First, the bolt head is not 11mm across flats, it is 14mm. If it is not, it has been changed. It was certainly 14mm when I had the car Anders.
Thanks, then it's still 14 mm, as I haven't touched it before. The reason I thought it was 11 is that I have a spare cam sprocket cover, which I got with some parts off ebay some time ago, and the bolt on that is an M7 with 11 mm head. Obviously it has been changed.
Second, I have answered this one before on this forum somewhere I'm sure.
Now that I think about it, I think you have explained it to me in a private e-mail earlier on. I'm afraid I didn't check my archive before posting.
Anyway, the easiest way is with a 4-way high angle spanner. This is a short open-ended spanner with the openings at higher angles than normal to the main body of the spanner. Normally they are 15 degrees. The high angle spanner has them at 30 degrees one end and 60 degrees the other. By turning the spanner over you get a choice of four positions.
I have had two of these spanners in my tool kit for years for specific jobs. A half inch one for older English vehicles when we were still using UNF/UNC sizes; and a 14mm one for certain metric jobs including the Murena distributor bolt. Mine are Snap-on but there are others.
That sounds like a good tool to have.
The other option is to make one up purposely for the job. You cannot get a normal ring spanner in there, but you could grind one down just enough to slip in, and then bend the body of the spanner up to clear the surroundings.
I have a habit of saving the tools that come with IKEA furniture, bikes and the like, so I've got a few pieces of metal in my workshop that I think I can make something out of. One of them in particular, looks promising. If not, the ground down ring spanner sounds like a good solution.
It's not easy to get in there but normally you only have to set it up once, and if you then carefully mark the flange as well (so you can see if it has moved or to align it if the distributor has been out) it makes things easy for the future.
Mine (as you have suggested earlier) has several markings. I took a photo a few days ago to make sure I could align it back correctly:
http://gallery.dinsen.net/v/biler/Murena/technical/dizzy/DSC_1397.JPG.htmlI agree, that advance is best left at 10 degrees, and as long as the distributor is fitted correctly, there isn't any need to play with this. I'm just saying this so people don't rush out trying all different static advance settings. I, however, need to try advancing the initial advance beyond the 10 degrees to see if it improves the progression stage on my new carburettors. Most books recommend this as a part of the tuning procedure. Turning iniital advance may also require reducing the max advance on the distributor to avoid pinking, so it has to be done carefully.
These carbs are much more sensitive to ignition advance than the single progressive Solex or Webers. As anyone reading my blog on the conversion project will have realised by now, I have asked for trouble by fitting them - but that's the way I want it