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Dave

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timing

Started by jyprfc, 26 Nov 2013 at 22:26

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jyprfc

hi can anyone tell me how to time a mk5   jim

David Lawrence

Hi Jim,
I am sure somebody will give you tips of how to time the mark engine, however if you do not have a copy of the mark maintenance manual, which does contain a fair description of the procedure the Douglas Club can supply you with a copy.
If you are interested please email me directly on the site email and I can arrange a copy to be sent to you. Incidently we also have copies of the parts manual.
Dave

eddie

Jim,
       If you are referring to the valve timing, there are timing marks on all the pinions. With the pistons at TDC, you should be able to align the marks. However, you will find the idler has an odd number of teeth, so the marks only line up now and again. The easiest way is to remove the outrigger plate and remesh the idler. You should end up with the valves just 'rocking' with the piston at TDC. (i.e. exhaust just closing as the inlet starts to open).
     To time the magneto - bring the pistons to TDC and with a rod in the spark plug hole, check the depth to the piston and then add 7mm, then turn the engine backwards and then bring the pistons up again until they just contact the rod at the new mark. Check which cylinder has a valve open and time the mag for the other cylinder. On the Mark series engines, it is possible to remove and fit the mag complete with the timing gear, providing you remove the offside clamp stud to allow the mag to slide back. Also, remember that on these engines the crank and mag rotate anti clockwise looking from the back. The figure of 7mm before TDC is calculated from the 36 degrees quoted in the handbook printed in 1950, so, with the modern 'improvements???' in fuel technology, you may need to adjust the timing on the advance/retard to find the best setting.

   Regards,
                  Eddie.

jyprfc

hi eddie  can i remove points plate without disturbing timing  jim

eddie

Yes Jim,
             The points plate assembly is retained by the centre screw. With the screw undone, you may have to wriggle it about to release the brass points plate from the taper. The taper should have a key formed by pushing up a blade of the brass - make sure this has not been pushed flat again by previous poor fitting. Careful replacement of the points plate so that it locates on the key will ensure that the timing is not altered.
  Regards,
                Eddie.

jyprfc

hi thank you for your help  jim