Rhythm Thief wrote:
Sean wrote:
yup ken has been advocating those for ages - and having used Smyth602 one today can only add to the recommendation! looks like a toy , priced like a toy but bloody good value and works an absolute treat no excuses for setting the timing statically anymore. ( and remember the light is not to check the static mark on the flywheel at tickover! >stern look<)
Without wishing to appear an idiot, what am I looking for when I eventually come to connect mine up to the Dyane? It was supposed to come with instructions but it didn't. What are the general principles of usiong a timing light?
well as ive got a weeks worth of ironing to get through itll have to wait
oh ok then
you need to have some markings on the engine so you can set the timing - most cars have some sort of mark on the crank pulley and a degree scale or marks for important settings - our cars dont we have the static point where you put a peg in the hole and set the timing. so using this and the handy increments on the flywheel we can mark the timing. the 360* of the crank rotation can be divided by the teeth on the flywheel as they are a useful reference (360* divided by 107 teeth = 3.36 so each tooth that passes is 3.3* of crank rotation) we need a known fixed point there is no TDC on these cars only 8* we need a second point to show where max advance should be and an ideal max advance. 32* is a good safe max advance for an aircooled engine of that sort of compression ratio. so that's a further 24* from static or 7 teeth as teeth are our measuring scale
right the practicality bit
peg the flywheel mark the tooth that's under the engine /gearbox stud left( as you peer in the engine bay) of the starter nose -mark the casing opposite the tooth so that they line up thats the "datum" now pulling the teeth from under the starter with a screw driver count round 7,and mark it then go back to the static point and do it again and once your sure you are correct mark that 7th tooth
Connect the black and red crocodile clips up to the battery terminals clip the black clip over either HT lead. start the engine and point the gun at the Datum and pull the trigger. At idle the static mark will be to the left of datum (BECAUSE ITS THE STATIC MARK! and the engine is NO LONGRER STATIC!) it un important where it is. Now gently raise the revs as you do the static mark moves left into the bellhousing and the 7th tooth comes in to view from under the starter - it should go no further than the datum on the stud, adjust the points box till it does so. dont rev the nuts off it - only till the marks stop moving.
DONE! its actually really simple despite me prevaricating and avoiding the ironing board that has been placed beside me
