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69 351 distributor

New User
Posts: 1
Joined: 01/13
Posted: 01/14/13 09:33 PM

Just started restoring my 69 sportsroof after being out of service for 13 years. When I tried to remove the rotor, I discovered that the distributor shaft turns freely if the rotor is turned. I pulled the distributor and the shaft turns as a unit and it doesn't appear that the pin on the lower gear is broken or sheared. Any suggestions? I know this isn't a good sign and think an engine tear down might be in the works...  

Post Reply
Posts: 455
Joined: 04/12
Posted: 01/15/13 07:57 AM

there are 2 places for a ford point type distributer to shear... allowing what you seem to have...

#1... the ROLL PIN... thru the gear..    

this has fooled me... a few times .. i got in and changed the timing chain.. as the distributer did not rotate... but what it was... is the OIL pump had SEIZED... it was on a 71 351C 2V ..  it had sheared the roll pin and locked the shaft in place.. so the distributer did not rotate when the engine was cranked.. but the engine still had proper compression ... and did not have that fast free wheeling cranking sound...

#2   and this is probably your issue...

the shaft where the rotor slips on is NOT a SOLID PART all the way to the gear...  the mechanical advance plate is there...   the shaft with the notch for rotor alignment goes in and is welded to a flat plate that fits on top of the mechanical advance weights..  .

grab the shaft and the gear...    if the rotor and the upper shaft still turns free... the upper shaft has broken free of the advance plate that was welded to the bottom...

don't throw the distributer away....    push the wire to the coil - backward through the hole in the side of the distributer..   you don't have to remove the points condenser or even loosen the nut..

spray a TINY amount of wd40 on the bottom of the vacuum advance screws...  not enough to get into the vacuum advance...    

turn the distributer back over and remove the tiny C clip from the end of the vacuum advance arm...  i usually place a magnet on the breaker plate to catch it..

take the vacuum advance screws out now they have had time to soak...   warning.. be careful they can break off.. ruining your day and your distributer...

if the advance screws come out completely .. slide the advance out..  take out the 2 screws that hold the breaker plate to the distributer housing.. and lift it out...

now you can see if the shaft is broken free of the plate across the advance weights...
please note that one end of that plate is different than the other.  note the numbers stamped in if visible from the top side.. note which end the limit pin is in..

if it is..   pull the felt plug...   then with a narrow pair of needle nose pliers.. reach into the end and grab the end of the wire retaining clip... if you are careful.. you can free it without bending the heck out of it..    the upper shaft can now be pulled carefully off the main shaft..

don't pull the weights off the lower shaft.. i have not personally found a source for the plastic bushings for them...

what to do now....    find another distributer... with the same numbers on the plate so you can swap this in...

or.... visit the junk yards... find a duraspark distributer... pry the reluctor off with 2 screwdrivers..

remove the vacuum advance clip and screws...  then the advance..

remove the 2 screws holding the breaker plate down... and remove the plate...

look inside... does the advance plate have similar numbers to yours???  if so... use those same needle nose pliers... pull the wire ring..  pull the upper shaft out and take it.. the breaker plate with the pick up coil on it..  the vacuum advance and the reluctor and tiny pin.. with you..

you have 2 options..    you can install the electronic ignition upper shaft and the breaker plate..

cut the round hole into a slot so you can install the 3 wire pick up coil harness..

you now have an electronic ignition distributer ... so you can use a blue duraspark module.. or even get creative and use a 4 pin delco hei module...

oh.. and it does not matter if the donar distributer has a big cap on an adaptor.. its the same parts...  yes.. if you take the adaptor and the cap with you and there is room.. you can install 8, 9 or 10MM wires..

you will also want the wiring harness from the distributer to the 4 pin connector on the module and to the round or square coil...  i like the square coils better.. but its up to you...

there is more info... to complete the swap.. but you are half way there..

other option.. to just buy a reman distributer..  

all depends on what you intend..  

Post Reply
Posts: 342
Joined: 11/09
Posted: 01/15/13 01:03 PM

I had the same problem with a 79 Capri (mustang) with a 2.3L the stupid roll pin broke holding the gear, i even re timed the distributer a few times and would run for a few sec and die. finally drove the pin out and came out in 3 pieces, replaced it and drove the car for another 2 years, never figured out why it ever broke in the frist place, and never happened again  

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