ew oil pump

[kev]

 my oil pump is ready to go...I think...

I have made my gear out of brass...as I cant get a fixture solid enough to cut one from steel...may have to have a rethink on that one...

I made this one from brass the areas of contact on lifting are about twice as wide...  the gear is full contact the original douglas design has only pinpoint contacat

this 10 pitch worm also cut 26 teeth...and I understand the originals are 20 and 24??
I have also made the acting pin as a sleeve over an allen bolt...so the pin rolls as it climbs and drops

anyway..this one will get this thing going and I,ll keep an eye on it....and keep working on a way to cut that helix pinion...out of steel...

today
   I just need to know if I have all the parts to my pump..???  I have the very fine spring that goes on top of the little top hat bit...  is there some sort of valve that goes in the bottom..in the pickup casting??

[kev]

  my timing cover....

it looks like someone has cut a little ditch for the oil to follow...

should this be welded, or epoxied up..???  or is this a bona fide improvement

the motor should turn clockwise looking from the timing side...
what holds the worm nut on...I reckon it should be left hand thread??..

there is a bunch worn out of my timing cover where the original has come off the crank...

I have made my worm gear longer than the original to get a bit better purchase on the pump pinion... I should be able to make an insert to fit over the oil quill...and have an oil seal inside....
but...the worm...what keeps it from unscrewing???

[Doug]

The hand-cut groove is I think a mistake on someone's part.

Even when converted from the early gear type the later reciprocating type oil pump the groove does not need to extend to the 'hole'. One the early type this increases the chance of leakage past the end of the gear. On the later type it would be disastrous as it would connect the first and second stages of the pump. In both cases, the groove is only extended a short distance to provide the intake path for the oil to the crankshaft quill.

Presumably you reviewed this post? It shows both types of timing cover and the components of the reciprocating pump:

https://www.douglasmotorcycles.net/index.php?topic=1002.msg3305#msg3305

-Doug


[fix typos.  -Doug  02May16]

[kev]

  Doug

thanks heaps for your help and enthusiasm..

I have worked thru that post of yours...was a big help..

if that is all the parts there are...then that is done....was wondering if there was some sort of disc under the spring in the pickup??

the springs I have are different to what is in the pictures...I know they may have been substituted dozens of times over the last 80 years..and springs just don't last that long

soooooo  the groove in the timing cover...I,ll either weld of epoxy closed...as the earlier post shows..

[Doug]

No disk, the fairly heavy spring returns the plunger to the beginning of its stroke (up). There is a lighter spring and ball inside the plunger piston that acts as a non-return valve.

-Doug

[kev]

  doug...
wow ..learned one more thing...the ball and spring inside the piston rod??...is that serviceable??  obviously I can blow and suck...???
  any tips on making sure it is working??

[kev]

 doug

  I had a good look...aannnnnnd yes there is a ball up inside the plunger rod...

         now...the ball is just above the threads for the acting pin..and wont drop below...and definitely no spring in there

  thought I,d check before I work on this thing...  I would think the ball should drop to the bottom of the inside of the plunger??
  I may be able to sharpen a drill bit shank enough to scrape the inside of the hole to release the ball....???

  is there any other solution??  the spring??  is it needed...    couldn't see any way to get down the hole from the top hat end....
any thoughts???