Oil press sensor thread..?

-
French demon

French demon

Well-Known Member
Joined
Jul 12, 2020
Messages
761
Reaction score
864
Location
South of France
Hi guys
I consider adding an oil pressure gauge to my dashboard but I don't know the thread needed for the engine sensor.
I found for sale some sensors with 1/8NPT or 1/8-27NPTF thread. Will it fit my slant-6?

1/8NPT sensor on Amazon

:thankyou:
 
Both are pipe threads, NPT= National Pipe Thread NPTF= National Pipe Thread Fuel. Both will work same threads, but NPTF will have longer threads. This is usually use in fuel systems for a tight fit without the use of sealants or tape. I would use the 1/8 NPF sender but if the threads are wallowed out this where the NPTF sender would be a big help......
 
Thanks Dicer.
I don't think that the threads are wallowed out as my current sender is original and probably never disassembled from the engine.
So, a 1/8NPT threaded unit will fit my engine?

I have another question : I saw that some sending units have two electrical terminals. I suppose that these units are intended to send information in parallel to both an idiot light and a pressure gauge. Is it correct?
 
Last edited:
No that is not usually correct, depending on application. The link that you provided shows a one wire sender, that is the one I would choose. I would do a search OR visit your local parts store, and get a gauge/ sender kit. This will insure you that you will get a sender and oil pressure gauge that are calibrated together.
 
I will go for a gauge/sender kit, but I was asking for the twin terminals because I would like to add a pressure gauge, but also keep my OEM warning light.
I will make some researches on internet to find the adequat kit (thanks to you, now I know the sender threads size) :)

:thankyou:
François
 
Senders for the most part are an on/off switch for dash light. Senders made for gauges are a variable type resistance, I have yet to see a oil pressure sender that will do both, IF YOU want to plumb a tee into the block and have both senders, that is a lot of work.... but doable.
 
Seemingly, twin-terminals sender units can operate at the same time the warning light and a pressure gauge.
Here's a schema I found on internet today :
schéma montage double.jpg

G/WK twin terminals sensor unit
 
No, no, I'm looking for the answers

But you gave me the main one : the sender threads size :) Thanks again.
 
IIRC, the slant 6 engine used an adaptor when the car was equipped with an oil gauge. The slant 6 light sender threads are huge, so, you had to have an adaptor to neck it down to the standard gauge sender that they used on all the V8 cars. The '72 up trucks (and maybe the earlier ones too, I forget) used a similar one, but, it was a 100 PSI sender whereas the cars had an 80 PSI one.
 
If you're adding an aftermarket gauge, I'd use whatever the manufacturer recommends and adapt the plumbing as needed. You may want to place a wanted ad here on FABO for the factory adaptor. The '66-9 slant 6 Barracudas would have had one. Probably some other models too.
 
Hi Cudamark,
If I understand well, the light sender threads are NOT 1/8npt and an adaptor is needed?

I found this old post on FABO :
mcnoople said:
My memory from when I last added a mechanical guage to a slant(1999?) was that the oil pump outlet threads are 3/8" npt and most common pressure senders use 1/8" npt.
Click to expand...

So.... 1/8NPT or 3/8NPT oil pump outlet threads on the slant?
 
Yes, the sender hole on the oil pump is not 1/8 NPT. it needs an adapter.
 
The oil sending unit on the slant 6 installs directly on the oil pump and has 3/8" NPT threads. Here's what it looks like.
OIL SENDER.jpg
 
VDO has an extensive catalog but their website is hard to navigate. I had a gauge but no sending unit. I reached out to them for guidance and they got back to me quickly with an appropriate match.
 
CAVEAT!!! In this day and age you must be aware and careful of OVERSEAS pipe thread. EG the pipe thread for Japanese cars is slightly smaller than U.S. It just depends on how deep the US thread was tapped. Some Jap senders will screw in deep and never seal, others will "get by." BUT IT IS NOT the same as US. I'm pretty sure such as German stuff is different as well, but I don't know about other countries in Europe. "It ain't the same."

Ebay stuff is REALLY bad for not being "true."
 
67Dart273 said:
CAVEAT!!! In this day and age you must be aware and careful of OVERSEAS pipe thread. EG the pipe thread for Japanese cars is slightly smaller than U.S. It just depends on how deep the US thread was tapped. Some Jap senders will screw in deep and never seal, others will "get by." BUT IT IS NOT the same as US. I'm pretty sure such as German stuff is different as well, but I don't know about other countries in Europe. "It ain't the same."

Ebay stuff is REALLY bad for not being "true."
Click to expand...

In Europe, usually, threads are metric. But US threads are also available.
I easily found out locally a 3/8npt -> 1/8npt adapter.

3-8npt to 1-8npt.jpg
 
You must log in or register to reply here.
-

Back
Top