Wanted : 1928 oil pump

[Vincent.vanGinneke]

I would not mind waiting half a year.
But a better option for me would be to first rework the Charles drawings in to metrics as I simply do not relate to Imperial sizes.
- now you could rightly quizz me about my 45+ year ownership of British bikes and still not grasping those Imperials... -
ehhh, back to the pump, who knows, I can then find an enthousiastic model engineer to make one for me !
Apart from the lathe and milling work it also needs two springs.
The larger one has it's own pages in Charlses book, but the small one.....
This smaller one has a tiny 'top hat' disc attached (?) to it.
Can one of you send a really close up picture ? I am interested in how this small disc is held to the spring .

[cmfalco]

This smaller one has a tiny 'top hat' disc attached (?) to it.
Can one of you send a really close up picture ?

Your wish is my command ... well, not your metric wish, for which electronic calculators have existed for a half-century to deal with. But, a short trip to the garage fulfilled your other wish (NB: these measurements were made on the abused oil pump that was given to me so I can't guarantee they would be identical to an as-new spring assembly):

The first photograph shows the overall assembly.

The next photograph shows the length of the spring.

The next photograph is a close-up of the cap, showing it holds the spring by having its edges rolled over to trap the wire.

The next photograph shows how I measured the thickness of the cap (after replacing the battery that had died since the last time I used this indicator).

And the final photograph shows all the dimensions needed to make one of these assemblies.

[Vincent.vanGinneke]

Hello Charles, no worries, I get around those measurements!
And that are really good pictures, it makes it clear how this small disc, wich is actually a cap, is fixed on the spring.
Thanks!

[MGriffin]

This smaller one has a tiny 'top hat' disc attached (?) to it.
Can one of you send a really close up picture ?

Your wish is my command ... well, not your metric wish, for which electronic calculators have existed for a half-century to deal with. But, a short trip to the garage fulfilled your other wish (NB: these measurements were made on the abused oil pump that was given to me so I can't guarantee they would be identical to an as-new spring assembly):

The first photograph shows the overall assembly.

Spring_small01.jpg

The next photograph shows the length of the spring.

Spring_small02.jpg

The next photograph is a close-up of the cap, showing it holds the spring by having its edges rolled over to trap the wire.

Spring_small03.jpg

The next photograph shows how I measured the thickness of the cap (after replacing the battery that had died since the last time I used this indicator).

Spring_small04.jpg

And the final photograph shows all the dimensions needed to make one of these assemblies.

Spring_small05.jpg

Many thanks for these pictures aswell. The last part i need to make. I have some conical springs as samples but as Vincent already mentioned its clear that valve is a cap rather than a disc.
Regards,
M

[cmfalco]

I have some conical springs as samples ...

My hasty drawing makes the spring appear conical, but the photograph shows it to be cylindrical. Although it appears to be progressively wound in the photograph, I suspect that's due to it being from an old, abused oil pump rather than the way it was made in the first place.

I mention in my book that I measured the spring constant of this smaller spring to be 3.2 oz./in., as well as describe how and why I heat treated the larger spring. The fact my spring lasted the 3000 miles of the Cannonball argues for heat treating these springs the same way I did.

The only job the cap has is to block a small hole on the upstroke of the piston. If I were to make one, I would be tempted to use a soft metal like annealed Cu, since it would be easier than steel shim stock to form into a shape to capture the spring.

[cmfalco]

I realized I hadn't shown the dimensions of the plug at the end of the oil pump housing so, even though this thread is hidden in the 'Wanted' section of the forum where no one will ever find it again, the composite shows the plug with and without the spring on the end.

The drawing gives the dimensions.

[Karol Burger]

I will probably have one pump for you, my friend found one in his shed. he should bring it to the Czech Rally

[Vincent.vanGinneke]

Hello Karol, thats really nice ! are the '27 and '28 pump the same?
This looks like a '27 timingcase.
Does the pump have the two springs inside ?
Herman Noort -he who will bring you the Cheval de Fer stickers- is the man who can take in home.

[nevhunter]

I'd heard plenty about this pump over the years. (Not all good) Thanks all for the information provided Here It should be easy enough to make one work reliably. Nev

[nevhunter]

I'd heard plenty about this pump over the years. (Not all good) Thanks all for the information provided Here It should be easy enough to make one work reliably. Nev