Are new weights available for purchase?  Are they included in dist. rebuild kits?

Both distributors had one relatively thin spring on one weight and a thicker spring on the other.  Each of the thicker springs were very sloppy, applying no tension to their weight in the collapsed position.  It doesnt seem right?

I discovered the problem by manually advancing the weight mechanism and releasing.  There was a jerky return to position, accompanied by an an audible "ting" from one of the springs, which was hanging up on a bur on the weight post it was attached to.  With good glasses the cause was clear. 

I have also seen the worn posts that engage these slots - but don't have a good way to fix them. I do like the bronze bushed weights and generally heavier duty parts of the early version - and have built that style to use in my outfit. Good luck on the rebuild '46 - it may take a stack of donor parts to get a really good finished version.

I asked him about the springs.  He said the big heavier spring was a bad idea that Ford came up with.  Allowed for very rapid advance due to no tension on the weight, and then limited max. advance to somewhere above 3000 rpm. 

With regards to the short light spring and the heavy longer spring this might not have been such a bad idea.  As your guy said it gave a rapid advance up 'til the heavy spring started to extend then a more gradual advance. The problem is that it is very hard to develop a curve like that without a lot of dyno time for each carb & cam combo so yeh for most tuners not a great help.

Yes there was a lot of wear in the slots and on the pins.  That was what initially worried me.  The wear on one pin was .015, and the slot it fit in had a wear of .012, if memory serves.  The pins new are .250.  "Has anyone disassembled one of these...?"  Good question.  My feeling is that the same wear issues would be found in an Autozone "rebuilt" dist. 

I have to say that diving into the mysteries of the distributor has been fun.  Having read quite a few distributor posts in the past, I still lacked a lot of understanding regarding what they were talking about. 

The wear of the pin and slots would not cause any problems with dwell.  I would say your distributor has a worn cam.  I'll bet when you set the points with a feeler gauge, the dwell is too short.  That's because the tips of the cam lobes are worn or polished off.

John in Selma, IN

John,

If the dist. cam is worn as you suggest, what would be the best way to set points and dwell?  Optimum gap or dwell, or compromise?

You asked a loaded question.  The "best way" would be to replace the cam.  However, I don't practice what I preach, on my Ranchero it seems to run better when I set the dwell.  Pattern on the 'scope looks better that way too.

John

        If you can find a better/newer cam...... use it. The points have to open some amount to decrease "sparking" so the coil can charge, the amount of time (dwell) affects the amount of charge also. Which all means the spark will get weaker and you'll lose top end power first. As John said!

Yes the dist. came from me.  I think about the Pertronix everynow and then, but also remember I have purchased three of them and they all were toast within 2500 total accumulated miles.  One failure was due entirely to me leaving the ignition on.  Never found the cause of the other two.  The dist. that I was using had some kind of problem in that a regular type rotor was very difficult to fully seat on the shaft.  Actually didnt realize that problem until two caps and rotors were eaten up. 

One of the Pertronix burnouts happened on the road away from home, almost exactly two years ago, with the wife on board.  That day it was over 100, and not fun changing out the ignition to points.  So it has been points ever since.

Mike

If you braze up the end of the slot you can change the total centrifugal advance by gently using a rat tail file and a caliper. The two upper rotors I came up with both had slots for 15° advance (30° crank) so I shortened the travel so I could use more initial in the curve.

The Ford external ignition box simplifies trouble shooting - just plug in another box. They are cheap and pretty reliable if you take it easy on the amperage they have to switch.

Mike

        I built a Pertonix setup along the lines of what Steve is describing to you. Sent it to Mummert to use when we Dyno'd the engine. He took the Pertronix out, stuck Duraspark parts in it and we hooked it to an MSD6al. I have never touched since except to replace the cap and rotor and wires. It has worked flawlessly for three/ four years now. My F code makes cylinder pressure and will pull well over 6 grand  If there was a problem I'd have found I'd have seen it by now. This is the answer with today's technology.