General => Douglas Motorcycles - General Discussion => Topic started by: Roys rider on 13 Nov 2018 at 11:10

Title: D/f engine tight
Post by: Roys rider on 13 Nov 2018 at 11:10
Hi All,
I have an engine problem. I have stripped and rebuilt a few engines however I have never previously built one from parts. The D/f I have put together wont turn over on the kickstarter. Eddie suggested that it might be the split pin on the clutch nut however cutting the excess off didn't solve the problem. I know it's not a good idea but if I jump on the kickstart it just moves a mm. It is now out of the frame and I have removed the alternator to get at the nut on the crankshaft which turns fine with a 1 ft spanner so roughly the same as the k'start. It is the same with or without the gearbox. It was suggested at a club meeting (many years ago) to just put it together however should I have allowed for some end float and if so which end and how much and 'basically' how? or is it something else? Anyone any ideas? I'm at the NE end of Cheshire.
Look forward to hearing from you.  Peter
Title: Re: D/f engine tight
Post by: eddie on 13 Nov 2018 at 11:50
          First of all - please dont jump on the kickstart - it is the weak point on the Dragonfly engine/gearbox unit, and you could end up wrecking the gearbox case.
 From your comments, I think you may already have located the problem - with the generator cover removed, the crank turns OK (with or without the gearbox attached) - so the problem is likely to be within the timing chest. First thing to check is the crankshaft nut - this should be a thin nut (like a locknut) - a standard nut is thick enough to foul the crankshaft outrigger bush in the generator cover. Check carefully that there is some clearance between the nut and the bush - due to the direction of rotation, if it does drag on the bush, it could get unscrewed and jack the generator cover off the timing cover.

Title: Re: D/f engine tight
Post by: Roys rider on 13 Nov 2018 at 17:06
Sorry I should have added something extra. Putting a short spanner on one of the clutch bolts will also turn the engine. This was done before I removed the alternator. The nut on the stator is a thin one. It is a very long time since I put this engine together and I may have learned some things since then so am thinking of removing the barrels to make sure all is well in there. Anything special i should look for?