Author Topic: Drawings for non-return oil valve, Models CO, 600EW, F28, 350EW  (Read 11016 times)

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Offline Doug

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Here are the drawings for the non-return oil valve as screwed into the front cylinder on certain models. Two versions are shown, which except for the lower housing, share identical parts. One uses a 7/16-20 thread, and is as used on the OC, 600EW, F28, and probably other Douglas big twins of the era. The 350 EW needed a special lower housing to clear the adjacent cylinder hold down nut, and smaller, shorter thread to cope with the thinner cylinder wall found on the 350cc barrels. Apparently this is the same as used on the 2-3/4hp models.

Below each is a link to a PDF version (Requires Adobe Acrobat) that you may find easier to print.

Downloadable PDF file

Downloadable PDF file


02Jul10  Fix typo, add reference to 2-3/4hp models. -Doug
« Last Edit: 02 Jul 2010 at 23:43 by Doug »

Offline Petethesign

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Thanks Doug
Exactly what I needed.

Offline Neilj

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Thanks looks complicated going to have to find a good machine shop