maxpesce

what size threads are on the OIL PRESSURE sender (on an fd) I need to get an adapter to install my mech 0-150psi Oil Pressure guage

R Xplicit

yeah me too....i have had an electrical one for some time, and bought a t fitting from napa. i am going to get in there soon...


louis

duboisr

It is a pipe thread just take the unit to the store with you to get it matched up. Only one car ? Take it off in the parking lot.

maxpesce

So you are telling me the OEM sender uses an NPT thread? if true then I don't need an adapter as the guage already comes with 1/8 & 1/4 NPT fittings.

If this is not correct then what metric threads are on the OEM sender?

tfhuth

I have not had mine out yet, but I find it very hard to believe that its an SAE thread. That sucker has to be metric. Tom

duboisr

If it is metric let us know , none of the metric thread gage blades fit the threads that go in to the block but a 27 tpi sae blade fits .A 1/8 pipe 27 tpi tap goes right in with no force, the tap matches the threads on the senser as well. Garfinkle told me pipe , please let me know so I can call him stupid one time.

Bacon

iTrader: (12)

i heard something liek this a while ago so i dont know if its bs or not but i remember some one saying the sender threads in the block were BPT (british pipe thread or something like that) never checked into it but i remember that

poss

iTrader: (5)

1/8 BSP tapered

courtesy of db2boy

duboisr

So it is a pipe thread thanks for the info,

tfhuth

The reply above yours, says 1/8 BSP; that's different than a 1/8 NPT. Some people refer to BSP's as 'metric'.
Tom

Actually I think the standard is BSPP. Crossing threads gets VERY confusing, no pun intended.

maxpesce

I believe Male NPT will fit into Female BSP because the thread diameter pitch and shape are almost identical but because the taper is different male BSP (BSP has less or no taper) does not fit well into Female NPT. METRIC (MPT?) threads have NO taper and the DIAMETER, PITCH, and SHAPE are completly different.
Thanks for the info - 1/8"-27tpi NPT or BSP port means I DON'T need an adapter!

tfhuth

Max,

I'd hate to see you start leaking oil. If you say they're close enough to each other to create a good seal; ok. I have the 1/8 NPT specs in front of me, the pitch is .03704" I can try and find the BSPP standard if you want, it should be around here somewhere. If you're going to use the 1/8 NPT in there make sure you use some good thread sealant. Good luck Tom

maxpesce

It will get wrapped w/ teflon tape so should seal well.
and yes i would like to see the diff in the specs NPT vs BSPP
TIA
Mark

darkside7

iTrader: (12)

just buy the greddy adaptor that firs between the engin and the oil filter. makes insatll a lot easier. pluse you have enough spot for tem sensor as well

maxpesce

It is an Autometer Guage, not GReddy. Autometer guages all use 1/8"NPT or 1/4"NPT thread. GReddy Guages are most likely M10 or M12 (I'm gussing.)

tfhuth

Ok Max,

The BSPP is 1/8 - 28 tpi and has NO taper it has a parallel thread. I'm looking for a BSPT now. Tom

tfhuth

Well, that's it, gotta go. No good info on a british taper thread. Let me know what you find out. Tom

maxpesce

I will be working on the install tomorrow so will post definative answer later.

maxpesce

I stopped in at MARIAH on Friday and got the info I needed, the PORT on the Engine is 28tpi ( not sure if it is BSPT? or Metric?) and tapered - The Nipple on the SENDER is 27tpi NPT. MAZDA uses an ADAPTER 27tpi female > 28tpi male that is already on the OEM sender, so no additional adapter is required. My guess is that MAZDA shares OEM suppliers with FORD for the senders hence the NPT (US) threads.

tfhuth

Max,

Wonderful information thanks!! So then you bought an adapter? Take care, Tom

maxpesce

UPDATE:

Finally got around to doing the Oil Press Gauge instal on Monday (5.26.03) and discovered that indeed the Block is threaded 1/8-28tpi BSP
and so is the STOCK sender, the stock "Adapter" is just a spacer so the sender will clear the oil filter pedestal. My install required a 1/8-28 BSP male to 1/8-27 NPT female adapter. I got mine from Pep Boys, it was included in a SunPro metric adapter kit.

I also determined that a 1/8-28 BSP male fitting will screw into 1/8-27 NPT female fitting b/k the BSB is slightly smaller in dia. but will bottom out in the taper before the thread interferance becomes excessive. a 1/8-27 NPT male fitting WON'T go into 1/8-27 Female b/k it is just too big (unless the taper is cut too far thus reducing its initial dia.) Also BSP threads apear to have little or no taper to them.

rousu

Is there a thread that tells how easy it is to remove and replace the oil pressure sender?
Or should I read the manual...

(rtms)

Kento

Easiest method is to jack the front of the car up (or use ramps, like I did), and get at it from underneath. I forget what size wrench you'll need, but it's fairly straightforward once you gain access to it.

maxpesce

I did mine from the top - No problem - the stock sender has a large hex on it (1 1/4" iirc) and just 1 wire to disconnect. Assemble all the spacers/ adapters first, then screw the whole mess back into the block and last conect the new capilary tube (for mech gauge) or sender.

rousu

Chickened out; had the mechanic replace it.
Looked easy enough to do oneself, with a little patience, from above the car.
Maybe easier with a 30mm socket, but wrench would do.
Catch the lost oil so you don't banana.
OEM replacement just screws in, and attach wire.
Some blind careful thread starting so don't cross-thread; hands will be in there a while so do when engine is not hot.

No occasions of indicating zero oil pressure since the sender was replaced.