Ignition timing

I have a Norman t300 with a BTH magneto that wasnt turning so stripped and cleaned it, question is the drive end isnt keyed. How do i time it ? Having never worked with a magneto before im thinking i just bolt it on and turn points carrier! How do i get it on the correct cylinder ? Hope someone out there has done one before

Its been years since I did one of them, Something like pull the front cover and set the timing to TDC and set the mag to its firing point BTDC, I haven't got a clue what that is at the moment.

Odd. My T300 has two drive pins. See first picture in my thread:

https://ukengineforum.forumotion.com/t9440-another-norman-t300?highlight=norman

I have a war time servicing guide which may be useful. PM me with email address if you would like a copy.

if you stripped the magneto you will have seen that the points carrier is keyed and cannot be turned once secured.

BTH magneto only:
start with the magneto coupling free to rotate on the taper
put the flexible disc on the coupling and place the mag on the mag platform with the flexible disc inserted in the drive coupling on the engine
remove the valve spring cover from the LH cylinder (viewed from the starting handle)
turn the flywheel clockwise until the LH side inlet valve is closed and the IGN mark is at TDC
remove the contact breaker cover from the magneto
turn the points holder until the heel is just touching the LH side cam and the contacts are about to open
carefully remove the magneto and make sure the magneto coupling and magneto shaft does not move while doing this
tighten the nut to secure the coupling to the magneto taper shaft
replace the magneto on the platform and bolt in place
replace the contact breaker cover and LH valve cover

check points open at with IGN at TDC on the flywheel
if not repeat as abve

Thankyou everyone

Think ive got the timing quite close, but the screw on the outside of the points carrier is a bit confusing. It has two tiny cut-outs (one either side) how do i slacken it off to adjust/fine tune points opening position. Being careful as i dont want to damage it. Any suggestions gratefully accepted . Cheers Mark

Could you post a photo of the screw head?, from your description it sounds like you need one of these bits...



Apologies for the image, first one grabbed off the interweb.

And theres a small hole in it