Reilang Oil Can Nozzle Thread

I have several Reilang oilers, but need to extend the delivery tube on one, to be able to reach the middle big end on my 7 1/4" gauge A3. Does anyone know what the size and pitch of the screw-on nozzle is, please? I have established several that it is not, in particular, it's not metric (M4.5 would be the right size but the pitch is coarser than .75mm) and I don't think it's BA. Given the age of the design, might it be BSP?

The smallest BSP thread is 1/16" with an OD of over 7mm, so it might not be in that series.

There is a picture of spare parts for one model of can here:

https://www.ajreeves.com/12461.html

Please confirm it is the part bottom left of the picture.

Have you any known bolts that you can use as a thread gauge to judge the pitch? How have you determined it is coarser than 0.75mm pitch? What is the actual OD of the thread?

Cut the end off the delivery tube at the bottom of the internal threads and thread it a known, suitable internal thread (you are extending it, so just extend it 10mm more). Turn down the nozzle, soft solder on a plain sleeve and apply male threads to match the new internal ones.

Checked mine.

Thread OD 4.4mm dia thread, 0.8mm pitch (using pitch guage) Hex on spout 6mm A/F

V. close to 3/16" BSF; 4.7mm x 0.79mm.

3/16" BSF plug tap does not fit tube internal thread Too large OD

Would you care to speculate whether the tube has enough thickness of body to enable its internal thread to be enlarged to M5?

The male thread on the nozzle would be easy to enlarge.

The brass tube is 6mm OD. If I was going to tap M5, I would certainly use a Spiral Flute tap because the swarf would cut and clear more easily.

More simply make a suitable length brass rod extender, bored through at say 2mm for the oilway and counter bored each end 6mm, soft/hard solder in place.

A standard M4.5 x 0.75mm tap fits the tube on mine nicely.

Thank you all very much indeed for your comments, measurements, etc. To Andrew Moyes, maybe so, but I tried a M4.5 x 0.75mm die on the nozzle itself and it jammed after half a turn. That's what made me say at the outset that I didn't believe it was M4.5 x 0.75mm. At my club today (Bank Holiday Sunday so we were public running all day - I was able to demonstrate what I need to reach) a very wise experienced colleague looked at me astonished and said " Why bother? Just cut the tube in half and silver solder the two resulting halves into an extension tube of the same bore as the outside of the two halves - don't need to mess with threads then!" This is in effect a simple version of what KWIL suggested in the last post above and I must admit, left me thinking: "Why didn't I think of that ??", so that is what I am going to do. Thank you all again for your efforts and interest, but, problem now solved, albeit by a method other than the one which prompted me to pose the question in the first place!

Howard, glad to hear that you have a solution to your problem, but if anybody wanted to continue reading :-

Reilang threads

That thread is about the size of thread where the spout connects to the top of the can not the smaller nozzle thread