vokes oil filters

[geoffshobbies]

In Page 5 of the Mark series guide by John Holmes there is reference to VOKES OIL FILTER JPG.
Can anyone tell me how to access this?
A interested to know how filter is fitted on post war m/c s.

[eddie]

The Vokes Oil Filter was an optional extra. It was mounted behind the RH cylinder on a steel pate that fitted on the upper and middle barrel studs. The awkward bit is drilling the front crankcase half for an extra pipe fitting so that the oil can be rerouted through external oil pipes via the filter before returning to the original vertical drilling that goes up to the front main bearing. Also, to complete the conversion, a blank has to be inserted in the original oil gallery to prevent oil bypassing the filter.
  Unless you already have one of these filters, it is unlikely that you will find one - they were not very common! When we were involved with the LDMCC spares, we contacted Vokes in the hope they may be able to supply some filter elements - they eventually rang back to say they couldn't find any reference to their filters on a Douglas!

   Regards,
                Eddie.

[Dave]

In Page 5 of the Mark series guide by John Holmes there is reference to VOKES OIL FILTER JPG.
Can anyone tell me how to access this?

I checked our files looking for this image but couldn't find any trace of it. I don't think it was included with the original manual we received back in 2007. Doug may know more regarding the updated version from 2013.

Dave

[Doug]

The post for John Holmes' "Mark Series Maintenance Guide" is here:

https://www.douglasmotorcycles.net/index.php?topic=1864.msg6725#msg6725

And a direct link to the current latest edition (2012) PDF is here:

https://www.douglasmotorcycles.net/aa-files/documents/2016/Mark-Series-Maintenance-Guide-2012.pdf

The images are a the end of the document. The one for the Volkes oil filter is on page 40. Note this direct link will not update if a new version is posted.

-Doug

[Jonathan Hewitt]

Vokes oil filter as fitted to the Mark series.
Posted after a discussion at the LDMCC 
do last weekend.
  Have fun
    Jonathan 

[eddie]

The Vokes oil filter is not just an 'add on' accessory. Fitting it involves dismantling the engine to carry out modifications to the oilways in the front half of the crankcase. An extra oilway has to be drilled in the bottom of the case, and then the original oilway has to be blanked off.
  Anyone running a bike that has a filter fitted, and wants to remove it, will need to make up a short connecting pipe to go between the 2 ports in the bottom of the crankcase (in order to bypass the plug fitted in the oilway).

Regards,
             Eddie.