Wednesday, April 15, 2009

Dizzy Reconditioning

The distributor needed tearing down to put the new oil seal in, so I figured it was a good time to just recondition the whole unit.  The pin holding the dog to the distributor shaft turned out to be a broken off tap.  It seems to be nice and tight, so it shouldn't be a problem.  The points seem to be in good shape as well.  The problem came when I noticed that the advance plate wasn't securely fastened to the shaft.  This could cause all kinds of inconsistent firing, so that had to be fixed.  It seemed to be simply pressed together without much mechanical resilence left in it.  The easiest thing to do was to get out the mig welder and put a few tack welds to hold it in place.  I seemed to get a good weld, and ground it all down nicely.  With that repaired, I noticed that the springs on the centrifugal weights were mismatched.  I checked the resistance of the springs and found them to be pretty much the same.  That was good, but the one spring was longer than the other.  That wasn't good.  There was enough slack to allow one spring to be floppy when the other was tight.  I bent the longer one so it was roughly the same length as the other one.  I suppose that will do for now.  Its not hard to tear it apart again if it gives me trouble later on.

I foolishly didn't notice that there was a center punch mark on the point cam, when I took it apart.  I couldn't find a diagram of the distributor on how it was supposed to be assembled.  I assumed that the center punch mark goes on the same side as the center punch mark on the end of the shaft (toward the engine).  That makes sense, but if it turns out I'm wrong, its an easy fix.

I repacked the top bearing, and put the new oil seal in.  The old oil seal was like all the other ones on the bike, completely petrified.  I noticed that there were some makeshift shim washers in the assembly, so I put them back in the way they came out, with a bit of grease on them.  It USED TO work, so it should work again.  It turns freely and the points are nearly the same opening on both cam lobes.  I set the gap and put it all back together.

Well, almost back together.  The one insulating top hat washer on the point spring was damaged.  I'll either repair it with some epoxy or find a suitable replacement.  All the TO-3 transistor top hat washers I had were all too small.  I'll have to poke around and see what else I can find.  Once again an easy fix later.

1 comment:

  1. Many thanks to Sid who told me that the springs are SUPPOSED to be different in the dizzy. I'll have to put it back the way it was.

    I gotta get a bedside book... at a reasonable price before I get too far into re-assembly.