternate/OEM Part Number(s): 10068563, 10096169, 10096178, 10137630, 10137652, 10191433, 10201489, 10201490, 10205676, 10207183, 10243574, 12553175, 12555492, 12555534, 1635477, 1643532, 1643552, 1647135, 1S6648, 22568444, 22578315, 24575127, 24575160, 5744455, 8125531750

 

 

For the LUMINA 91-90

= 1/8"-27 = BorgWD 4087/4087P = AIRTEX 1S6592 = STANDARD PS236/PS236T = TRUE TECH RED PS236T

Alternate/OEM Part Number(s): #10096179, 10096199, 10201491, 10205410, 1643535, 1647136

 

 

Some Sample Ebay Listings for The Oil Pressure Switch showing Sizes & Compatibility:

 

 

On EBay regarding the 1/8-27 for a 1990 Lumina Euro 3.1/V6 - TrustBuilt Oil Pressure Switch

THIS LISTING SAYS THIS IS CORRECT PART/SIZE

http://www.ebay.com/itm/New-Oil-Pressure-Switch-S-10-BLAZER-S10-Pickup-Jimmy-Cutlass-S15-Chevy-Olds-/281052118863?pt=Motors_Car_Truck_Parts_Accessories&hash=item417002ff4f&vxp=mtr

 

 

On EBay regarding the 1/8-27 for a 1990 Lumina Euro 3.1/V6

THIS LISTING SAYS THIS IS THE CORRECT PART/SIZE

"Martins Oil Pressure Switch -- MARTINS OIL PRESSURE SWITCH -- 1/8 in. x 27 NPT

http://www.ebay.com/itm/New-Oil-Pressure-Switch-Chevy-Olds-S-10-BLAZER-S10-Pickup-Jimmy-Cutlass-S15-Auto-/230908230922?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c333fd0a&vxp=mtr

 

 

On EBay regarding the 1/4-18 for a 1990 Lumina Euro 3.1/V6

Will Not Fit 1990 Lumina Euro 3.1/V6

THIS LISTING SAYS THIS IS INCORRECT PART/SIZE

"Martins Oil Pressure Switch -- MARTINS OIL PRESSURE SWITCH -- 1/4 in. x 18 NPT

http://www.ebay.com/itm/New-Oil-Pressure-Switch-Chevy-Full-Size-Pickup-Suburban-SaVana-S10-Sedan-Car-/230908221586?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c333d892&vxp=mtr

 

 

Some Quotes:

 

 

"2.8/3.1 Oil Pressure Sending Unit w/ Gauge (Seems to be for any 60 degree W from 89-90): GM part number 10201491."

 

 

"1/4"- 18 thread."

 

 

"The 1/8" - 27 is for the 2.8L"

 

 

"original part numbers for a 90 lumina 3.1: switch: 25036940; sensor: 10201491

looking up 25036940 shows the 1/8 X 27 unit.

looking up 10201491 also shows the 1/8 X 27 unit."

 

 

I love doing this kind of research... you ought to see what I dug up about sway bar bushings... I suppose I could do the "take it out and look at it" strategy, but where would the Fun be in that? ...I'm going to go with the 1/8"-27... although I did find a listing for a BWD 4088 1/4-18 for $14 bucks, shipped... tempting but... RockAuto has the 1/8" for $16.86 shipped... I'll let you know how things turn out.

 

Ps. just want to share... yesterday, bought a 1964 Mercury Comet 404, 4 door Sedan, Straight 6/200 CID, Single Barrel Carb... Black w/Red Interior (new correct seat covers), All Original, 60K miles, new: tires, brakes, exhaust manifold, carb rebuild, tune-up, alternator upgrade... SOLID, CLEAN, No Rust whatsoever... beautiful, in and out, $4000... my wiffe needed a new commuter car... she looked at the usual, honda, toyota, subaru... borinnng... i said, "you only live once, get whatever you want, get something fun"... set out car hunting, first stop, this '64 Comet, about 2 miles from our home (my girl was born in '64 by the way)... the widow lady who owned it wanted $6K... we took a long test drive... FUN! ...offered $4K, no haggle, Kind Lady said "Ok"... she said she felt like it would be going to a good home that will care for and appreciate it.. boy was she ever right... can't wait to go to our first car show... missing a hubcap... if anyone's got one laying around, let me know... whatever you do... have FUN doing it!