Author Topic: Mark 5 engine timing gears  (Read 652 times)

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Offline phil1

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Mark 5 engine timing gears
« on: 02 Nov 2017 at 17:09 »
Hi I am  very interested in the Douglas article (see here) as I am trying to gather as much info as possible to help with the complete restoration I am attempting on a Mark V. I am particularly interested in the dreaded valve timing marks at the moment as my cam wheels appear to be very different, in that they are considerably dished out with unusual markings. On a brighter note I have just had the crank shaft re-conditioned by Alpha Bearings so I feel that some progress is being made. However further down the line I will have to attend to some damage to the cylinder head where there is damage to the top edge. Regards Phil 1.

[Post moved to General Discussion and link created to referenced post. 02Nov17. -Doug, Site Moderator]
« Last Edit: 02 Nov 2017 at 20:43 by Doug »

Offline eddie

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Re: Mark 5 engine timing gears
« Reply #1 on: 02 Nov 2017 at 18:21 »
       The timing gears on the Mark 3 - 5 machines had plain sides. The earlier T35 mk1 machines had gears with recessed sides but the teeth were larger , being 12DP whereas the later gears are 18DP. If your engine has 18DP gears with recessed sides, the gears are most likely from the wartime generator engine.


Offline tck

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Re: Mark 5 engine timing gears
« Reply #2 on: 04 Nov 2017 at 07:40 »
I have timed a few engines without timing marks and setting both valves equally open at around 4 degrees before TDC is often the best approximation certainly I have raced a Vincent so timed with better performance than the standard route