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1/8 NPT sensot in a 1/8 BPT hole
bi22le - 9/10/18 at 09:58 PM

I am replacing done of my sensors as I switch to the digidash and this problem is not documented on this site, yet!

As per title. I have a 1/8 NPT from ETB and A1/8 BPT ( I think) on my Toyota engine. The guy at ETB could not offer much support but said they are so close, and tapered, then either wind it in a good few turns anyway or tap it out.

What do you guys think?

I'm going to give RAW a call tomorrow and see what they say.


JonBowden - 9/10/18 at 10:22 PM

I take it that this is to go in a 4AGE we her the pressure switch normally goes?
I used one of these from eBay
https://www.ebay.co.uk/itm/BSP-NPT-Adapters-Male-BSPT-to-Female-NPT-Exten-in-Brass-European-to-American-/121411882514?var=&hash=item0
[Edited on 9/10/18 by JonBowden]


voucht - 10/10/18 at 05:52 AM

quote:
Originally posted by bi22le
I am replacing done of my sensors as I switch to the digidash and this problem is not documented on this site, yet!

As per title. I have a 1/8 NPT from ETB and A1/8 BPT ( I think) on my Toyota engine. The guy at ETB could not offer much support but said they are so close, and tapered, then either wind it in a good few turns anyway or tap it out.

What do you guys think?

I'm going to give RAW a call tomorrow and see what they say.


Hi,
I think by BPT your mean BSPT, which is a BSP thread, but tapered (conical)?
No, they are not close with 1/8 NPT. One has 28 threads/inch, the other has 27 threads/inch. And diameters are quite different too.
So my advise would be that you do not fit your 1/8 NPT sender in your 1/8 BSPT hole, you will just damage both.
Try to find a male 1/8NPT to female 1/8 BSPT adapter, or a BSPT sender.
Hope that will help
Good luck!


scimjim - 10/10/18 at 06:38 AM

1/8 BSPT and NPT are very close (one TPI difference and about half a millimetre diameter) IF it’s a high quality piece, so it will probably fit in quite easily.

The main problem is the thread shape - NPT is 60 deg with sharp teeth, BSPT is 55 deg with rounded teeth - so it would need lots of thread sealer to have any chance of sealing.

I’d buy an adaptor


bi22le - 10/10/18 at 11:54 AM

The oil temp should be fine for an adapter, but I don't think I have much space for the water temp.

I could put an inline housing, if they exist, and cut a silicon tube.

Any other thoughts?

[Edited on 10/10/18 by bi22le]


Mr Whippy - 10/10/18 at 12:00 PM

plenty of PTFE tape...


Angel Acevedo - 10/10/18 at 12:54 PM

Do you have space for a tee?
If so, could you fit something like this:http://www.mtixtl.com/t-piecewithmale18nptandfemale18bsppfittingconnectoreq-tp-18bspp.aspx

Failing that, You could get a 1/4" X 1/8" X 1/8" Tee, modify the thread on the 1/4" branch and install the sensor on the 1/8" Branches.
HTH


Angel Acevedo - 10/10/18 at 01:16 PM

Incredible what you can do while doing nothing...
See what I found while waiting for the post to open...
https://acuityinstruments.com/products/bspt-to-npt-oil-cube
Not cheap though....


907 - 10/10/18 at 03:52 PM

TIG weld (or get someone to do it ) half a nipple to half a socket.

You will then have a male to female adapter.


Schrodinger - 10/10/18 at 04:27 PM

Is this what you need?
https://www.merlinmotorsport.co.uk/p/oil-pressure-gauge-t-piece-1-8bspt-tp-1-8bspt?utm_source=Google&utm_medium=ShoppingUK&utm_campaign=Shoppi ngUK&vat=on&currency=GBP&gclid=EAIaIQobChMIjKrQ66T83QIVAeJ3Ch1nmQqBEAQYBCABEgK0TvD_BwE


indykid - 11/10/18 at 12:59 PM

quote:
Originally posted by 907
TIG weld (or get someone to do it ) half a nipple to half a socket.

You will then have a male to female adapter.


Ideal if you have the nipple and socket...and a tig welder (and it's undoubtedly what I'd do) but for £3.80 posted, I'd be sorely tempted to go for the brass one!

Good way to make a 90/135° adaptor though...

[Edited on 11/10/18 by indykid]


stevebubs - 11/10/18 at 03:30 PM

For plumbing, Think is generally my first stop..

https://www.thinkauto.com/acatalog/On_line_shop_Various_178.html


stevebubs - 11/10/18 at 03:31 PM

MFS10-3-3 should do the job, I think - worth calling to ask


stevebubs - 11/10/18 at 03:34 PM

also https://www.amazon.co.uk/dp/B01JZX6H9U/ref=psdc_1939465031_t1_B00FXSSUH4