by Esteban » Mon Jan 22, 2018 9:17 pm
Peter, most probably the springs are a set, just like in your first picture. However, in one Parts Manual, they are the same in the drawing and were sold as a set.
I was reviewing some pictures I took 8 years ago when I change the vacuum advance and serviced the rotating plate that holds in place the points. The plate rotates with the vacuum advance, and the cam of the distributor changes its angle with the centrifugal advance (governor springs). Of all the pictures that I have of the dismantle, according to Murphy's Law, I'm didn't take any pictures of the centrifugal advance. Sorry.
The centrifugal advance is key and very important. Some European cars of the 70s only had that system and not the vacuum. In your case, if one the springs have been changed, you might be getting more advance at high rpms, or sooner. You can check if the advance is correct with a little bit of patience, if you have a tachometer and a timing light. According to the manual, you should get 8 degrees more of advance at 1045 rpm than at 400 rpm (you probably have to disconnect the vacuum advance for the test) So if you have 10 degrees at 400 rpm, you should get 18 degrees at 1045 rpms.
Very few of us here in the States are running that distributor with the exception of those who had installed an aftermarket distributor instead of the waterprotect original one. For that reason, it will be difficult to get an answer for your question. Hope some of the Aussie members can chime in.
Owner of the same Patrol since 1967