My 83's ignition timing was off so i went out and tried to time the ignition... dizzy was so far out of whack... i had to take it out and re-align the tally marks and such w/ the timing mark on the pully... anyway... now ive got the leading inition dead on.. but the trailing inition is showing advancement WELL past the first mark which is, as you all know, past where its supposed to be.. probably a good amount of degrees..anyway, when i move the vacuum thingy it wont change the timing... i did a search but this didnt yield any help as to what i have to do. i know it isnt stray signals because they are obviously different as the two systems show different timings on the pulley.

 

The inside of the the dizzy probably has some rust on the components that move to advance the timing or have frozen up for some reason. I had one that did the same thing. take the cap, rotor, and metal cover inside off and move the diaphgram and see if anything inside moves with it. If it doesn't then you will have to do some cleaning up inside of it or get a new one.

 

If you grab the rod that comes out of the trailing diaphragm and try to move it in and out, youll see if the advance plate is stuck.

 

if you {carefully ! don't let it get away !!! } remove the circlip retaining the rod to the pin on the plate, and remove the two screws holding the diaphram assembly to the distributor, you can remove the diaphram assembly from the distributor.

if you suck on the hose stub on the diaphram assembly the rod should move.

the plate should move pretty freely if you push the pin in the direction the rod would move it.

it is Possible that the wires from the hall sender are somehow binding the motion of the plate.

 

There is no hall sender in an FB distributor. The magnetic pickups are actually inductors.

 

that would tend to explain why all my looking up information on hall effect senders has not resulted in anything that looks like what is in my distributer

 

ok i did some of the testing you guys said... turns out... when i move the diaphram it adjusts the LEADING ignition..!?!?!? i checked the routing of all the wires... i have NO idea how to go about this now... any ideas? thanks

 

I'm puzzled, there are two vaccume adjusters, yes ?

what does the OTHER adjuster do ?

 

the other im not sure... but i know you're supposed to adjust the leading ignition by turning the distributor... and the trailing by moving the rightmost vacuum adjuster.

 

RIght, turning the dizzy will actually advance/retard both ign systems. The trailing vac pot only does the trailing. Theres a bearing on the plate that allows both leading and trailing to advance independently on vacuum. The whole plate moves in unison for the centrifugal advance.

 

yes i know that.. but what im saying is... instead of the trailing ignition being adjusted when i move the vacuum unit.. the leading does... and the trailing stays the same?!?! what could be going on?

 

Try moving the other vac adv unit, and see what it adjusts.

Brian

 

Nope.

 

Sorry, ok Im busted, It moves the reluctor.

 

Stupid question. Any chance you have the coil wires reversed going into the distributor cap? Or, leading and trailing plug wires reversed?