Subject: Magneto Difficulties
I thought this may be of interest to anyone who has bought a non runner or a dismantled car and having put it back together it does not run properly.
The engine on my 11.9, which was last started in 1989, and now fully rebuilt, simply would not run correctly. It would start and with a bit of coaxing it could be driven but not without, after a short time, spitting back and stalling.
All the usual issues were addressed, Zenith carb cleaned out and properly set up, valve and magneto timing checked, period fuel filter fitted, even the magneto sent away to be checked and found to be sound.
Eventually I called in a man who can, and he immediately diagnosed ignition issues. The magneto was stripped down and it was found that whilst it was fully functional the contact breaker base plate had at some time in the past (probably in the early 1970s) been swapped to one stamped with an 'L' This relates to the position of the cam (left) that opens the points and affects the position of the advance and retard. The result of the cam being in the wrong place was a magneto that could not be properly advanced. Even though the advance and retard lever looked to be moving the contact breaker housing normally, with the cam in the wrong position nothing was moving within and the magneto was always fully retarded, hence the problems.
The solution was to borrow a points base plate from my 2 Litre Magneto which was stamped R (right). The result was an engine that started on a quarter turn of the handle, ran smoothly and pulls really well on the road.
Only problem I now have is that I am seeking a contact breaker base plate stamped R that will fit a Simms SR4L magneto. Any ideas or leads?
Regards
Mark
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times. Last edit on Aug 04, 2016 5:22 pm by Mark.